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Previous research has studied the effects of Cucurbita pepo extract on aquatic growth and health parameters. The present study aims to investigate the effects of C. pepo extracts on some blood factors and growth indices of rainbow trout, as well as the resistance of fish to Yersinia ruckeri. A total of 750 rainbow trout, with an average weight of 40-120 g, were randomly selected. The daily amount of feed required was calculated as a function of fish weight and water temperature. The indices of white blood cell (WBC), red blood cell (RBC), and lymphocyte counts were calculated. SPSS version 26 was used for statistical analysis. The results indicated that there was a significant difference between the experimental and control groups in the case of SGR, FCR, and SR, as well as, in hematological parameters, including WBC and RBC, but there was no significant difference between the two groups in the number of rainbow trout lymphocytes (P>0.05). C. pepo extract was effective on rainbow trout IgM and lysozyme levels, and there was a significant difference between the two groups (P<0.05). C. pepo extract was effective on the bactericidal rate of rainbow trout and there was a significant difference between the two groups (P<0.05). The results of this study provide a new perspective on the use of pumpkin seed (C. pepo) extract as a medicinal plant to improve hematological parameters, growth markers and immune response of rainbow trout (Oncorhynchus mykiss)., Resumen Investigaciones anteriores han estudiado los efectos del extracto de Cucurbita pepo sobre el crecimiento acuático y los parámetros sanitarios. El presente estudio pretende investigar los efectos de los extractos de C. pepo sobre algunos factores sanguíneos e índices de crecimiento de la trucha arco iris, así como la resistencia de los peces a Yersinia ruckeri. Se seleccionaron al azar 750 truchas arco iris, con un peso medio de 40-120 g. Se calculó la cantidad diaria de alimento necesaria en función del peso de los peces y de la temperatura del agua. Se calcularon los índices de recuento de glóbulos blancos (RGB), glóbulos rojos (RGR) y linfocitos. Para el análisis estadístico se utilizó el programa SPSS versión 26. Los resultados indicaron que había una diferencia significativa entre los grupos experimental y de control en el caso de tasa de crecimiento específica, índice de conversión, y tasa de supervivencia, así como, en los parámetros hematológicos, incluyendo RGB y RGR, pero no hubo diferencia significativa entre los dos grupos en el número de linfocitos de trucha arco iris (P>0.05). El extracto de C. pepo fue eficaz sobre los niveles de IgM y lisozima de la trucha arco iris, y hubo una diferencia significativa entre los dos grupos (P<0.05). El extracto de C. pepo fue eficaz sobre la tasa bactericida de la trucha arco iris y hubo una diferencia significativa entre los dos grupos (P<0.05). Los resultados de este estudio proporcionan una nueva perspectiva sobre el uso del extracto de semilla de calabaza (C. pepo) como planta medicinal para mejorar los parámetros hematológicos, los marcadores de crecimiento y la respuesta inmune de la trucha arco iris (Oncorhynchus mykiss).

Eichhornia crassipes es una planta acuática presente en cuerpos de agua con exceso de nutrientes, lo cual favorece su crecimiento y ocasiona un impacto negativo ambiental y social, situación que promueve la búsqueda de alternativas para su aprovechamiento. El objetivo fue evaluar propiedades físicas y químicas de E. crassipes como sustrato para germinación en hortalizas y en forma de bocashi para desarrollo de rábano. Como sustrato germinativo E. crassipes seco y molido se mezcló en cuatro proporciones diferentes con composta y agrolita, considerando un tratamiento control de 100 % de E. crassipes. Bajo un diseño completo al azar se germinaron semillas de Solanum lycopersicum, Cucurbita pepo y Cucumis sativus. En otro ensayo se realizó un bochashi con E. crassipes fresco el cual se aplicó en dosis de 0 %, 15 %, 30 % y 45 % en Raphanus sativus. La germinación varió en los tratamientos con E. crassipes de 0-99 %. Cantidades de 25 % y 50 % de E. crassipes mostraron las mejores características físicas y químicas como sustratos. El bocashi elaborado con E. crassipes mostró ventajas en la calidad de bulbo de rábano indicando dosis de 15 % como recomendable para su producción.

[Resumen] El aumento de la población mundial, y, por tanto, el incremento en la demanda de alimentos obtenidos mediante el monocultivo fomentan la aparición de epidemias de enfermedades fúngicas que provocan pérdidas importantes en los cultivos. Esto, y la aparición de cepas de ciertos patógenos resistentes a los pesticidas clásicos, hace necesario un continuo desarrollo de nuevos productos fitosanitarios. Debido a las interesantes actividades biológicas que presentan las tiosemicarbazonas y sus complejos metálicos, en el presente Trabajo de Fin de Grado se ha estudiado la potencial actividad fitosanitaria de algunos compuestos de estos grupos. Por un lado, se ha medido la capacidad de algunas tiosemicarbazonas y sus complejos de zinc(II) para inhibir el crecimiento de los patógenos Botrytis cinerea y Phytophthora capsici. Por otro lado, se ha determinado la capacidad fitosanitaria in planta de esos compuestos usando Cucurbita pepo como huésped de los patógenos anteriores. Estos experimentos mostraron diferencias en la inhibición del crecimiento en función de los compuestos ensayados y del patógeno utilizado. De hecho, los resultados de un complejo en concreto mostraron evidencias de resistencia inducida en planta., [Resumo] O aumento da poboación mundial, e, polo tanto, o incremento na demanda de alimentos obtidos mediante o monocultivo fomentan a aparición de epidemias de enfermidades fúnxicas que provocan perdas importantes nos cultivos. Isto, e a aparición de cepas de certos patóxenos resistentes aos pesticidas clásicos, fai necesario un continuo desenvolvemento de novos produtos fitosanitarios. Debido ás interesantes actividades biolóxicas que presentan as tiosemicarbazonas e os seus complexos metálicos, no presente Traballo de Fin de Grao estudouse a potencial actividade fitosanitaria dalgúns compostos destes grupos. En primeiro lugar, mediuse a capacidade dalgunhas tiosemicarbazonas e os seus complexos de zinc(II) para inhibir o crecemento dos patóxenos Botrytis cinerea e Phytophthora capsici. En segundo lugar, determinouse a capacidade fitosanitaria in planta deses compostos usando Cucurbita pepo como hóspede dos patóxenos anteriores. Estes experimentos mostraron diferenzas na inhibición do crecemento dependendo dos compostos ensaiados e do patóxeno utilizado. De feito, os resultados dun complexo en concreto mostraron evidencias de resistencia inducida na planta., [Abstract] The increase in world population and, therefore, the rise in the demand for food obtained through monoculture triggers the appearance of epidemics of fungal diseases that cause significant crop losses. This fact, and the appearance of pathogens strains resistant to classic pesticides, makes necessary to continuously develop new phytosanitary products. Due to the interesting biological activities of thiosemicarbazones and their metal complexes, in this Final Degree Project we have studied the potential phytosanitary activity of some compounds of these groups. On one hand, the capacity of some thioemicarbazones and their zinc(II) complexes for inhibiting the growth of the pathogens Botrytis cinerea and Phytophthora capsici has been measured. On the other side, the in planta phytosanitary capacity of these compounds has been determined using Cucurbita pepo as a host for the pathogens mentioned above. These experiments showed differences in growth inhibition depending on the compounds tested and the pathogen used. In fact, the results for one particular complex showed signs of induced resistance in the plant.

In this paper we show that metabolic engineering in Cucurbita pepo hairy roots can be used to both effectively increase and modify cucurbitacins. Cucurbitacins are highly-oxygenated triterpenoids originally described in the Cucurbitaceae family, but have since been found in 15 taxonomically distant plant families. Cucurbitacin B, D, E and I are the most widespread amongst the Cucurbitaceae and they have both important biological and pharmacological activities. In this study C. pepo hairy roots were used as a platform to boost production and alter the structures of the afore mentioned cucurbitacins by metabolic engineering to potentially provide new or more desirable bioactivities. We report that the ability to induce cucurbitacin biosynthesis by basic Helix-Loop-Helix transcription factors is partially conserved within the Cucurbitaceae and therefore can potentially be used as a biotechnological tool to increase cucurbitacins in several genera of this family. Additionally, overexpression of a novel acyltransferase from cucurbitacin producing Iberis amara generates a hitherto undescribed acetylation at the C3-hydroxyl group of the cucurbitadienol backbone. While overexpression of the cytochromes P450 CsCYP88L2 and McCYP88L7 from Cucumis sativus and Momordica charantia (respectively), results in accumulation of new spectral feature as revealed by High resolution liquid chromatography mass spectroscopy analysis; the m/z of the new peak supports it might be a cucurbitacin hydroxylated at the C19 position in C. pepo hairy roots. Finally, this paper is a case study of how hairy roots can be used to metabolically engineer and introduce novel modifications in metabolic pathways that have not been fully elucidated.

In this paper we show that metabolic engineering in Cucurbita pepo hairy roots can be used to both effectively increase and modify cucurbitacins. Cucurbitacins are highly-oxygenated triterpenoids originally described in the Cucurbitaceae family, but have since been found in 15 taxonomically distant plant families. Cucurbitacin B, D, E and I are the most widespread amongst the Cucurbitaceae and they have both important biological and pharmacological activities. In this study C. pepo hairy roots were used as a platform to boost production and alter the structures of the afore mentioned cucurbitacins by metabolic engineering to potentially provide new or more desirable bioactivities. We report that the ability to induce cucurbitacin biosynthesis by basic Helix-Loop-Helix transcription factors is partially conserved within the Cucurbitaceae and therefore can potentially be used as a biotechnological tool to increase cucurbitacins in several genera of this family. Additionally, overexpression of a novel acyltransferase from cucurbitacin producing Iberis amara generates a hitherto undescribed acetylation at the C3-hydroxyl group of the cucurbitadienol backbone. While overexpression of the cytochromes P450 CsCYP88L2 and McCYP88L7 from Cucumis sativus and Momordica charantia (respectively), results in accumulation of new spectral feature as revealed by High resolution liquid chromatography mass spectroscopy analysis; the m/z of the new peak supports it might be a cucurbitacin hydroxylated at the C19 position in C. pepo hairy roots. Finally, this paper is a case study of how hairy roots can be used to metabolically engineer and introduce novel modifications in metabolic pathways that have not been fully elucidated.

Zucchini (Cucurbita pepo L.) is widely cultivated in temperate regions. One of the major production challenges is the damage caused by Aphis gossypii (Homoptera: Aphididae), a polyphagous aphid, which can negatively affect its host plant, both directly by feeding and indirectly by vectoring viruses. To gain insights into the transcriptome events that occur during the zucchini–aphid interaction and to understand the early-to-late defense response through gene expression profiles, we performed RNA-sequencing (RNA-Seq) on zucchini leaves challenged by A. gossypii (24, 48, and 96 h post-infestation; hpi). Data analysis indicated a complex and dynamic pattern of gene expression and a transient transcriptional reconfiguration that involved more than 700 differentially expressed genes (DEGs), including a large number of defense-related genes. The down-regulation of key genes of plant immunity, such as leucine-rich repeat (LRR) protein kinases, transcription factors, and genes associated with direct (i.e., protease inhibitors, cysteine peptidases, etc.) and indirect (i.e., terpene synthase) defense responses, suggests the aphid ability to manipulate plant immune responses. We also investigated the emission of volatile organic compounds (VOCs) from infested plants and observed a reduced emission of (E)-β-caryophyllene at 48 hpi, likely the result of aphid effectors, which reflects the down-regulation of two genes involved in the biosynthesis of terpenoids. We showed that (E)-β-caryophyllene emission was modified by the duration of plant infestation and by aphid density and that this molecule highly attracts Aphidius colemani, a parasitic wasp of A. gossypii. With our results we contributed to the identification of genes involved in cucurbit plant interactions with phloem feeders. Our findings may also help pave the way toward developing tolerant zucchini varieties and to identify molecules for sustainable management of harmful insect populations.

[EN] Background Summer squash (Cucurbita pepo: Cucurbitaceae) are a popular horticultural crop for which there is insufficient genomic and transcriptomic information. Gene expression atlases are crucial for the identification of genes expressed in different tissues at various plant developmental stages. Here, we present the first comprehensive gene expression atlas for a summer squash cultivar, including transcripts obtained from seeds, shoots, leaf stem, young and developed leaves, male and female flowers, fruits of seven developmental stages, as well as primary and lateral roots. Results In total, 27,868 genes and 2352 novel transcripts were annotated from these 16 tissues, with over 18,000 genes common to all tissue groups. Of these, 3812 were identified as housekeeping genes, half of which assigned to known gene ontologies. Flowers, seeds, and young fruits had the largest number of specific genes, whilst intermediate-age fruits the fewest. There also were genes that were differentially expressed in the various tissues, the male flower being the tissue with the most differentially expressed genes in pair-wise comparisons with the remaining tissues, and the leaf stem the least. The largest expression change during fruit development was early on, from female flower to fruit two days after pollination. A weighted correlation network analysis performed on the global gene expression dataset assigned 25,413 genes to 24 coexpression groups, and some of these groups exhibited strong tissue specificity. Conclusions These findings enrich our understanding about the transcriptomic events associated with summer squash development and ripening. This comprehensive gene expression atlas is expected not only to provide a global view of gene expression patterns in all major tissues in C. pepo but to also serve as a valuable resource for functional genomics and gene discovery in Cucurbitaceae.

[EN] Background Summer squash (Cucurbita pepo: Cucurbitaceae) are a popular horticultural crop for which there is insufficient genomic and transcriptomic information. Gene expression atlases are crucial for the identification of genes expressed in different tissues at various plant developmental stages. Here, we present the first comprehensive gene expression atlas for a summer squash cultivar, including transcripts obtained from seeds, shoots, leaf stem, young and developed leaves, male and female flowers, fruits of seven developmental stages, as well as primary and lateral roots. Results In total, 27,868 genes and 2352 novel transcripts were annotated from these 16 tissues, with over 18,000 genes common to all tissue groups. Of these, 3812 were identified as housekeeping genes, half of which assigned to known gene ontologies. Flowers, seeds, and young fruits had the largest number of specific genes, whilst intermediate-age fruits the fewest. There also were genes that were differentially expressed in the various tissues, the male flower being the tissue with the most differentially expressed genes in pair-wise comparisons with the remaining tissues, and the leaf stem the least. The largest expression change during fruit development was early on, from female flower to fruit two days after pollination. A weighted correlation network analysis performed on the global gene expression dataset assigned 25,413 genes to 24 coexpression groups, and some of these groups exhibited strong tissue specificity. Conclusions These findings enrich our understanding about the transcriptomic events associated with summer squash development and ripening. This comprehensive gene expression atlas is expected not only to provide a global view of gene expression patterns in all major tissues in C. pepo but to also serve as a valuable resource for functional genomics and gene discovery in Cucurbitaceae.

The reduction of chemical inputs due to fertilizer and pesticide applications is a target shared both by farmers and consumers in order to minimize the side effects for human and environmental health. Among the possible strategies, the use of biostimulants has become increasingly important as demonstrated by the fast growth of their global market and by the increased rate of registration of new products. In this work, we assessed the effects of five bacterial strains (Pseu-domonas fluorescens Pf4, P. putida S1Pf1, P. protegens Pf7, P. migulae 8R6, and Pseudomonas sp. 5Vm1K), which were chosen according to their previously reported plant growth promotion traits and their positive effects on fruit/seed nutrient contents, on a local onion cultivar and on zucchini. The possible variations induced by the inoculation with the bacterial strains on the onion nutritional components were also evaluated. Inoculation resulted in significant growth stimulation and improvement of the mineral concentration of the onion bulb, induced particularly by 5Vm1K and S1Pf1, and in different effects on the flowering of the zucchini plants according to the bacterial strain. The present study provides new information regarding the activity of the five plant growth-promoting bacteria (PGPB) strains on onion and zucchini, two plant species rarely considered by the scientific literature despite their economic relevance.

The reduction of chemical inputs due to fertilizer and pesticide applications is a target shared both by farmers and consumers in order to minimize the side effects for human and environmental health. Among the possible strategies, the use of biostimulants has become increasingly important as demonstrated by the fast growth of their global market and by the increased rate of registration of new products. In this work, we assessed the effects of five bacterial strains (Pseu-domonas fluorescens Pf4, P. putida S1Pf1, P. protegens Pf7, P. migulae 8R6, and Pseudomonas sp. 5Vm1K), which were chosen according to their previously reported plant growth promotion traits and their positive effects on fruit/seed nutrient contents, on a local onion cultivar and on zucchini. The possible variations induced by the inoculation with the bacterial strains on the onion nutritional components were also evaluated. Inoculation resulted in significant growth stimulation and improvement of the mineral concentration of the onion bulb, induced particularly by 5Vm1K and S1Pf1, and in different effects on the flowering of the zucchini plants according to the bacterial strain. The present study provides new information regarding the activity of the five plant growth-promoting bacteria (PGPB) strains on onion and zucchini, two plant species rarely considered by the scientific literature despite their economic relevance.

In the organic production system, the use of fungicides for the treatment of seeds is prohibited. On account of that, thermotherapy and propolis are alternative methods of control of pathogens in seeds allowed in this system. This study was conducted to evaluate the zucchini seeds’ germination and vigor when subjected to thermotherapy and treatment with propolis. In the treatment with moist thermotherapy, three temperatures (50, 55, and 60 ºC) were evaluated in separate experiments. Four times of immersion of the seeds (15, 30, 45, and 60 minutes, besides the control treatment - time 0) were tested for each temperature. In the dry thermotherapy treatment, four times (24, 48, 72, and 96 hours) were evaluated in which the seeds remained in the oven at a constant temperature of 70 ºC. In the treatment with propolis, six concentrations (0.0, 0.2, 0.4, 0.6, 0.8, and 1.0%) were studied, with subsequent washing or without washing of the seeds, totaling 12 treatments. The germination test was installed in the complete randomized design, with four repetitions, and germination and vigor (germination speed index) were evaluated. The dry thermotherapy did not affect the germination and vigor of seeds. The moist thermotherapy at 50ºC reduced germination; besides, the values are within germination patterns. At 55 oC, the treatment has to be for a lesser time, until 30 minutes, and it is not recommended the treatment at 60 oC. For propolis, the treatment resulted in a little reduction in germination in the highest contents, the values are within the germination patterns, En el sistema de producción orgánica está prohibido el uso de fungicidas para el tratamiento de semillas. En consecuencia, la termoterapia y el propóleos son métodos alternativos en el control de patógenos de semillas permitidas en este sistema. El objetivo de este estudio fue evaluar la germinación y el vigor de semillas de calabacín sometidas a termoterapia y concentraciones de propóleos. En el tratamiento con termoterapia húmeda se evaluaron tres temperaturas (50, 55 y 60 ºC) en experimentos separados. Para cada temperatura, se estudiaron cuatro tiempos de inmersión de las semillas (15, 30, 45 y 60 minutos, además del control sin tratamiento - tiempo 0). En el tratamiento con termoterapia seca se evaluaron 4 tiempos (24, 48, 72 y 96 horas) en que las semillas permanecieron en la estufa a 70 ºC con temperatura constante. En el tratamiento con propóleos se estudiaron seis concentraciones (0,0; 0,2; 0,4; 0,6; 0,8 y 1,0%), con posterior lavado o no lavado de las semillas, totalizando 12 tratamientos. El análisis de germinación se realizó en delineamiento completamente casualizado, con cuatro repeticiones, y se evaluó la germinación y el vigor (índice de velocidad de germinación). La termoterapia seca no afectó la germinación ni el vigor de las semillas. La termoterapia húmeda a 50 ºC redujo la germinación, a pesar de que los valores todavía están dentro de los padrones comerciales de germinación. Con 55 ºC el tratamiento tiene que ser por menor período de tiempo, hasta 30 minutos, y no se recomienda el tratamiento a 60 ºC. En cuanto al propóleos, altas concentraciones redujeron la germinación, a pesar de que los valores todavía están dentro de los padrones comerciales de germinación.

[EN] Background: Zucchini fruit set can be limited due to unfavourable environmental conditions in off-seasons crops that caused ineffective pollination/fertilization. Parthenocarpy, the natural or artificial fruit development without fertilization, has been recognized as an important trait to avoid this problem, and is related to auxin signalling. Nevertheless, differences found in transcriptome analysis during early fruit development of zucchini suggest that other complementary pathways could regulate fruit formation in parthenocarpic cultivars of this species. The development of next-generation sequencing technologies (NGS) as RNA-sequencing (RNA-seq) opens a new horizon for mapping and quantifying transcriptome to understand the molecular basis of pathways that could regulate parthenocarpy in this species. The aim of the current study was to analyze fruit transcriptome of two cultivars of zucchini, a non-parthenocarpic cultivar and a parthenocarpic cultivar, in an attempt to identify key genes involved in parthenocarpy. Results: RNA-seq analysis of six libraries (unpollinated, pollinated and auxin treated fruit in a non-parthenocarpic and parthenocarpic cultivar) was performed mapping to a new version of C. pepo transcriptome, with a mean of 92% success rate of mapping. In the non-parthenocarpic cultivar, 6479 and 2186 genes were differentially expressed (DEGs) in pollinated fruit and auxin treated fruit, respectively. In the parthenocarpic cultivar, 10,497 in pollinated fruit and 5718 in auxin treated fruit. A comparison between transcriptome of the unpollinated fruit for each cultivar has been performed determining that 6120 genes were differentially expressed. Annotation analysis of these DEGs revealed that cell cycle, regulation of transcription, carbohydrate metabolism and coordination between auxin, ethylene and gibberellin were enriched biological processes during pollinated and parthenocarpic fruit set. Conclusion: This analysis revealed the important ro

Vermicompost (VC) is used as a fertilizer to satisfy the nutritive demand of plants, without affecting yield and quality. The objective of this study was to evaluate the development of zucchini using different fertilization sources under greenhouse conditions. Six fertilization treatments were evaluated: a) four nutrient solutions (T1-T4); b) vermicompost:sand mixture (2:3, v:v) (T5); and c) T5 + Steiner’s nutrient solution (T6), under greenhouse conditions with seven replicates that were distributed under a completely randomized design. The variables length, diameter, soluble solids content, fruit number, fruit weight and per-plant yield were evaluated. Analysis of variance and Tukey’s test were performed on the data (p < 0.05). The T6 treatment generated the best response for the variables: length, diameter, fruit number and weight, and yield, with 13.89 and 5.54 cm, 14.43 fruits, 274.57 g and 3,987.7 g plant-1, respectively., El vermicompost (VC) se utiliza como abono para satisfacer la demanda nutritiva de las plantas, sin afectar el rendimiento y la calidad. El objetivo del estudio fue evaluar el desarrollo de la calabacita bajo diferentes fuentes de fertilización en invernadero. Se evaluaron seis tratamientos de fertilización: a) cuatro soluciones nutritivas (T1-T4); b) mezcla vermicompost:arena (2:3, v:v) (T5); y c) T5 + solución nutritiva de Steiner (T6), bajo invernadero con siete repeticiones que se distribuyeron bajo un diseño completamente al azar. Se evaluaron las variables longitud, diámetro, contenido de sólidos solubles, peso del fruto, número de frutos y rendimiento por planta. A los datos se les realizó análisis de varianza y comparación de medias de Tukey (p < 0.05). El tratamiento T6 generó la mejor respuesta para las variables: longitud, diámetro, número y peso de fruto, y rendimiento, con 13.89 y 5.54 cm, 14.43 frutos, 274.57 g y 3,987.7 g planta-1, respectivamente.

La calabacita se utiliza principalmente para consumo en fruto fresco; es rica en vitaminas y minerales. Para su producción se aplican cantidad elevadas de fertilizantes químicos (FQ) que aumentan los costos de producción y provocan daños ecológicos. En general, los FQ presentan baja eficiencia que podría aumentarse con el uso de productos como la zeolita. Por lo que, en Apatzingán Michoacán, se sembró en campo calabacita en diciembre de 2017, para determinar el efecto de la aplicación de zeolita (Z) como porcentaje de la dosis de FQ sobre la producción y rentabilidad económica. Se evaluaron los tratamientos: 100FQ, 25Z + 75FQ, 50Z + 50FQ, 75Z + 25FQ, 100Z, 0Z + 0FQ (los valores representan porcentajes). Se encontró que el tiempo a ocurrencia de las etapas fenológicas no se modificó por los tratamientos así, la emergencia ocurrió a los nueve días después de la siembra (dds), la floración a los 39 días, el primer corte de frutos a los 48 días y a los 71 días el último corte. El suministro de zeolita en mezclas con FQ no redujo la altura de la planta, diámetro del tallo y el número de hojas en comparación con la dosis completa de FQ. La mezcla que generó el mayor rendimiento de fruto fresco (37.8 t ha-1) y ganancia por peso invertido ($3.44) fue 25Z + 75FQ. Por lo que, en calabacita la aplicación de zeolita permite reducir la dosis de FQ con el consecuente incremento en rendimiento y rentabilidad económica., The zucchini is used mainly for consumption in fresh fruit; it is rich in vitamins and minerals. For its production, high amounts of chemical fertilizers (CF) are applied, which increase production costs and cause ecological damage. In general, CF present low efficiency that could be increased with the use of products such as zeolite. As far as Apatzingan Michoacán, it was planted in zucchini field in December of 2017, to determine the effect of the application of zeolite (Z) as a percentage of the CF dose on production and economic profitability. The treatments were evaluated: 100CF, 25Z + 75CF, 50Z + 50CF, 75Z + 25CF, 100Z, 0Z + 0CF (the values represent percentages). It was found that the time to occur of the phenological stages was not modified by the treatments, the emergence occurred nine days after sowing (dds), flowering at 39 days, the first cut of fruits at 48 days and at 71 days the last cut. The supply of zeolite in mixtures with CF did not reduce plant height, stem diameter and number of leaves compared to the full dose of CF. The mixture that generated the highest yield of fresh fruit (37.8 t ha-1) and gain per peso invested ($3.44) was 25Z + 75CF. So, in zucchini the application of zeolite allows to reduce the dose of CF with the consequent increase in yield and economic profitability.

Vermicompost (VC) is used as a fertilizer to satisfy the nutritive demand of plants, without affecting yield and quality. The objective of this study was to evaluate the development of zucchini using different fertilization sources under greenhouse conditions. Six fertilization treatments were evaluated: a) four nutrient solutions (T1-T4); b) vermicompost:sand mixture (2:3, v:v) (T5); and c) T5 + Steiner’s nutrient solution (T6), under greenhouse conditions with seven replicates that were distributed under a completely randomized design. The variables length, diameter, soluble solids content, fruit number, fruit weight and per-plant yield were evaluated. Analysis of variance and Tukey’s test were performed on the data (p < 0.05). The T6 treatment generated the best response for the variables: length, diameter, fruit number and weight, and yield, with 13.89 and 5.54 cm, 14.43 fruits, 274.57 g and 3,987.7 g plant-1, respectively., El vermicompost (VC) se utiliza como abono para satisfacer la demanda nutritiva de las plantas, sin afectar el rendimiento y la calidad. El objetivo del estudio fue evaluar el desarrollo de la calabacita bajo diferentes fuentes de fertilización en invernadero. Se evaluaron seis tratamientos de fertilización: a) cuatro soluciones nutritivas (T1-T4); b) mezcla vermicompost:arena (2:3, v:v) (T5); y c) T5 + solución nutritiva de Steiner (T6), bajo invernadero con siete repeticiones que se distribuyeron bajo un diseño completamente al azar. Se evaluaron las variables longitud, diámetro, contenido de sólidos solubles, peso del fruto, número de frutos y rendimiento por planta. A los datos se les realizó análisis de varianza y comparación de medias de Tukey (p < 0.05). El tratamiento T6 generó la mejor respuesta para las variables: longitud, diámetro, número y peso de fruto, y rendimiento, con 13.89 y 5.54 cm, 14.43 frutos, 274.57 g y 3,987.7 g planta-1, respectivamente.

La calabacita se utiliza principalmente para consumo en fruto fresco; es rica en vitaminas y minerales. Para su producción se aplican cantidad elevadas de fertilizantes químicos (FQ) que aumentan los costos de producción y provocan daños ecológicos. En general, los FQ presentan baja eficiencia que podría aumentarse con el uso de productos como la zeolita. Por lo que, en Apatzingán Michoacán, se sembró en campo calabacita en diciembre de 2017, para determinar el efecto de la aplicación de zeolita (Z) como porcentaje de la dosis de FQ sobre la producción y rentabilidad económica. Se evaluaron los tratamientos: 100FQ, 25Z + 75FQ, 50Z + 50FQ, 75Z + 25FQ, 100Z, 0Z + 0FQ (los valores representan porcentajes). Se encontró que el tiempo a ocurrencia de las etapas fenológicas no se modificó por los tratamientos así, la emergencia ocurrió a los nueve días después de la siembra (dds), la floración a los 39 días, el primer corte de frutos a los 48 días y a los 71 días el último corte. El suministro de zeolita en mezclas con FQ no redujo la altura de la planta, diámetro del tallo y el número de hojas en comparación con la dosis completa de FQ. La mezcla que generó el mayor rendimiento de fruto fresco (37.8 t ha-1) y ganancia por peso invertido ($3.44) fue 25Z + 75FQ. Por lo que, en calabacita la aplicación de zeolita permite reducir la dosis de FQ con el consecuente incremento en rendimiento y rentabilidad económica., The zucchini is used mainly for consumption in fresh fruit; it is rich in vitamins and minerals. For its production, high amounts of chemical fertilizers (CF) are applied, which increase production costs and cause ecological damage. In general, CF present low efficiency that could be increased with the use of products such as zeolite. As far as Apatzingan Michoacán, it was planted in zucchini field in December of 2017, to determine the effect of the application of zeolite (Z) as a percentage of the CF dose on production and economic profitability. The treatments were evaluated: 100CF, 25Z + 75CF, 50Z + 50CF, 75Z + 25CF, 100Z, 0Z + 0CF (the values represent percentages). It was found that the time to occur of the phenological stages was not modified by the treatments, the emergence occurred nine days after sowing (dds), flowering at 39 days, the first cut of fruits at 48 days and at 71 days the last cut. The supply of zeolite in mixtures with CF did not reduce plant height, stem diameter and number of leaves compared to the full dose of CF. The mixture that generated the highest yield of fresh fruit (37.8 t ha-1) and gain per peso invested ($3.44) was 25Z + 75CF. So, in zucchini the application of zeolite allows to reduce the dose of CF with the consequent increase in yield and economic profitability.

Differences between specialist and generalist pollinators provide insight into the evolution of specialization in plant-pollinator interactions. Plants of the genus Cucurbita (Cucurbitaceae) are visited by both generalist pollinators (e.g., Apis mellifera) and by specialist pollinators (e.g., Peponapis pruinosa). Previous studies have estimated pollinator effectiveness of Apis mellifera (honey bees), and Peponapis pruinosa (squash bees) in agricultural Cucurbita species, but none have investigated behavioral differences that underlie variation in effectiveness. In the summer of 2017, I conducted single visit pollinator effectiveness trials on 21 acorn squash (Cucurbita pepo) plants at the UC San Diego Biology Field Station in San Diego County, California to link interspecific behavioral differences of pollinators to their effectiveness. Female squash bees spent more than seven times longer per single visit in contact with squash stigmas and in turn deposited more than ten times more pollen compared to generalist honey bees. For all trials combined pollen deposition and fruit set increased with time bees spent on receptive stigmatic surfaces. Single visits by squash bees were more likely to result in fruit set compared to honey bees (85% vs. 12%). In terms of single visits, these results indicate that Apis mellifera are less effective at pollinating acorn squash compared to female Peponapis pruinosa. The results of this study differ from previous studies because Apis mellifera on our study site forages for pollen from a variety of different plant species in the surrounding landscape. In agricultural systems, in contrast, honey bees may have fewer options for pollen foraging.

Pumpkins are grown on 5,000 acres in Indiana with an average yield of 6.75 tons per acre. Successful pumpkin production requires the use of varieties that yield well and produce pumpkins of the size, shape, color, and quality demanded by the market. Genetic resistance to the fungal disease powdery mildew is present in some varieties. This trial was designed to evaluate performance of pumpkin varieties in northern Indiana with and without treatment for powdery mildew. The trial included fourteen orange jack-o-lantern size pumpkins, one small or 'pie' pumpkin and one specialty yellow pumpkin.

Differences between specialist and generalist pollinators provide insight into the evolution of specialization in plant-pollinator interactions. Plants of the genus Cucurbita (Cucurbitaceae) are visited by both generalist pollinators (e.g., Apis mellifera) and by specialist pollinators (e.g., Peponapis pruinosa). Previous studies have estimated pollinator effectiveness of Apis mellifera (honey bees), and Peponapis pruinosa (squash bees) in agricultural Cucurbita species, but none have investigated behavioral differences that underlie variation in effectiveness. In the summer of 2017, I conducted single visit pollinator effectiveness trials on 21 acorn squash (Cucurbita pepo) plants at the UC San Diego Biology Field Station in San Diego County, California to link interspecific behavioral differences of pollinators to their effectiveness. Female squash bees spent more than seven times longer per single visit in contact with squash stigmas and in turn deposited more than ten times more pollen compared to generalist honey bees. For all trials combined pollen deposition and fruit set increased with time bees spent on receptive stigmatic surfaces. Single visits by squash bees were more likely to result in fruit set compared to honey bees (85% vs. 12%). In terms of single visits, these results indicate that Apis mellifera are less effective at pollinating acorn squash compared to female Peponapis pruinosa. The results of this study differ from previous studies because Apis mellifera on our study site forages for pollen from a variety of different plant species in the surrounding landscape. In agricultural systems, in contrast, honey bees may have fewer options for pollen foraging.

Pumpkins are grown on 5,000 acres in Indiana with an average yield of 6.75 tons per acre. Successful pumpkin production requires the use of varieties that yield well and produce pumpkins of the size, shape, color, and quality demanded by the market. Genetic resistance to the fungal disease powdery mildew is present in some varieties. This trial was designed to evaluate performance of pumpkin varieties in northern Indiana with and without treatment for powdery mildew. The trial included fourteen orange jack-o-lantern size pumpkins, one small or 'pie' pumpkin and one specialty yellow pumpkin.

Проведено дослідження процесів вилучення ДДТ з сірого лісового ґрунту рослинами кабачків (Cucurbita pepo) та квасолі (Phaseolus vulgaris) на фоні різних норм мінерального живлення. Показано, що рослини кабачків доцільно використовувати у технологіях фіторемедіації забруднених хлорорганічними пестицидами ґрунтів., Проведены исследования процессов извлечения ДДТ из серой лесной почвы растениями кабачков (Cucurbita pepo) и фасоли (Phaseolus vulgaris) на фоне различных норм минеральных удобрений. Показано, что растения кабачков целесообразно использовать в технологиях фиторемедиации загрязненных хлорорганическими пестицидами почв., Researches of processes of extraction DDT by plants of vegetable marrows (Cucurbita pepo) and string beans (Phaseolus vulgaris) from grey wood soil on a background of various norms of mineral fertilizers are carried out. It is shown; that plants of vegetable marrows are expedient for using in technologies of phytoremediation of polluted with organochlorine pesticides soils.

Проведено дослідження процесів вилучення ДДТ з сірого лісового ґрунту рослинами кабачків (Cucurbita pepo) та квасолі (Phaseolus vulgaris) на фоні різних норм мінерального живлення. Показано, що рослини кабачків доцільно використовувати у технологіях фіторемедіації забруднених хлорорганічними пестицидами ґрунтів., Проведены исследования процессов извлечения ДДТ из серой лесной почвы растениями кабачков (Cucurbita pepo) и фасоли (Phaseolus vulgaris) на фоне различных норм минеральных удобрений. Показано, что растения кабачков целесообразно использовать в технологиях фиторемедиации загрязненных хлорорганическими пестицидами почв., Researches of processes of extraction DDT by plants of vegetable marrows (Cucurbita pepo) and string beans (Phaseolus vulgaris) from grey wood soil on a background of various norms of mineral fertilizers are carried out. It is shown; that plants of vegetable marrows are expedient for using in technologies of phytoremediation of polluted with organochlorine pesticides soils.

Проведено дослідження процесів вилучення ДДТ з сірого лісового ґрунту рослинами кабачків (Cucurbita pepo) та квасолі (Phaseolus vulgaris) на фоні різних норм мінерального живлення. Показано, що рослини кабачків доцільно використовувати у технологіях фіторемедіації забруднених хлорорганічними пестицидами ґрунтів., Проведены исследования процессов извлечения ДДТ из серой лесной почвы растениями кабачков (Cucurbita pepo) и фасоли (Phaseolus vulgaris) на фоне различных норм минеральных удобрений. Показано, что растения кабачков целесообразно использовать в технологиях фиторемедиации загрязненных хлорорганическими пестицидами почв., Researches of processes of extraction DDT by plants of vegetable marrows (Cucurbita pepo) and string beans (Phaseolus vulgaris) from grey wood soil on a background of various norms of mineral fertilizers are carried out. It is shown; that plants of vegetable marrows are expedient for using in technologies of phytoremediation of polluted with organochlorine pesticides soils.

The goal of this study was to increase the fresh-cut zucchini shelf-life with glutamic acid biofertilizer. Treatments consisted of foliar applications of aqueous solutions of the bacterial fermentation containing 30% L-glutamic acid, at 14th, 21st, 28th, and 35th days after transplanting, at 0.2 and 0.4 mL L-1, 100 mL per plant of 7 days, starting at 14 days after transplant during the whole cycle (42 days). Zucchini fruits were pre-selected, sanitized and minimally processed into strips. Fruits were weighed (100 g) and placed into plastic bags of low density polyethylene (70 um). After sealing bags were stored. Plastic bags were kept at 6 ± 1 °C and 95% relativity humidity. Weight loss, soluble solids content, pH, titratable acidity, and color were performed at regular intervals of two days during eight days. To increase the fresh-cut zucchini shelf-life it is recommended to apply 0.4 mL L-1 glutamic acid biofertilizer., El objetivo de este estudio fue evaluar el aumento de la vida útil del fruto de calabacín cortado fresco con el uso de ácido glutámico. Los tratamientos consistieron en aplicaciones foliares de soluciones acuosas de la fermentación bacteriana de ácido L-glutámico 30%, a los 14, 21, 28 y 35 días después del trasplante, en diferentes concentraciones (0,2 y 0,4 mL L-1), cada aplicación fue de 100 mL. La primera aplicación foliar fue después de 14 días de realizado el trasplante en campo. En un ciclo total de 42 días. Posteriormente fueron preseleccionados los frutos, desinfectados y mínimamente procesados en tiras. Se usaron 100 g de fruto, colocados en bolsas de plástico de polietileno de baja densidad (70 fim), selladas y almacenadas a 6 ± 1 °C con humedad relativa del 95%. Fue medido el peso, contenido de sólidos solubles, pH, acidez titulable y color, en intervalos regulares de dos días durante un total de ocho días. Se concluye que para aumentar la vida útil del calabacín recién cortado se recomienda aplicar 0,4 mL L-1 de ácido glutámico.

The goal of this study was to increase the fresh-cut zucchini shelf-life with glutamic acid biofertilizer. Treatments consisted of foliar applications of aqueous solutions of the bacterial fermentation containing 30% L-glutamic acid, at 14th, 21st, 28th, and 35th days after transplanting, at 0.2 and 0.4 mL L-1, 100 mL per plant of 7 days, starting at 14 days after transplant during the whole cycle (42 days). Zucchini fruits were pre-selected, sanitized and minimally processed into strips. Fruits were weighed (100 g) and placed into plastic bags of low density polyethylene (70 um). After sealing bags were stored. Plastic bags were kept at 6 ± 1 °C and 95% relativity humidity. Weight loss, soluble solids content, pH, titratable acidity, and color were performed at regular intervals of two days during eight days. To increase the fresh-cut zucchini shelf-life it is recommended to apply 0.4 mL L-1 glutamic acid biofertilizer., El objetivo de este estudio fue evaluar el aumento de la vida útil del fruto de calabacín cortado fresco con el uso de ácido glutámico. Los tratamientos consistieron en aplicaciones foliares de soluciones acuosas de la fermentación bacteriana de ácido L-glutámico 30%, a los 14, 21, 28 y 35 días después del trasplante, en diferentes concentraciones (0,2 y 0,4 mL L-1), cada aplicación fue de 100 mL. La primera aplicación foliar fue después de 14 días de realizado el trasplante en campo. En un ciclo total de 42 días. Posteriormente fueron preseleccionados los frutos, desinfectados y mínimamente procesados en tiras. Se usaron 100 g de fruto, colocados en bolsas de plástico de polietileno de baja densidad (70 fim), selladas y almacenadas a 6 ± 1 °C con humedad relativa del 95%. Fue medido el peso, contenido de sólidos solubles, pH, acidez titulable y color, en intervalos regulares de dos días durante un total de ocho días. Se concluye que para aumentar la vida útil del calabacín recién cortado se recomienda aplicar 0,4 mL L-1 de ácido glutámico.

[EN] Cucurbit crops are economically important worldwide. One of the most serious threats to cucurbit production is Zucchini yellow mosaic virus (ZYMV). Several resistant accessions were identified in Cucurbita moschata and their resistance was introgressed into Cucurbita pepo. However, the mode of inheritance of ZYMV resistance in C. pepo presents a great challenge to attempts at introgressing resistance into elite germplasm. The main goal of this work was to analyze the inheritance of ZYMV resistance and to identify markers associated with genes conferring resistance. An Illumina GoldenGate assay allowed us to assess polymorphism among nine squash genotypes and to discover six polymorphic single-nucleotide polymorphisms (SNPs) between two near-isogenic lines, "True French" (susceptible to ZYMV) and Accession 381e (resistant to ZYMV). Two F-2 and three BC1 populations obtained from crossing the ZYMV-resistant Accession 381e with two susceptible ones, the zucchini True French and the cocozelle "San Pasquale," were assayed for ZYMV resistance. Molecular analysis revealed an approximately 90% association between SNP1 and resistance, which was confirmed using High Resolution Melt (HRM) and a CAPS marker. Co-segregation up to 72% in populations segregating for resistance was observed for two other SNP markers that could be potentially linked to genes involved in resistance expression. A functional prediction of proteins involved in the resistance response was performed on genome scaffolds containing the three SNPs of interest. Indeed, 16 full-length pathogen recognition genes (PRGs) were identified around the three SNP markers. In particular, we discovered that two nucleotide-binding site leucine-rich repeat (NBS-LRR) protein-encoding genes were located near the SNP1 marker. The investigation of ZYMV resistance in squash populations and the genomic analysis performed in this work could be useful for better directing the introgression of disease resistance into elite C.

[EN] Background: Cucurbita pepo is a cucurbit with growing economic importance worldwide. Zucchini morphotype is the most important within this highly variable species. Recently, transcriptome and Simple Sequence Repeat (SSR)- and Single Nucleotide Polymorphism (SNP)-based medium density maps have been reported, however further genomic tools are needed for efficient molecular breeding in the species. Our objective is to combine currently available complete transcriptomes and the Zucchini genome sequence with high throughput genotyping methods, mapping population development and extensive phenotyping to facilitate the advance of genomic research in this species. Results: We report the Genotyping-by-sequencing analysis of a RIL population developed from the inter subspecific cross Zucchini x Scallop (ssp. pepo x ssp. ovifera). Several thousands of SNP markers were identified and genotyped, followed by the construction of a high-density linkage map based on 7,718 SNPs (average of 386 markers/linkage group) covering 2,817.6 cM of the whole genome, which is a great improvement with respect to previous maps. A QTL analysis was performed using phenotypic data obtained from the RIL population from three environments. In total, 48 consistent QTLs for vine, flowering and fruit quality traits were detected on the basis of a multiple-environment analysis, distributed in 33 independent positions in 15 LGs, and each QTL explained 1.5 62.9% of the phenotypic variance. Eight major QTLs, which could explain greater than 20% of the phenotypic variation were detected and the underlying candidate genes identified. Conclusions: Here we report the first SNP saturated map in the species, anchored to the physical map. Additionally, several consistent QTLs related to early flowering, fruit shape and length, and rind and flesh color are reported as well as candidate genes for them. This information will enhance molecular breeding in C. pepo and will assist the gene cloning underlying the stu

[EN] Cucurbit crops are economically important worldwide. One of the most serious threats to cucurbit production is Zucchini yellow mosaic virus (ZYMV). Several resistant accessions were identified in Cucurbita moschata and their resistance was introgressed into Cucurbita pepo. However, the mode of inheritance of ZYMV resistance in C. pepo presents a great challenge to attempts at introgressing resistance into elite germplasm. The main goal of this work was to analyze the inheritance of ZYMV resistance and to identify markers associated with genes conferring resistance. An Illumina GoldenGate assay allowed us to assess polymorphism among nine squash genotypes and to discover six polymorphic single-nucleotide polymorphisms (SNPs) between two near-isogenic lines, "True French" (susceptible to ZYMV) and Accession 381e (resistant to ZYMV). Two F-2 and three BC1 populations obtained from crossing the ZYMV-resistant Accession 381e with two susceptible ones, the zucchini True French and the cocozelle "San Pasquale," were assayed for ZYMV resistance. Molecular analysis revealed an approximately 90% association between SNP1 and resistance, which was confirmed using High Resolution Melt (HRM) and a CAPS marker. Co-segregation up to 72% in populations segregating for resistance was observed for two other SNP markers that could be potentially linked to genes involved in resistance expression. A functional prediction of proteins involved in the resistance response was performed on genome scaffolds containing the three SNPs of interest. Indeed, 16 full-length pathogen recognition genes (PRGs) were identified around the three SNP markers. In particular, we discovered that two nucleotide-binding site leucine-rich repeat (NBS-LRR) protein-encoding genes were located near the SNP1 marker. The investigation of ZYMV resistance in squash populations and the genomic analysis performed in this work could be useful for better directing the introgression of disease resistance into elite C.

[EN] Background: Cucurbita pepo is a cucurbit with growing economic importance worldwide. Zucchini morphotype is the most important within this highly variable species. Recently, transcriptome and Simple Sequence Repeat (SSR)- and Single Nucleotide Polymorphism (SNP)-based medium density maps have been reported, however further genomic tools are needed for efficient molecular breeding in the species. Our objective is to combine currently available complete transcriptomes and the Zucchini genome sequence with high throughput genotyping methods, mapping population development and extensive phenotyping to facilitate the advance of genomic research in this species. Results: We report the Genotyping-by-sequencing analysis of a RIL population developed from the inter subspecific cross Zucchini x Scallop (ssp. pepo x ssp. ovifera). Several thousands of SNP markers were identified and genotyped, followed by the construction of a high-density linkage map based on 7,718 SNPs (average of 386 markers/linkage group) covering 2,817.6 cM of the whole genome, which is a great improvement with respect to previous maps. A QTL analysis was performed using phenotypic data obtained from the RIL population from three environments. In total, 48 consistent QTLs for vine, flowering and fruit quality traits were detected on the basis of a multiple-environment analysis, distributed in 33 independent positions in 15 LGs, and each QTL explained 1.5 62.9% of the phenotypic variance. Eight major QTLs, which could explain greater than 20% of the phenotypic variation were detected and the underlying candidate genes identified. Conclusions: Here we report the first SNP saturated map in the species, anchored to the physical map. Additionally, several consistent QTLs related to early flowering, fruit shape and length, and rind and flesh color are reported as well as candidate genes for them. This information will enhance molecular breeding in C. pepo and will assist the gene cloning underlying the stu

[EN] Zucchini yellow mosaic virus (ZYMV) induces serious diseases in cucurbits. To create a tool to screen for resistance genes, we cloned a wild ZYMV isolate and inserted the visual marker Roseal to obtain recombinant clone ZYMV-Rosl. While in some plant-virus combinations Roseal induces accumulation of anthocyanins in infected tissues, ZYMV-Rosl infection of cucurbits did not lead to detectable anthocyanin accumulation. However, the recombinant virus did induce dark red pigmen-tation in infected tissues of the model plant Nicotiana ben-thamiana. In this species, ZYMV-Rosl multiplied efficiently in local inoculated tissue but only a few progeny particles estab-lished infection foci in upper leaves. We used this system to analyze the roles of Dicer-like (DCL) genes, core components of plant antiviral RNA silencing pathways, in ZYMV infection. ZYMV-Rosl local replication was not significantly affected in single DCL knockdown lines nor in double DCL2/4 and triple DCL2/3/4 knockdown lines. ZYMV-Rosl systemic accumula-tion was not affected in knockdown lines DCL1, DCL2, and DCL3. However in DCL4 and also in DCL2/4 and DCL2/3/4 knockdown lines, ZYMV-Rosl systemic accumulation dra-matically increased, which highlights the key role of DCL4 in restricting virus systemic movement. The effect of DCL4 on ZYMV systemic movement was confirmed with a wild-type version of the virus.

[EN] Zucchini yellow mosaic virus (ZYMV) induces serious diseases in cucurbits. To create a tool to screen for resistance genes, we cloned a wild ZYMV isolate and inserted the visual marker Roseal to obtain recombinant clone ZYMV-Rosl. While in some plant-virus combinations Roseal induces accumulation of anthocyanins in infected tissues, ZYMV-Rosl infection of cucurbits did not lead to detectable anthocyanin accumulation. However, the recombinant virus did induce dark red pigmen-tation in infected tissues of the model plant Nicotiana ben-thamiana. In this species, ZYMV-Rosl multiplied efficiently in local inoculated tissue but only a few progeny particles estab-lished infection foci in upper leaves. We used this system to analyze the roles of Dicer-like (DCL) genes, core components of plant antiviral RNA silencing pathways, in ZYMV infection. ZYMV-Rosl local replication was not significantly affected in single DCL knockdown lines nor in double DCL2/4 and triple DCL2/3/4 knockdown lines. ZYMV-Rosl systemic accumula-tion was not affected in knockdown lines DCL1, DCL2, and DCL3. However in DCL4 and also in DCL2/4 and DCL2/3/4 knockdown lines, ZYMV-Rosl systemic accumulation dra-matically increased, which highlights the key role of DCL4 in restricting virus systemic movement. The effect of DCL4 on ZYMV systemic movement was confirmed with a wild-type version of the virus.

The negative impact of conventional farming on environment and human health make improvements on farming management mandatory. Imaging techniques are implemented in remote sensing for monitoring crop fields and plant phenotyping programs. The increasingly large size and complexity of the data obtained by these techniques, makes the implementation of powerful mathematical tools necessary in order to identify informative parameters and to apply them in precision agriculture. Multicolor fluorescence imaging is a useful approach for the study of plant defense responses to stress factors at bench scale. However, it has not been fully applied to plant phenotyping. This work evaluates the possible application of multicolor fluorescence imaging in combination with thermography for the particular case of zucchini plants affected by soft-rot, caused by Dickeya dadantii. Several statistical models -based on logistic regression analysis (LRA) and artificial neural networks (ANN)- were obtained for the experimental system zucchini-D. dadantii, which classify new samples as “healthy” or “infected.” The LRA worked best in identifying high dose-infiltrated leaves (in infiltrated and non-infiltrated areas) whereas ANN offered a higher accuracy at identifying low dose-infiltrated areas. To assess the applicability of these results to cucurbits in a more general way, these models were validated for melon infected by the same pathogen, achieving accurate predictions for the infiltrated areas. The values of accuracy achieved are comparable to those found in the literature for classifiers identifying other infections based on data obtained by different techniques. Thus, MCFI in combination with thermography prove useful at providing data at lab scale that can be analyzed by machine learning. This approach could be scaled up to be applied in plant phenotyping.

A study was undertaken to investigate the economic feasibility of summer squash cultivation in tarai region of Uttarakhand during winter - spring season of 2013-14 and 2014-15. Among three transplanting dates, summer squash transplanted on 15th January was found to be best with respect to plant growth characters, total yield (373.50 q ha-1), net return (`2,46,542 ha-1) and benefit – cost ratio (2.72). Similarly, out of three low cost protected techniques evaluated along with control, low tunnel with black plastic mulch was observed as best with respect to plant growth characters, total yield (451.67 q ha-1). Whereas, the maximum net return (`2,87,628 ha-1) and benefit - cost ratio (3.58) was obtained in black plastic mulched plots. Out of 12 treatment combinations, summer squash planted on 15th January under black polyethylene mulch is most profitable in terms of getting maximum benefit - cost ratio of 4.41. Hence, the same is recommended for commercial cultivation of summer squash at farmer’s field under tarai condition of Uttarakhand.

[EN] The species Cucurbita pepo, which is the most important within the genus Cucurbita, is one of the least studied species of the Cucurbitaceae family. The development of genomic tools is fairly recent in this species. The use of a new generation of sequencing methods and mass genotyping has made progress in the investigation of gene mapping and development of new genetic maps in this species. A few years ago the first transcriptome was developed in the C. pepo species (Blanca et al., 2011), which allowed the in silico identification of molecular markers of high quality SNP type. Then, the first two SNP genetic maps were constructed by using massive sequencing technology 454/Roche and GoldenGate genotyping platform (Ilumina).The first map, with 304 SNPs mapped, was formed from an F2 population from the cross of two subspecies of C. pepo, the ovifera (texana) subspecies Scallop morphotype and pepo subspecies Zucchini morphotype, of great economic importance. The other genetic map was parallel constructed using an F2 population of crossing of two genetically very distant morphotypes, such as the pepo subspecies Pumpkin morphotype and ovifera (texana) subspecies Scallop morphotype (results not yet published). Both populations were phenotyped for many vegetative, flowering and fruit characters, and with SNP genotyping a study of QTLs was carried out (Quantitative Trait Loci) (Esteras et al., 2012). Since both populations were phenotyped for the same characters and were genotyped with the same set of markers it has been possible to compare the results obtained with both maps. This study aims to validate some of these QTLs, which were found to be of great commercial interest in the genetic map of the cross Pumpkin x Scallop, some of which are also common in the genetic map of the cross Scallop x Zucchini. This has been carried out by phenotyping and genotyping High Resolution Melting of four F3 families Pumpkin x Scallop selected, which started from mother plants with h, [ES] La especie Cucurbita pepo, que es la de mayor importancia dentro del género Cucurbita, es una de las especies menos estudiadas de la familia de las Cucurbitáceas. El desarrollo de herramientas genómicas es bastante reciente en esta especie. La utilización de una nueva generación de métodos de secuenciación y genotipado masivo ha permitido avanzar en la investigación de la cartografía de genes y elaboración de nuevos mapas genéticos en esta especie. Hace pocos años se desarrolló el primer transcriptoma en la especie de C. pepo (Blanca et al., 2011), lo cual permitió la identificación in silico de marcadores moleculares de alta calidad de tipo SNP. A continuación se construyeron los dos primeros mapas genéticos mediante SNPs, utilizando la tecnología de secuenciación masiva 454/Roche y la plataforma de genotipado GoldenGate (Ilumina). El primer mapa, con 304 SNPs mapeados, se realizó a partir de una población F2 del cruzamiento de dos subespecies de C. pepo, la subespecie ovifera (texana) morfotipo Scallop y la subespecie pepo morfotipo Zucchini, de gran importancia económica. El otro mapa genético se elaboró paralelamente a partir de una población F2 del cruzamiento de dos morfotipos muy alejados genéticamente, como son la subespecie pepo morfotipo Pumpkin y la subespecie ovifera (texana) morfotipo Scallop (resultados todavía no publicados). Ambas poblaciones se fenotiparon para numerosos caracteres vegetativos, de floración y de fruto, y junto con el genotipado de SNPs se llevó a cabo un estudio de QTLs (Quantitative Trait Loci) (Esteras et al., 2012). Como ambas poblaciones se fenotiparon para los mismos caracteres y se genotiparon con el mismo set de marcadores ha sido posible comparar los resultados obtenidos con ambos mapas. Este trabajo tiene como objetivo validar algunos de estos QTLs de gran interés comercial encontrados en el mapa genético del cruzamiento Pumpkin x Scallop, algunos de los cuales son comunes también en el mapa genético del cruzamiento Sc

[EN] The species Cucurbita pepo, which is the most important within the genus Cucurbita, is one of the least studied species of the Cucurbitaceae family. The development of genomic tools is fairly recent in this species. The use of a new generation of sequencing methods and mass genotyping has made progress in the investigation of gene mapping and development of new genetic maps in this species. A few years ago the first transcriptome was developed in the C. pepo species (Blanca et al., 2011), which allowed the in silico identification of molecular markers of high quality SNP type. Then, the first two SNP genetic maps were constructed by using massive sequencing technology 454/Roche and GoldenGate genotyping platform (Ilumina).The first map, with 304 SNPs mapped, was formed from an F2 population from the cross of two subspecies of C. pepo, the ovifera (texana) subspecies Scallop morphotype and pepo subspecies Zucchini morphotype, of great economic importance. The other genetic map was parallel constructed using an F2 population of crossing of two genetically very distant morphotypes, such as the pepo subspecies Pumpkin morphotype and ovifera (texana) subspecies Scallop morphotype (results not yet published). Both populations were phenotyped for many vegetative, flowering and fruit characters, and with SNP genotyping a study of QTLs was carried out (Quantitative Trait Loci) (Esteras et al., 2012). Since both populations were phenotyped for the same characters and were genotyped with the same set of markers it has been possible to compare the results obtained with both maps. This study aims to validate some of these QTLs, which were found to be of great commercial interest in the genetic map of the cross Pumpkin x Scallop, some of which are also common in the genetic map of the cross Scallop x Zucchini. This has been carried out by phenotyping and genotyping High Resolution Melting of four F3 families Pumpkin x Scallop selected, which started from mother plants with h, [ES] La especie Cucurbita pepo, que es la de mayor importancia dentro del género Cucurbita, es una de las especies menos estudiadas de la familia de las Cucurbitáceas. El desarrollo de herramientas genómicas es bastante reciente en esta especie. La utilización de una nueva generación de métodos de secuenciación y genotipado masivo ha permitido avanzar en la investigación de la cartografía de genes y elaboración de nuevos mapas genéticos en esta especie. Hace pocos años se desarrolló el primer transcriptoma en la especie de C. pepo (Blanca et al., 2011), lo cual permitió la identificación in silico de marcadores moleculares de alta calidad de tipo SNP. A continuación se construyeron los dos primeros mapas genéticos mediante SNPs, utilizando la tecnología de secuenciación masiva 454/Roche y la plataforma de genotipado GoldenGate (Ilumina). El primer mapa, con 304 SNPs mapeados, se realizó a partir de una población F2 del cruzamiento de dos subespecies de C. pepo, la subespecie ovifera (texana) morfotipo Scallop y la subespecie pepo morfotipo Zucchini, de gran importancia económica. El otro mapa genético se elaboró paralelamente a partir de una población F2 del cruzamiento de dos morfotipos muy alejados genéticamente, como son la subespecie pepo morfotipo Pumpkin y la subespecie ovifera (texana) morfotipo Scallop (resultados todavía no publicados). Ambas poblaciones se fenotiparon para numerosos caracteres vegetativos, de floración y de fruto, y junto con el genotipado de SNPs se llevó a cabo un estudio de QTLs (Quantitative Trait Loci) (Esteras et al., 2012). Como ambas poblaciones se fenotiparon para los mismos caracteres y se genotiparon con el mismo set de marcadores ha sido posible comparar los resultados obtenidos con ambos mapas. Este trabajo tiene como objetivo validar algunos de estos QTLs de gran interés comercial encontrados en el mapa genético del cruzamiento Pumpkin x Scallop, algunos de los cuales son comunes también en el mapa genético del cruzamiento Sc

[EN] The species Cucurbita pepo, which is the most important within the genus Cucurbita, is one of the least studied species of the Cucurbitaceae family. The development of genomic tools is fairly recent in this species. The use of a new generation of sequencing methods and mass genotyping has made progress in the investigation of gene mapping and development of new genetic maps in this species. A few years ago the first transcriptome was developed in the C. pepo species (Blanca et al., 2011), which allowed the in silico identification of molecular markers of high quality SNP type. Then, the first two SNP genetic maps were constructed by using massive sequencing technology 454/Roche and GoldenGate genotyping platform (Ilumina).The first map, with 304 SNPs mapped, was formed from an F2 population from the cross of two subspecies of C. pepo, the ovifera (texana) subspecies Scallop morphotype and pepo subspecies Zucchini morphotype, of great economic importance. The other genetic map was parallel constructed using an F2 population of crossing of two genetically very distant morphotypes, such as the pepo subspecies Pumpkin morphotype and ovifera (texana) subspecies Scallop morphotype (results not yet published). Both populations were phenotyped for many vegetative, flowering and fruit characters, and with SNP genotyping a study of QTLs was carried out (Quantitative Trait Loci) (Esteras et al., 2012). Since both populations were phenotyped for the same characters and were genotyped with the same set of markers it has been possible to compare the results obtained with both maps. This study aims to validate some of these QTLs, which were found to be of great commercial interest in the genetic map of the cross Pumpkin x Scallop, some of which are also common in the genetic map of the cross Scallop x Zucchini. This has been carried out by phenotyping and genotyping High Resolution Melting of four F3 families Pumpkin x Scallop selected, which started from mother plants with h, [ES] La especie Cucurbita pepo, que es la de mayor importancia dentro del género Cucurbita, es una de las especies menos estudiadas de la familia de las Cucurbitáceas. El desarrollo de herramientas genómicas es bastante reciente en esta especie. La utilización de una nueva generación de métodos de secuenciación y genotipado masivo ha permitido avanzar en la investigación de la cartografía de genes y elaboración de nuevos mapas genéticos en esta especie. Hace pocos años se desarrolló el primer transcriptoma en la especie de C. pepo (Blanca et al., 2011), lo cual permitió la identificación in silico de marcadores moleculares de alta calidad de tipo SNP. A continuación se construyeron los dos primeros mapas genéticos mediante SNPs, utilizando la tecnología de secuenciación masiva 454/Roche y la plataforma de genotipado GoldenGate (Ilumina). El primer mapa, con 304 SNPs mapeados, se realizó a partir de una población F2 del cruzamiento de dos subespecies de C. pepo, la subespecie ovifera (texana) morfotipo Scallop y la subespecie pepo morfotipo Zucchini, de gran importancia económica. El otro mapa genético se elaboró paralelamente a partir de una población F2 del cruzamiento de dos morfotipos muy alejados genéticamente, como son la subespecie pepo morfotipo Pumpkin y la subespecie ovifera (texana) morfotipo Scallop (resultados todavía no publicados). Ambas poblaciones se fenotiparon para numerosos caracteres vegetativos, de floración y de fruto, y junto con el genotipado de SNPs se llevó a cabo un estudio de QTLs (Quantitative Trait Loci) (Esteras et al., 2012). Como ambas poblaciones se fenotiparon para los mismos caracteres y se genotiparon con el mismo set de marcadores ha sido posible comparar los resultados obtenidos con ambos mapas. Este trabajo tiene como objetivo validar algunos de estos QTLs de gran interés comercial encontrados en el mapa genético del cruzamiento Pumpkin x Scallop, algunos de los cuales son comunes también en el mapa genético del cruzamiento Sc

The relationship between the initial (Pi) and final (Pf) population densities of Meloidogyne javanica in response to increasing initial inoculum levels and the effect on yield in zucchini cv. Amalthee (Cucurbita pepo L.) was determined using a geometric series of 12 Pi from 0 to 51,200 eggs/100 cm(3) of soil in pot experiments in a greenhouse. The maximum multiplication rate was 425, and the equilibrium density was 701,951 eggs/100 cm(3) soil. The relative yield, represented as dry top weight, fit the Seinhorst damage function model and the minimum relative yield (m) was 0.82 and the tolerance limit (T) was 402 J2/100 cm3 soil. Regression analyses indicated a negative relationship between the Pi and the leaf chlorophyll content (LCC) 40, 50, 60, and 70 days post-inoculation. The Pi and LCC fit the Seinhorst damage-function model. Zucchini cv. Dyamant was planted in a plastic greenhouse with a range of M. javanica Pi from 0 to 861 J2/100 cm3 soil. The maximum multiplication rate of M. javanica under field conditions was 3093, and the equilibrium density was 1485 J2/100 cm(3) soil. The relationship between Pi and relative yield, represented as fruit weight, fit the Seinhorst damage function model (P <0.0001, R-2 = 0.78); m was 0.48, and T was 0.02 J2/100 cm(3) soil. (C) 2014 Elsevier Ltd. All rights reserved., Postprint (published version)

Parthenocarpy is becoming an essential trait for off-season greenhouse production of Zucchini squash. Given that winter conditions promote a reduction in the number of male flowers and in the activity of pollinators, the application of synthetic auxins is currently the most widespread method to induce fruit set. We have evaluated the parthenocarpic tendency of 48 long-fruited accessions of Cucurbita pepo spp. pepo, from morphotypes Zucchini, Vegetable marrow and Cocozelle, including 45 traditional cultivars and 3 commercial hybrids, with the goal of identifying new sources of parthenocarpy for breeding programs. After the first screening, 20 selected accessions were evaluated for the growth rate of unpollinated fruit. Twelve of the selected accessions identified as either strongly parthenocarpic or non-parthenocarpic, were compared for fruit rate growth, ethylene production and ethylene sensitivity. Apart from the three control hybrids, the fastest parthenocarpic fruit growth was observed in 'CpCAL112', 'CM-37', 'E-27', 'PI261610', and 'V-185'. The source of the parthenocarpy of some of these accessions differs from that of the hybrids as it was not associated with the conversion of female into bisexual flowers or with the so-called "fruits with attached flowers" syndrome, which is an undesirable trait in current parthenocarpic hybrids. The alternative sources of parthenocarpy may be of great importance in current Zucchini breeding programs. We also demonstrate that the parthenocarpy of these accessions is associated with downregulation of ethylene production in unpollinated fruits during the first days post anthesis (DPA). In non-parthenocarpic accessions, unpollinated fruits boosted ethylene production at 3 DPA, concomitantly with fruit abortion and senescence, while in parthenocarpic accessions, fruits produced little ethylene at 3 DPA. Therefore, ethylene production in ovaries/fruits at 3 DPA can be used as a marker to identify and select parthenocarpy in Zucchi

Parthenocarpy is becoming an essential trait for off-season greenhouse production of Zucchini squash. Given that winter conditions promote a reduction in the number of male flowers and in the activity of pollinators, the application of synthetic auxins is currently the most widespread method to induce fruit set. We have evaluated the parthenocarpic tendency of 48 long-fruited accessions of Cucurbita pepo spp. pepo, from morphotypes Zucchini, Vegetable marrow and Cocozelle, including 45 traditional cultivars and 3 commercial hybrids, with the goal of identifying new sources of parthenocarpy for breeding programs. After the first screening, 20 selected accessions were evaluated for the growth rate of unpollinated fruit. Twelve of the selected accessions identified as either strongly parthenocarpic or non-parthenocarpic, were compared for fruit rate growth, ethylene production and ethylene sensitivity. Apart from the three control hybrids, the fastest parthenocarpic fruit growth was observed in 'CpCAL112', 'CM-37', 'E-27', 'PI261610', and 'V-185'. The source of the parthenocarpy of some of these accessions differs from that of the hybrids as it was not associated with the conversion of female into bisexual flowers or with the so-called "fruits with attached flowers" syndrome, which is an undesirable trait in current parthenocarpic hybrids. The alternative sources of parthenocarpy may be of great importance in current Zucchini breeding programs. We also demonstrate that the parthenocarpy of these accessions is associated with downregulation of ethylene production in unpollinated fruits during the first days post anthesis (DPA). In non-parthenocarpic accessions, unpollinated fruits boosted ethylene production at 3 DPA, concomitantly with fruit abortion and senescence, while in parthenocarpic accessions, fruits produced little ethylene at 3 DPA. Therefore, ethylene production in ovaries/fruits at 3 DPA can be used as a marker to identify and select parthenocarpy in Zucchi

The present research was undertaken to evaluate the effects of soil temperature on the life cycle of root-knot nematodes (RKN) on zucchini-squash in growth chambers and to assess the relationship between Meloidogyne incognita soil population densities at planting (Pi), its multiplication rate, and crop losses of zucchini in field conditions. Thermal requirements for M. incognita and M. javanica were determined by cultivating zucchini plants in pots inoculated with 200 second stage juveniles (J2) of each Meloidogyne species at constant temperatures of 17, 21, 25, and 28 A degrees C. Number of days from nematode inoculation until appearance of egg laying females and until egg hatching were separately recorded. For life cycle completion, base temperatures (Tb) of 12 A(0)C and 10.8 A(0)C and accumulated degree-days above Tb (S) of 456 and 526, were estimated for M. incognita and M. javanica, respectively. The relationship between fruit weight and M. incognita Pi fits the Seinhorst damage function, but differed accordingly to the cropping season, spring or autumn. Tolerance limits for M. incognita on zucchini were 8.1 J2 per 250 cm(3) of soil in spring and 1.5 in autumn cropping cycles, and the minimum relative yields were 0.61 in spring and 0.69 in autumn. Zucchini-squash was a poorer host for M. incognita in spring than in autumn, since maximum multiplication rates (a) and equilibrium densities (E) were lower in spring (a = 16-96; E = 274-484) than in autumn (a = 270-2307; E = 787-1227)., Postprint (published version)

[EN] The genetic variability of a Cucurbit aphid-borne yellows virus (CABYV) (genus Polerovirus, family Luteoviridae) population was evaluated by determining the nucleotide sequences of two genomic regions of CABYV isolates collected in open-field melon and squash crops during three consecutive years in Murcia (southeastern Spain). A phylogenetic analysis showed the existence of two major clades. The sequences did not cluster according to host, year, or locality of collection, and nucleotide similarities among isolates were 97 to 100 and 94 to 97% within and between clades, respectively. The ratio of nonsynonymous to synonymous nucleotide substitutions reflected that all open reading frames have been under purifying selection. Estimates of the population's genetic diversity were of the same magnitude as those previously reported for other plant virus populations sampled at larger spatial and temporal scales, suggesting either the presence of CABYV in the surveyed area long before it was first described, multiple introductions, or a particularly rapid diversification. We also determined the full-length sequences of three isolates, identifying the occurrence and location of recombination events along the CABYV genome. Furthermore, our field surveys indicated that Aphis gossypii was the major vector species of CABYV and the most abundant aphid species colonizing melon fields in the Murcia (Spain) region. Our surveys also suggested the importance of the weed species Ecballium elaterium as an alternative host and potential virus reservoir.

Background: We have identified a kind of parthenocarpy in zucchini squash which is associated with an incomplete andromonoecy, i.e. a partial conversion of female into bisexual flowers. Given that andromonoecy in this and other cucurbit species is caused by a reduction of ethylene production in the female flower, the associated parthenocarpic development of the fruit suggested the involvement of ethylene in fruit set and early fruit development. Results: We have compared the production of ethylene as well as the expression of 13 ethylene biosynthesis and signalling genes in pollinated and unpollinated ovaries/fruits of two cultivars, one of which is parthenocarpic (Cavili), while the other is non-parthenocarpic (Tosca). In the latter, unpollinated ovaries show an induction of ethylene biosynthesis and ethylene signal transduction pathway genes three days after anthesis, which is concomitant with the initiation of fruit abortion and senescence. Fruit set and early fruit development in pollinated flowers of both cultivars and unpollinated flowers of Cavili is coupled with low ethylene biosynthesis and signalling, which would also explain the partial andromonoecy in the parthenocarpic genotype. The reduction of ethylene production in the ovary cosegregates with parthenocarpy and partial andromonoecy in the selfing progeny of Cavili. Moreover, the induction of ethylene in anthesis (by ethephon treatments) reduced the percentage of bisexual parthenocarpic flowers in Cavili, while the inhibition of ethylene biosynthesis or response (by AVG and STS treatments) induces not only andromonoecy but also the parthenocarpic development of the fruit in both cultivars. Conclusions: Results demonstrate that a reduction of ethylene production or signalling in the zucchini flower is able to induce fruit set and early fruit development, and therefore that ethylene is actively involved in fruit set and early fruit development. Auxin and TIBA treatments, inducing fruit set and early frui

Background: We have identified a kind of parthenocarpy in zucchini squash which is associated with an incomplete andromonoecy, i.e. a partial conversion of female into bisexual flowers. Given that andromonoecy in this and other cucurbit species is caused by a reduction of ethylene production in the female flower, the associated parthenocarpic development of the fruit suggested the involvement of ethylene in fruit set and early fruit development. Results: We have compared the production of ethylene as well as the expression of 13 ethylene biosynthesis and signalling genes in pollinated and unpollinated ovaries/fruits of two cultivars, one of which is parthenocarpic (Cavili), while the other is non-parthenocarpic (Tosca). In the latter, unpollinated ovaries show an induction of ethylene biosynthesis and ethylene signal transduction pathway genes three days after anthesis, which is concomitant with the initiation of fruit abortion and senescence. Fruit set and early fruit development in pollinated flowers of both cultivars and unpollinated flowers of Cavili is coupled with low ethylene biosynthesis and signalling, which would also explain the partial andromonoecy in the parthenocarpic genotype. The reduction of ethylene production in the ovary cosegregates with parthenocarpy and partial andromonoecy in the selfing progeny of Cavili. Moreover, the induction of ethylene in anthesis (by ethephon treatments) reduced the percentage of bisexual parthenocarpic flowers in Cavili, while the inhibition of ethylene biosynthesis or response (by AVG and STS treatments) induces not only andromonoecy but also the parthenocarpic development of the fruit in both cultivars. Conclusions: Results demonstrate that a reduction of ethylene production or signalling in the zucchini flower is able to induce fruit set and early fruit development, and therefore that ethylene is actively involved in fruit set and early fruit development. Auxin and TIBA treatments, inducing fruit set and early frui

[EN] The genetic variability of a Cucurbit aphid-borne yellows virus (CABYV) (genus Polerovirus, family Luteoviridae) population was evaluated by determining the nucleotide sequences of two genomic regions of CABYV isolates collected in open-field melon and squash crops during three consecutive years in Murcia (southeastern Spain). A phylogenetic analysis showed the existence of two major clades. The sequences did not cluster according to host, year, or locality of collection, and nucleotide similarities among isolates were 97 to 100 and 94 to 97% within and between clades, respectively. The ratio of nonsynonymous to synonymous nucleotide substitutions reflected that all open reading frames have been under purifying selection. Estimates of the population's genetic diversity were of the same magnitude as those previously reported for other plant virus populations sampled at larger spatial and temporal scales, suggesting either the presence of CABYV in the surveyed area long before it was first described, multiple introductions, or a particularly rapid diversification. We also determined the full-length sequences of three isolates, identifying the occurrence and location of recombination events along the CABYV genome. Furthermore, our field surveys indicated that Aphis gossypii was the major vector species of CABYV and the most abundant aphid species colonizing melon fields in the Murcia (Spain) region. Our surveys also suggested the importance of the weed species Ecballium elaterium as an alternative host and potential virus reservoir.

In most plant species, initiation of lateral root primordia occurs above the elongation zone. However, in cucurbits and some other species, lateral root primordia initiation and development takes place in the apical meristem of the parental root. Composite transgenic plants obtained by Agrobacterium rhizogenes-mediated transformation are known as a suitable model to study root development. The aim of the present study was to establish this transformation technique for squash. The auxin-responsive promoter DR5 was cloned into the binary vectors pKGW-RR-MGW and pMDC162-GFP. Incorporation of 5-ethynyl-2-deoxyuridine (EdU) was used to evaluate the presence of DNA-synthesizing cells in the hypocotyl of squash seedlings to find out whether they were suitable for infection. Two A. rhizogenes strains, R1000 and MSU440, were used. Roots containing the respective constructs were selected based on DsRED1 or green fluorescent protein (GFP) fluorescence, and DR5::Egfp-gusA or DR5::gusA insertion, respectively, was verified by PCR. Distribution of the response to auxin was visualized by GFP fluorescence or -glucuronidase (GUS) activity staining and confirmed by immunolocalization of GFP and GUS proteins, respectively. Based on the distribution of EdU-labelled cells, it was determined that 6-day-old squash seedlings were suited for inoculation by A. rhizogenes since their root pericycle and the adjacent layers contain enough proliferating cells. Agrobacterium rhizogenes R1000 proved to be the most virulent strain on squash seedlings. Squash roots containing the respective constructs did not exhibit the hairy root phenotype and were morphologically and structurally similar to wild-type roots. The auxin response pattern in the root apex of squash resembled that in arabidopsis roots. Composite squash plants obtained by A. rhizogenes-mediated transformation are a good tool for the investigation of root apical meristem development and root branching., AuthorCount:6

[EN] Cucurbita pepo is a worldwide cultivated vegetable of American origin. Most of the widely grown commercial types are known as summer squashes and belong to the elongated forms of C. pepo ssp. pepo (Cocozelle, Vegetable marrow and Zucchini groups). These forms were developed in Europe after the arrival of the first American landraces through a process of selection and fixation that led to a loss of genetic diversity. Part of the genetic variability of the first American cultigens remains intact in diverse landraces that are still cultivated for self-consumption and sale in local markets. Using the first collection of genomic and EST-derived microsatellites that has just become available for the species, we compared the natural variation present in a collection of Spanish landraces with that of a set of commercial varieties and hybrids, representing current summer squash market offerings. A total of 194 alleles allowed us to distinguish all the genotypes, even those that were closely related. In general, Cocozelle and Vegetable marrow, groups with considerably long histories, were more variable than the Zucchini group, of more recent origin. We found significant genetic diversity among landraces. The variation present among landraces belonging to the Zucchini group was larger than that of the commercial cultivars. Cluster, principal coordinate and population structure results suggested that the variation of the Spanish landraces has not been extensively used in breeding. Commercial summer squashes can therefore benefit from this underexploited variability, especially from certain landraces that already display favourable commercial traits.

[EN] Cucurbita pepo is a worldwide cultivated vegetable of American origin. Most of the widely grown commercial types are known as summer squashes and belong to the elongated forms of C. pepo ssp. pepo (Cocozelle, Vegetable marrow and Zucchini groups). These forms were developed in Europe after the arrival of the first American landraces through a process of selection and fixation that led to a loss of genetic diversity. Part of the genetic variability of the first American cultigens remains intact in diverse landraces that are still cultivated for self-consumption and sale in local markets. Using the first collection of genomic and EST-derived microsatellites that has just become available for the species, we compared the natural variation present in a collection of Spanish landraces with that of a set of commercial varieties and hybrids, representing current summer squash market offerings. A total of 194 alleles allowed us to distinguish all the genotypes, even those that were closely related. In general, Cocozelle and Vegetable marrow, groups with considerably long histories, were more variable than the Zucchini group, of more recent origin. We found significant genetic diversity among landraces. The variation present among landraces belonging to the Zucchini group was larger than that of the commercial cultivars. Cluster, principal coordinate and population structure results suggested that the variation of the Spanish landraces has not been extensively used in breeding. Commercial summer squashes can therefore benefit from this underexploited variability, especially from certain landraces that already display favourable commercial traits.

Background: Cucurbita pepo belongs to the Cucurbitaceae family. The "Zucchini" types rank among the highest-valued vegetables worldwide, and other C. pepo and related Cucurbita spp., are food staples and rich sources of fat and vitamins. A broad range of genomic tools are today available for other cucurbits that have become models for the study of different metabolic processes. However, these tools are still lacking in the Cucurbita genus, thus limiting gene discovery and the process of breeding.Results: We report the generation of a total of 512,751 C. pepo EST sequences, using 454 GS FLX Titanium technology. ESTs were obtained from normalized cDNA libraries (root, leaves, and flower tissue) prepared using two varieties with contrasting phenotypes for plant, flowering and fruit traits, representing the two C. pepo subspecies: subsp. pepo cv. Zucchini and subsp. ovifera cv Scallop. De novo assembling was performed to generate a collection of 49,610 Cucurbita unigenes (average length of 626 bp) that represent the first transcriptome of the species. Over 60% of the unigenes were functionally annotated and assigned to one or more Gene Ontology terms. The distributions of Cucurbita unigenes followed similar tendencies than that reported for Arabidopsis or melon, suggesting that the dataset may represent the whole Cucurbita transcriptome. About 34% unigenes were detected to have known orthologs of Arabidopsis or melon, including genes potentially involved in disease resistance, flowering and fruit quality. Furthermore, a set of 1,882 unigenes with SSR motifs and 9,043 high confidence SNPs between Zucchini and Scallop were identified, of which 3,538 SNPs met criteria for use with high throughput genotyping platforms, and 144 could be detected as CAPS. A set of markers were validated, being 80% of them polymorphic in a set of variable C. pepo and C. moschata accessions.Conclusion: We present the first broad survey of gene sequences and allelic variation in C. pepo, where l

The aim of this work was to study the changes in volume, density, porosity and shape factors of pumpkin tissue during osmotic dehydration (OD) and air drying (AD). Pumpkin cylinders with length/diameter ratio of 5/3 were used. OD experiments were carried out with solutions of sucrose, sodium chloride and mixtures of both solutes at different temperatures. AD experiments were conducted at 70 °C. Volume of samples decreased linearly with weight reduction (WR). Bulk density varied in a restricted range (5-13%) during dehydration and for all the methods maximum values were found. Particle density increased during both processes. Porosity increased at advanced degrees of dehydration, showing a minimum value at the beginning of OD and AD. The proposed models to evaluate shrinkage, bulk and particle densities and porosity from WR were satisfactorily applied. Image analysis showed that shrinkage of samples during OD was isotropic. Pumpkin cylinders increased elongation and decreased roundness and compactness during osmotic dehydration. © 2010 Elsevier Ltd. All rights reserved.

Background: Cucurbita pepo belongs to the Cucurbitaceae family. The "Zucchini" types rank among the highest-valued vegetables worldwide, and other C. pepo and related Cucurbita spp., are food staples and rich sources of fat and vitamins. A broad range of genomic tools are today available for other cucurbits that have become models for the study of different metabolic processes. However, these tools are still lacking in the Cucurbita genus, thus limiting gene discovery and the process of breeding.Results: We report the generation of a total of 512,751 C. pepo EST sequences, using 454 GS FLX Titanium technology. ESTs were obtained from normalized cDNA libraries (root, leaves, and flower tissue) prepared using two varieties with contrasting phenotypes for plant, flowering and fruit traits, representing the two C. pepo subspecies: subsp. pepo cv. Zucchini and subsp. ovifera cv Scallop. De novo assembling was performed to generate a collection of 49,610 Cucurbita unigenes (average length of 626 bp) that represent the first transcriptome of the species. Over 60% of the unigenes were functionally annotated and assigned to one or more Gene Ontology terms. The distributions of Cucurbita unigenes followed similar tendencies than that reported for Arabidopsis or melon, suggesting that the dataset may represent the whole Cucurbita transcriptome. About 34% unigenes were detected to have known orthologs of Arabidopsis or melon, including genes potentially involved in disease resistance, flowering and fruit quality. Furthermore, a set of 1,882 unigenes with SSR motifs and 9,043 high confidence SNPs between Zucchini and Scallop were identified, of which 3,538 SNPs met criteria for use with high throughput genotyping platforms, and 144 could be detected as CAPS. A set of markers were validated, being 80% of them polymorphic in a set of variable C. pepo and C. moschata accessions.Conclusion: We present the first broad survey of gene sequences and allelic variation in C. pepo, where l