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Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

El estrés por salinidad es uno de los problemas ambientales con mayor impacto en la agricultura, ya que provoca cambios morfológicos, fisiológicos y genéticos en las plantas. Considerando el gran impacto de la salinidad, se buscan alternativas para mitigar el estrés en las plantas, en especial por cloruro de sodio (NaCl). Los productos a base de silicio (Si) tienen la capacidad de mejorar el crecimiento y desarrollo de las plantas, al estar expuestas en condiciones salinas. El objetivo de esta investigación fue evaluar la interacción NaCl-Si en la emergencia de plántulas de tres variedades de tomate. El diseño experimental fue completamente al azar con arreglo factorial de 32, donde el factor A fueron las concentraciones de cloruro de sodio (0 mM, 25 mM, 50 mM) y el factor B, las diluciones de Si (0 mM, 1 mM, 2 mM). Los resultados indican que las variedades de tomate fueron impactadas de diferente manera por la interacción NaCl-Si. En condiciones no salinas (0 mM de NaCl) el Si incrementó el crecimiento de tomate cherry y saladette, mientras que en condiciones de salinidad moderada (25 mM de NaCl) sólo el tomate saladette fue beneficiado.

Thermotherapy has been proved to be an effective and easy to apply method to achieve a stimulation in germination and development of seedlings, in results of laboratory evaluations, based on dry heat to soybean seeds for the germination stimulation of these seeds and their vigor. The best exposure time to the treatment that enhanced germination and the characters associated to this, in nine Cuban soybean cultivars was determined. It was proved that the most effective thermotherapeutic treatment for the studied variables was the one resulting from five hours of exposure of the seeds to 50 °C. In this work, the field results are presented with such treatment of five hours of exposure to 50 °C in soybean seeds prior to sowing, under summer sowing of 2020, to evaluate the effect on morphological characters, yield components and real yield in seven Cuban soybean cultivars (Glicyne max L.). The trial of the present research was carried out in agricultural areas of the Agricultural Services Department of INCA, in the period from July 13 to November 5, 2020. The thermotherapeutic seed treatments of 50 °C during 5 hours define significant productive increases to any cultivar in summer sowing, at the time of harvesting executed to each cultivar according to its productive cycle. [ABSTRACT FROM AUTHOR]

This research aimed to assess the impact of applying mountain microorganisms (MM) on coffee seedling production. Two nurseries (A and B) were used with weekly and bi-weekly treatment applications. Plant height, leaf and root lengths, and dry matter content (DM) were measured. Results showed that Nursery A, with weekly treatments, exhibited greater height and leaf length growth compared to Nursery B. In the initial measurement, Nursery A accumulated more leaf DM than Nursery B. However, over time, both nurseries experienced a decline in DM. Root length variability was observed in both nurseries throughout the measurements. Treatments with MM from forest and coffee systems in Nursery A showed higher leaf DM accumulation in the initial measurement. In conclusion, MM application, especially with higher frequency, promoted coffee seedling growth. The results emphasize the need for detailed analysis to understand optimal root development conditions. The decline in DM over time is a natural response to active growth, indicating increased nutritional requirements. These findings support MM-based strategies for sustainable coffee seedling production. [ABSTRACT FROM AUTHOR]

Increasing water deficits and warming temperatures due to climate change threaten agricultural systems in the Peruvian Andes, where environmental conditions are themselves challenging. Lepidium meyenii Walpers also known as "maca" is an endemic root crop that can tolerate adverse conditions such as low temperatures and high UV radiation, but little is known about its response to drought. This study aimed to test the effect on maca germination and early seedling growth of water restriction under two maximum temperatures: 15 °C (current scenario) and 20 °C (warming scenario). Water restriction had either a direct or a temperature-dependent effect on germination and above-ground seedling growth, which was greater at 15 °C. By contrast, its effects on seedlings growing at 20 °C were completely overcome by faster germination, initial growth, and biomass acquisition. The results are consistent with those from other crops and contribute to the understanding of how climate change is affecting high-mountain agriculture. [ABSTRACT FROM AUTHOR]

Copyright of Agronomía Colombiana is the property of Universidad Nacional de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

En Ecuador, la producción agrícola destinada al consumo depende en gran medida del cultivo y trasplante de plántulas obtenidas mediante un proceso manual que implica la colocación individual de semillas en las cavidades de almácigos. Esta investigación se enfoca en el diseño de un prototipo de sembradora para la colocación semiautomática de semillas con el objetivo de reducir el tiempo dedicado a esta actividad en el proceso agrícola. El prototipo, que incorpora componentes eléctricos, neumáticos y mecánicos, presenta versatilidad para adaptarse a semillas de cuatro a diez mm. La composición óptima se determinó mediante un enfoque deductivo y exploratorio. Las pruebas confirmaron que el prototipo reduce el tiempo de siembra manual de cinco a tres minutos, especialmente en situaciones que requieren grandes cantidades de almácigos de manera continua, lo que representa una disminución del 40% en el tiempo por bandeja sembrada. Además, es esencial considerar el costo asociado, aproximadamente ochocientos diez dólares, lo que posiciona esta propuesta como una inversión altamente rentable. Este resultado sugiere un beneficio significativo para el sector agrícola al implementar este dispositivo en el proceso de siembra, especialmente para emprendedores y pequeños productores.

Tara spinosa (Molina) Britton & Rose (Fabaceae), known as "tara" or "taya", probably native to Peru, grows from sea level to 3000 m a.s.l., and is important for the tannins and gum contained in its pods and seeds, respectively. The objectives were to define and validate morphological seedling descriptors and to characterize "tara" germplasm from the Cajamarca region (58 entries from nine provinces) by integrating fruit, seed and seedling descriptors. Seven highly discriminating seedling descriptors were identified, with cotyledon descriptors being the most important. Characterization of "tara" from Cajamarca germplasm with 18 integrated descriptors (six fruit, five seed and seven seedling) allowed a new clustering, in seven groups, indicating close variability (86% duplicates). [ABSTRACT FROM AUTHOR]

In order to monitor the morphologic indicators and the organisms caused of plagues associated to Moringa oleifera two tests were conducted: nursery and field. The treatments were represented by six moringa origin, collected in three provinces of the country. In nursery, a total of 396 polyethylene bags were used in a completely random design, with 66 repetitions. In field, a random block design with three replications was applied. In both test the arthropods and associated pathogens were monitoring. The phytosanitary damage and morphologic indicators of the crop growing were evaluated. In nursery phase, the plants did not have economic damages by harmful organisms and showed favorable grow indicators. Therefore, in field, the new transplant plantlets were affected by strong attacks of Atta insularis, which caused defoliation and plantlets loss. The survival has similar average ranges in all origins. The count of branches was better in the origins 4 and 6 with 4.40 and 4.18, respectively. The height, at 120 days after the transplant, showed sizes higher than 145 cm, in the origins 2 and 6. The higher stem thickness (31.2 mm) was showed in the origin 2. It is concluded that the evaluated origins, according to their morphologic indicators performance have potentialities for their use. It is recommended to continue with the phytosanitary alertness of the crop and to regulate the forage activity of A. insularis until achieving the moringa establishment. It should be alert in the fruiting phase of the incidence of Gitona sp. fly to minimize the damage to the seeds, to avoid the secondary presence of pathogens and to allow the harvest of healthy seeds. [ABSTRACT FROM AUTHOR]

Copyright of Revista Novasinergia is the property of Revista Novasinergia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Terra Latinoamericana is the property of Sociedad Mexicana de la Ciencia del Suelo A.C. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Eichhornia crassipes is an aquatic plant present in bodies of water with excess nutrients, which favors its growth and causes negative environmental and social impacts, a situation that promotes the search for alternatives for its use. The objective was to evaluate the physical and chemical properties of E. crassipes as a substrate for germination in vegetables and in the form of bocashi for radish development. As a germinative substrate, dry and ground E. crassipes was mixed in four different proportions with compost and agrolite, considering a control treatment of 100 % E. crassipes. Under a completely randomized design, seeds of Solanum lycopersicum, Cucurbita pepo and Cucumis sativus were germinated. In another trial, a bochashi was carried out with fresh E. crassipes, which was applied at doses of 0 %, 15 %, 30 % and 45 % in Raphanus sativus. Germination varied in the treatments with E. crassipes from 0-99 %. Amounts of 25 % and 50 % of E. crassipes showed the best physical and chemical characteristics as substrates. Bocashi made with E. crassipes showed advantages in radish bulb quality, indicating a dose of 15 % as recommended for its production. [ABSTRACT FROM AUTHOR]

Los bioestimulantes a base de algas marinas tienen el potencial de mitigar problemas de estrés siendo opción para mejorar la calidad y el rendimiento de los cultivos. Sin embargo, la aplicación de algas marinas como ingrediente activo en bioestimulantes sobre plántulas de cacao nacional es muy poca documentada. Por lo tanto, esta investigación tuvo como objetivo evaluar el efecto de un bioestimulante a base de algas marinas (Ecklonia maxima), sobre las características fenológicas en plantas de cacao en etapa de vivero en el cantón Machala, provincia El Oro. En base a esto se planteó generar un diseño homogéneo completamente al azar (4x4), el cual contó con 16 unidades experimentales; en las cuales se encuentran 4 plantas por unidad experimental, dando así un total de 64 plantas por todo el diseño, siendo el factor de estudio las dosificaciones: TA (50%), TB (100%), TC (150%) y TD (control). La utilización bioestimulante indica que la dosis en exceso (150%) dentro de las plántulas de cacao no es conveniente utilizarla debido a que influyó de manera adversa, pues en todas las variables morfológicas el tratamiento con el bioestimulante al 50 % presentó las medias más altas en las plántulas.

La prolina es un aminoácido que se acumula en plantas en respuesta a condiciones de estrés. Se ha reportado que la aplicación exógena de prolina aumenta la tolerancia al estrés. Se realizó un experimento para evaluar el efecto de diferentes soluciones de prolina exógena aplicadas a plántulas de melón cultivadas en estrés salino. Se evaluaron cuatro concentraciones de prolina: 0, 5, 10 y 20 mM. Las plantas se cultivaron con una conductividad eléctrica de 8,0 dS m-1. Las plantas tratadas con prolina 10 y 20 mM tuvieron un mayor contenido de prolina así como un aumento de los parámetros de crecimiento. El contenido de clorofila tuvo el valor más alto para el tratamiento 10 mM. Los resultados sugieren que la aplicación exógena de prolina 10 y 20 mM permite aumentar la respuesta de tolerancia al estrés salino.

Copyright of Revista Mexicana de Ciencias Agrícolas is the property of Instituto Nacional de Investigaciones Forestales, Agricolas y Pecuarias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background and aims: Zephyranthes tubispatha is a South American species with ornamental and pharmacological potential. We aimed to study: 1) attributes of fruits, seeds, seed-seedling transition substages, normal and abnormal seedlings; 2) germination due to the effect of different storage periods, seeding times, and exposure to supra-optimal temperatures; and 3) plant vigor. M&M: Samples harvested between 2018 and 2022 (Buenos Aires, Argentina) were used. Fruits and seeds were characterized morphometrically and seminal reserves histochemically. Substages during the seed-seedling transition were defined, and normal and abnormal seedlings were morphologically described. The germination of seeds from different storage periods, seeding times, and thermal conditions was evaluated. Changes in seed viability, electrolyte loss, and plant vigor were studied. Results: In the seeds, lipids and proteins were detected as reserves. Normal and abnormal seedlings and the seed-seedling transition with five substages were described. Seeds of up to 10 months of storage, different seeding times and thermal conditions presented high germination percentages. High temperatures thermoinhibited germination, but did not affect subsequent plant survival. Conclusions: Storage for more than one year showed increased seed mortality and seedling anomalies. The seeding moment conditioned the germination response to the heat treatments, and thermoinhibition did not affect the vigor of the plants produced. [ABSTRACT FROM AUTHOR]

Contextualization: pea is a legume with a high nutritional potential because it is a source of protein and is widely cultivated throughout the world. Knowledge gap: Even though the percentage of germination of pea seeds is high, this germination is uneven since most legumes have different degrees of dormancy, which generates plants of different sizes and with gaps in the phenological stages of the crop. Purpose: evaluate the effect of different doses of gibberellins [GAs] on the ger mination and growth of pea seeds, variety 'Santa Isabel'. Methodology: through a completely randomized design [DCA] with six treatments, which corresponded to the different doses of gibberellins applied [0, 200, 400, 600, 800 or 1000 mg L-1], every germination variable and subsequent growth of pea seedlings were evaluated. Results and conclusions: The application of GAs decreases the average germination time. The GAs generated seedlings with more height, but with thinner stems; while the seedlings from seeds without GAs were smaller, but with greater fresh and dry mass of leaves, and with greater aptitude for transplanting. The application of GAs in pea seeds did not affect the total dry and fresh mass of the pea seedlings, neither the MSR nor the MFR. The GAs promoted the redistribution of photo-assimilates by increasing the dry and fresh mass of stems at the expense of decreasing the dry and fresh mass of leaves and stipules. As the dose of gibberellins increased, the translocation of photo-assimilates from the seed to the stem specifically increased. [ABSTRACT FROM AUTHOR]

O Brasil apresenta uma grande biodiversidade de vegetais, aproveitadas pela população como fitoterápicos, dos quais se destaca o agrião Nasturtium officinale, o mesmo é aproveitado principalmente para o consumo humano, sendo a sua parte aérea a mais aproveitada. Objetivou-se com esse trabalho avaliar a emergência e o crescimento inicial do agrião Nasturtium officinale em diferentes tipos de substratos. A pesquisa foi realizada no Departamento de Tecnologia e Ciências Sociais da Universidade do Estado da Bahia. O experimento foi conduzido em casa de vegetação, sendo os tratamentos: T1 areia, T2 esterco/ areia (2:1), T3 areia /pó de serra (2:1), T4 esterco/pó de serra (2:1), e T5 substrato comercial e dez repetições, totalizando 50 amostras. As variáveis avaliadas foram: emergência das plântulas, número de folhas, comprimento da raiz (cm), massa fresca da parte aérea e massa seca da parte aérea. O Tratamento 5 apresentou maior eficiência e uniformidade na porcentagem de emergência e quando avaliadas as medias da variável número de folhas, massa fresca e massa seca da parte aérea, o tratamento 5 apresentou diferença estatística significativa dos demais tratamentos e quando avaliado o comprimento da raiz o tratamento 3 e 5 apresentaram as melhores médias.

Introducción y objetivos: Zephyranthes tubispatha es una especie sudamericana con potencial ornamental y farmacológico. Se planteó completar el conocimiento de su reproducción por semillas, respecto a: 1) atributos de frutos, semillas, subestadios de transición semilla-plántula, plántulas normales y anormales; 2) la germinación por efecto de diferentes periodos de almacenamiento, momentos de semillazón, y exposición a temperaturas supraóptimas; y 3) el vigor de plantas. M&M: Se utilizaron muestras cosechadas entre 2018 y 2022 (Buenos Aires, Argentina). Se caracterizaron morfométricamente frutos y semillas, e histoquímicamente las reservas seminales. Se definieron subestadios durante la transición semilla-plántula, y describieron morfológicamente plántulas normales y anormales. Se evaluó la germinación de semillas prevenientes de diferentes periodos de almacenamientos, momentos de semillazón y condiciones térmicas. Se estudiaron cambios en la viabilidad de semillas, pérdida de electrolitos, y el vigor de plantas. Resultados: Las dimensiones de frutos y número de semillas difirieron a lo reportado bibliográficamente, y coincidieron en color y textura seminal. Se detectaron lípidos y proteínas como reservas del endosperma. Se describieron cinco subestadios de transición semilla-plántula, plántulas normales y anormales. Semillas de hasta 10 meses de almacenamiento, diferentes momentos de semillazón y condiciones térmicas presentaron altos porcentajes de germinación. Las altas temperaturas termoinhibieron la germinación, pero no afectaron la posterior supervivencia de plantas. Conclusiones: El almacenamiento por más de un año evidenció aumento en la mortalidad de semillas y anomalías en plántulas. El momento de semillazón condicionó la respuesta germinativa a los tratamientos térmicos y la termoihibición no afectó el vigor de plantas producidas.

El cultivo del ñame es de alta importancia para la seguridad alimentaria de las familias rurales en la región Caribe de Colombia. Uno de los principales problemas tecnológicos que enfrentan los pequeños productores es la baja calidad y disponibilidad de la semilla para las siembras. El presente trabajo se realizó con el objeto de evaluar la tecnología de producción de minitubérculos en plántulas de ñame generadas a partir de esquejes, mediante inducción con rizobacterias. Para ello, inicialmente se evaluó in vitro la capacidad de producción de f itohormonas de tres rizobacterias, identif icadas con los códigos DCR11 (Azotobacter vinelandii), DSC21 (Brevibacillus laterosporus) y DSC1 (Bacillus licheniformis), y una vez comprobada su capacidad, se estableció un experimento bajo condiciones de casa de malla para inducir, con las rizobacterias, la producción de minitubérculos en las plántulas de ñame, bajo tres niveles de sombreamiento. Se utilizó un diseño experimental completamente al azar con arreglo en parcelas subdivididas y tres repeticiones, en donde la parcela principal correspondió a los niveles de sobreamiento (0, 65 y 80%), las subparcelas a las tres rizobacterias (DCR11 A. vinelandii, DSC1 B. licheniformis, DSC21 B. laterosporus) y las sub-subparcelas a las dosis del inóculo (0, 2, 4 y 6 mL pl-1). Los resultados in vitro demostraron el potencial de las rizobacterias para producir citoquinas y auxinas. En casa de malla se logró evidenciar la capacidad de producción de minitubérculos por parte de las plántulas de ñame, en donde las rizobacterias DSC1 B. licheniformis y DSC21 B. laterosporus mostraron mayor capacidad de inducción. A partir de los resultados se demostró la viabilidad de producción de minitubérculos en plántulas de ñame bajo condiciones de casa de malla mediante inducción con rizobacterias, por lo que se recomendó su validación a nivel semicomercial como estrategia para la producción masiva de minitubérculos de ñame, como alternativa para la siembra de cultivos comerciales.

Cultivar sus propias plántulas por medio de almácigos (germinaderos) orgánicos ofrece muchas ventajas, incluido el control sobre variedades, cantidades, fechas de siembra y trasplante. Esta guía del agricultor describe cómo cultivar, de manera eficiente y efectiva, plántulas de flores y hortalizas en granjas orgánicas utilizando prácticas ambientalmente responsables.

Tomato is one of the main horticultural products in Argentina. Its cultivation is intensive in the use of fertilizers and pesticides, which negatively impact the environment. The chemical fertilizers commonly used are, to some extent, gradually being replaced by liquid biofertilizers. A liquid biofertilizer (bioslurry) made from goat manure, fresh plant residues, and some mineral inputs was physicochemically characterized. To evaluate its effect on tomato (Solanum lycopersicum L.) performance, two trials were conducted between October and November 2020: a seed germination test with increasing bioslurry dilutions (0 to 15%); and another trial in a greenhouse located in Luján de Cuyo, Mendoza, to evaluate the effect of different doses of bioslurry (5, 10 and 15%), compared to a commercial fertilization plan for seedlings in plastic trays. The experimental design used was completely randomized plots in both cases. Bioslurry at concentrations above 5% negatively affected tomato seed germination. The biofertilizer achieved a nutritional effect on seedlings compared to the unfertilized control. However, this effect was inferior to the treatment with commercial fertilizers. It is advisable to initiate applications of bioslurry after seedlings have emerged. Further studies are needed on biofertilizer use concentrations, doses, application frequencies, and suitability for different crops. Also, to achieve the effect of a commercial fertilization program, it will be necessary to combine enriched bioslurry with other bio inputs that complement plant nutrition. [ABSTRACT FROM AUTHOR]

A comparative study for evaluating the influence of metal oxide nanoparticles (MONPs) (Al2O3, TiO2, and SiO2) on seed germination and seedling growth in okra was implemented under water deficit stress stimulated by PEG-6000. The results revealed that additive of SiO2 nanoparticles (SNPs) and Al2O3 (ANPs) have significant positive effect on seeds germination, while a reduction of that were observed by using TiO2 nanoparticles (TNPs) at 50 mg.L-1 concentration under 5% PEG-6000 stimulated drought stress as compared to that without MONPs. Further, relative to non-MONPs treatment, all the tested MONPs dramatically enhanced the drought stress tolerance in okra seedlings due to the improvement of morphological growth despite a few traits were inhibited under certain water deficiency to some degree. Improvement of drought resistance induced by TNPs and ANPs were found to be higher than that by SNPs. Our finding provides a promising approach to cope with water scarcity, as application of metal oxide nanoparticles to be a potential option to protect okra plants against drought stress. [ABSTRACT FROM AUTHOR]

El objetivo de este estudio fue evaluar la influencia de los bioestimulantes QuitoMax® y OPLANT+® en la germinación y el crecimiento de las plántulas de tomate (Solanum lycopersicumL.). En condiciones de laboratorio, se realizó un experimento en esquema factorial (7 × 3), en un diseño completamente aleatorizado, con tres repeticiones. Tres concentraciones de QuitoMax® (2,5, 5 y 10 mg/L), tres diluciones de OPLANT+® (1:40, 1:50 y 1:60 (v:v)) y un control (agua) se combinaron con tres tiempos de imbibición (TI) (10, 20 y 30 min). Otro experimento se realizó en condiciones de campo en bloques al azar, con tres tratamientos y siete réplicas. Un control (sin bioestimulantes), semillas embebidas en 5 mg/L de QuitoMax® por 20 min y 1:60, v:v de OPLANT+® por 30 min. Los resultados indican que el QuitoMax® y el OPLANT+® mostraron efectos similares en la germinación en los tratamientos con 5 mg/L por 20 min y 1:60 por 30 min, respectivamente. La masa seca de la parte aérea y de las raíces se incrementó en 24 % y 98 % con el QuitoMax®, y 11 % y 90 % con el OPLANT+® en relación con el tratamiento control. Sin embargo, el QuitoMax® fue más promisorio en la promoción del crecimiento de las plantas que las sustancias húmicas. Este estudio sugiere que ambos bioestimulantes son eficientes y viables para estimular la germinación y el crecimiento de las plantas de tomate, lo cual sugiere su utilización en la producción sostenible en estas etapas del cultivo.

Background and aims: Zephyranthes bifida is a native species of the Pampas ecoregion, with ornamental and medicinal potential. In this work, the seedling was studied for the first time and its seeds were characterized. The objectives were to describe the cotyledon and the first leaf and to provide some anatomical characteristics, as well as to provide information about the embryo/endosperm relationship and the type of reserve substances in the seed. M&M: Seed reserve substances were determined by histochemical tests and the embryo/endosperm surface ratio was obtained with ImageJ. In seedlings, morphological structures were described, using Tillich's terminology (1995; 2007), and some anatomical characteristics. Phenological stages were established for ten days from germination. Results and conclusions: Lipid and protein and lack of starch were determined in embryo and endosperm. In seedlings, the cotyledon is subdivided into a hypophyll and a hyperphyll. Hypophyll presents a ring through which the first eophyll emerges. The distal part of the cotyledonary hyperphyll is completely inserted in the seed, has a haustorial function and has two vascular bundles. Proximal part of cotyledonary hyperphyll has photosynthetic activity and has two vascular bundles too. In the first eophyll, hyperphyll has three vascular bundles. The primary root is attached to the base of the cotyledon through a very short hypocotyl, which in its basal part has rhizoids. Four stages were defined during germination from the emergence of hypophyll, hyperphyll and first eophyll. [ABSTRACT FROM AUTHOR]

El cultivo del cacao (Theobroma cacao) en Alto Amazonas ha aumentado sus extensiones en la última década, lo cual demanda plántulas de cacao con buenas raíces. Esta demanda requiere sustratos para la producción de plantas en vivero; sin embargo, en la zona es escaso, por lo que es necesario identificar el volumen de sustrato para obtener plántulas de cacao, con el fin de establecer plantaciones con éxito. El objetivo del estudio fue evaluar el crecimiento de plántulas en vivero, usando diferentes volúmenes de sustratos. El diseño experimental correspondió a Completamente al Azar (DCA) con arreglo en parcelas divididas y dependencias fueron representadas mediante gráficos de regresión lineal y polinómica. Se utilizaron semillas pre germinadas de cacao criollo, se evaluaron a los 15, 45, 75 y 105 días de la emergencia, altura de la planta (cm), número, ancho y longitud de hojas (cm), diámetro del tallo (cm), longitud de raíz principal (cm) y el peso fresco total de plantas (g). Los resultados indican que en volúmenes de 1,5 kg la mayoría de las variables evaluadas en espacial el peso total de las plantas tuvo mejores promedios y ajuste del modelo lineal. Lo que se evidencia un mejor comportamiento en comparación de los otros dos volúmenes de sustrato (1 kg y 2 kg), lo que permite definir parcialmente un estándar del volumen a usar en la producción de plantas en vivero.

Como consecuencia del incontrolable crecimiento urbano y del sector industrial, se ha estado atendiendo y soportando un grave problema de salubridad como son los incrementos constantes y masivos de las aguas residuales, por lo que se propone su utilización para el riego en los viveros forestales. El objetivo de esta investigación fue evaluar tres tipos de agua, empleados en el riego para la producción de plántulas de Pinus oocarpa en la etapa de vivero, con el fin de determinar cuál de estos presenta mejores resultados en la germinación de la misma. El estudio fue realizado en la planta piloto de tratamiento de aguas residuales “Ing. Arturo Pazos Sosa”, localizada en la colonia Aurora II de la zona 13 de la ciudad de Guatemala. La investigación se realizó mediante un diseño completamente al azar (DCA), de 3 tratamientos con 4 repeticiones. Después de evaluada la germinación, los mejores resultados se obtuvieron al emplear el riego con agua potable (Tratamiento 3).

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Agronomía Colombiana is the property of Universidad Nacional de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Ciencia y Tecnología Agropecuaria is the property of Agrosavia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introducción. La caracterización de cultivares de Rubus spp. tolerantes al estrés hídrico en campos experimentales es complicado por la dificultad de controlar los factores externos del medio ambiente donde son instalados. La inducción de estrés in vitro es una herramienta eficiente para estudiar los mecanismos de respuesta de las plantas y se emplea en los programas de mejoramiento para la selección de genotipos tolerantes al estrés hídrico. Objetivo. Evaluar la respuesta morfológica y fisiológica in vitro de los explantes en tres cultivares y la accesión silvestre de Rubus spp. bajo condiciones de estrés hídrico simulado con manitol. Materiales y métodos. El estudio se realizó en el Laboratorio de Biología de la Universidad Nacional Toribio Rodríguez de Mendoza de Amazonas, Perú, durante el año 2020. Se empleó un diseño completamente al azar con arreglo factorial (Factor A: cuatro genotipos y Factor B: potenciales hídricos simulados con manitol: 0, -0,2, -0,3 y -0,4 MPa) y cuatro explantes por unidad experimental. Resultados. Los cultivares respondieron de manera distinta bajo estrés hídrico simulado con manitol. Los cultivares Navaho y Tupy registraron mayor tolerancia. Conclusión. Los rasgos morfológicos y fisiológicos relacionados con la longitud de raíz, el contenido hídrico de brote, raíz y hoja permitieron identificar cultivares de Rubus spp. tolerantes al estrés hídrico simulado con manitol en la fase vegetativa.

Copyright of Roca: Revista Científico-Educacional de la Provincia de Granma is the property of Universidad de Granma, Departamento Editorial and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

El presente estudio se realizó en la Unidad de Manejo para la Conservación de la Vida Silvestre denominada Vivero El Manglar en el municipio Acapulco, Guerrero, México. El objetivo fue evaluar la eficiencia de propagación asexual por medio de material vegetativo (estacas) como propágulos de Laguncularia racemosa. Se utilizó la técnica de enraizamiento de estacas para la propagación asexual de manglares; de las plantas madre, se recolectaron 500 estacas entre 50 y 100 cm de longitud y un diámetro de 5 a 10 cm. Se obtuvo 54 % de supervivencia en la propagación, pero con escasa formación de brotes apicales y de raíces adventicias. Se comparó el número de brotes con el de raíces adventicias mediante la prueba de correlación de Tau de Kendall de lo que resultó un valor de 0.062 y significancia de p= 0.200 mayor que p > 0.05, lo que indica correlación positiva muy débil y poco aceptable; se confirmó que la propagación vegetativa por estacas no es las más eficiente para reproducir ejemplares de L. racemosa en condiciones de vivero. Para dar soporte al análisis anterior, se realizó la prueba de Friedman, que dio un valor de significancia de 0.000 inferior a p ≤ 0.05, y se observaron diferencias significativas de interacción entre ambas variables. El presente estudio demostró que la propagación asexual de L. racemosa tuvo una eficiencia regular, por lo que será necesario dar continuidad con experimentos de reproducción asexual y sexual.

O objetivo deste trabalho foi analisar os efeitos de substratos e bioestimulante na germinação e desenvolvimento de lentilha. Cada tratamento continha 4 repetições, foram avaliados índice de velocidade de emergência, altura das plantas, comprimento de raiz e pesos de massa seca de raiz e parte aérea. Os tratamentos continham os substratos solo, areia e torta de filtro e combinações (nas proporções 1:1), e a partir destes substratos também foram avaliados tratamentos com meia dose e dose do bioestimulante Celleron Seeds. Os dados foram submetidos a análise de variância e posterior Teste de Tukey a 5% de significância no programa SASM AGRI. Os tratamentos não afetaram a porcentagem de emergência das sementes. O uso do bioestimulante na dose recomendada e da Torta de filtro se mostraram promissores na altura da parte aérea das plântulas, porém não afetaram o comprimento de raiz e a massa seca da parte aérea, já o peso da massa seca de raiz foi afetado com a meio dose do bioestimulante.

Copyright of Avances is the property of Instituto de Informacion Cientifica y Tecnologica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Bacillus subtilis exhibits antagonistic activity against plant pathogens. In the present study, the fungi associated with damping off in zucchini squash seedlings were identified and the efficacy of B. subtilis strain QST 713 was evaluated against the combined infection of the isolated fungi. The pathogens were isolated from zucchini squash seedlings with symptoms of damping off. Seedlings of zucchini squash var. Gray zucchini were inoculated with propagules of three pathogens at a concentration of 4×105 CFU of each pathogen. The effectiveness of B. subtilis (2, 4 y 6×107 UFC mL-1) was evaluated and compared with methyl thiophanate + propamocarb hydrochloride (preventive and curative). The incidence was assessed at three, six, nine and 12 days (dai). Three fungi out of 100 isolates were isolated and identified: Phytophthora capsici (62%), Rhizoctonia solani (26%) and Fusarium oxysporum (12%). The efficiency of B. subtilis was observed, with a reduction in the incidence of the disease as the concentration was increased. Twelve days after inoculation, the incidence of damping off in B. subtilis treatments ranged from 18.3 to 41%. The B. subtilis treatment (6×107 CFU mL-1) was statistically equal to methyl thiophanate + propamocarb hydrochloride (curative). The strain QST 713 of B. subtilis controlled 81.7% the damping off of zucchini squash seedlings, applied preventively at a concentration of 6×107 CFU mL-1. [ABSTRACT FROM AUTHOR]

Las semillas de hortalizas de hoja son más sensibles al ataque de patógenos, por lo que es necesario estudiar el potencial fisiológico de las misma. Para ello se evaluó la calidad fisiológica de semilla de acelga (Fordhook Giant), ajo porro (Large American Flag y American Flag) y espinaca (New Zealand y Viroflay). Para ello se determinó el porcentaje de germinación, porcentaje de emergencia (PE), velocidad de emergencia (VE), índice de velocidad de emergencia (IVE), microbiota y metabolitos secundarios por cromatografía de capa fina. Para las evaluaciones de germinación, emergencia e identificación de patógenos se realizaron 4 repeticiones usando 100 semillas por repetición. Los resultados muestran un bajo desempeño fisiológico en semillas de espinaca New Zealand y Ajo porro (Large American Flag y American Flag), lo que se vio reflejado en las variables de GE (%), PC (%), VE e IVE debido a la presencia de hongos de los géneros Rhizopus, Fusarium, Penicillium, y las bacterias, que redujeron el vigor de las plántulas, así como un número importante de plántulas anormales, mientras que las semillas de espinaca Viroflay y Acelga Fordhook Giant presentaron una mejor germinación al primer conteo, sin embargo, los problemas relacionados con el vigor se reflejaron en las variables PE, VE, IVE, y con alto desarrollo de plántulas anormales, adicionalmente se detectó la presencia de los flavonoides el cual se asoció a una menor incidencia de Penicillium sp., en la semilla de espinaca viroflay aumentando la GE en el primer conteo y la germinación total.

Effective identification of plant species is fundamental for a better understanding of natural regeneration. However, classical taxonomic methods largely rely on reproductive structures, which are frequently absent in juvenile individuals. To overcome this difficulty, several approaches may be applied, a good example being external anatomy of the leaf epidermis (hereafter micro-morphology). Therefore, the aim of this paper was to test whether the former cited trait can provide suitable distinctive characters for identification of tree species seedlings in general. We chose six common species from the Southern Brazil Seasonal Forest to proceed with our tests, from which we collected two to four leaves of randomly selected seedlings (five replicates/species). We, then, printed leaf epidermis on a microscope slide with instant adhesive and analyzed for diagnostic features. Our analyses showed that several anatomical characteristics of the leaf surface are distinct enough to allow a correct species identification, such as the shape of the anti-clinal walls of epidermal cells, the shape of stomata, and the presence/absence of glands and cuticle. Hence, the conclusion of this study is that leaf epidermal anatomy can be used as a source of diagnostic characteristics to correctly identify the seedlings of forest species.

Introducción. La disponibilidad de agua para la producción agrícola es esencial. La producción de maíz, sujeta al periodo de lluvias, en México supera el 70%. En las regiones agrícolas de la península de Yucatán se reportan producciones en condiciones de bajas precipitaciones o muy erráticas, que pueden provocar pérdidas totales. Una condición crítica para el establecimiento de un cultivo es contar con la humedad necesaria que permita la germinación. Objetivo. El objetivo del presente trabajo fue evaluar materiales de maíz bajo condiciones de estrés hídrico simulado por medio de soluciones osmóticas con la finalidad de identificar los que toleren estas condiciones. Materiales y métodos. El estudio se llevó a cabo en el Campo Experimental Mocochá del Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias, durante el 2017; abarcó la fase de germinación y establecimiento. Se emplearon veinticinco materiales de maíz bajo un diseño completamente al azar con arreglo factorial. Se realizó una prueba de germinación bajo dos condiciones de estrés simulado por medio de PEG 8000 (-0,5 y -0,75 MPa), además se empleó un testigo (0 MPa). Se realizaron cuatro repeticiones de veinticinco semillas cada una. Las semillas se expusieron por 24 h al PEG 8000, posteriormente, se hicieron riegos con agua destilada. Se realizaron conteos de las semillas germinadas al séptimo día y se reportó como porcentaje de germinación. En una muestra de diez plántulas de cada repetición, se midió la longitud y el peso, por separado, de la parte aérea y la raíz. Resultados. De los materiales evaluados los híbridos H-563, H-565 y H-568 soportaron estrés de -0,5 MPa, y el H-520, H-567 y HEV3B presentaron germinación con -0,75 MPa y resaltaron en todas las variables evaluadas. Conclusión. Es posible identificar materiales que toleraran las condiciones de estrés durante la etapa de germinación.

La fragmentación es de nida como el proceso de trasformación de un hábitat natural en parches de menor área, aislados entre sí e inmersos en matrices de menor cobertura vegetal. Los parches resultantes quedan expuestos a las condiciones del ambiente exterior o efectos de borde, que pueden ocasionar cambios en la estructura y regeneración de las comunidades vegetales. En esta investigación se evaluó el efecto de borde sobre la estructura, diversidad y potencial de regeneración de plantas leñosas en dos fragmentos de bosque seco. Se registró un proceso activo de regeneración natural, sin embargo, no se encontró un efecto de borde sobre las variables estudiadas para ambos fragmentos. La ausencia de efecto de borde podría estar dada por el tiempo transcurrido desde la formación del fragmento. Durante este tiempo han estado activos los procesos de regeneración, dando lugar a una vegetación de estructura y composición similar en todo el bosque. También se observó que las matrices de estos fragmentos constituyen una barrera para su expansión y conectividad, y para superarla se hace necesaria la implementación de estrategias que favorezcan la dispersión de semillas hacia el exterior y, se optimicen las condiciones para la germinación y el establecimiento de los nuevos propágulos.

Alnus acuminata H.B.K, comúnmente llamado “aliso”, es una de las especies de mayor importancia por su rápido crecimiento, su utilización en sistemas agrosilvo-pastoriles, agroforestales, aporte de nitrógeno al suelo y madera comercial en el mercado regional. En la presente investigación se presenta una metodología para el proceso de enraizamiento para la generación de plantones clonales a mayor escala comercial de esta especie. El objetivo de estudio fue evaluar el porcentaje de enraizamiento de estaquillas utilizando brotes juveniles de 20 cm de longitud y 1 cm de área foliar (se utilizó la parte media y apical), bajo el efecto de tres dosis de ácido indol 3 – butírico (2000, 4000 y 6000 ppm), y tiempo de enraizamiento utilizando microtuneles como estructura de protección. El estudio se realizó en el vivero forestal de la Asociación de Productores Conservacionistas de Molinopampa, ubicado en el anexo de Espadilla. Se utilizó un diseño completamente al azar (DCA), con un arreglo factorial de 2A X 3B, con seis tratamientos y cinco repeticiones por tratamiento. Al término de 66,23 días en promedio, las estaquillas con dosis de 4000 ppm mostraron enraizamientos de 70,0% teniendo como sustrato tierra agrícola, humus de lombriz y arena de río en proporción 2:1:1. Se concluye que si es posible propagar Alnus acuminata (70,0% de enraizamiento), si se utiliza la dosis adecuada de AIB en estaquillas con tres folios.

Copyright of Revista de Ciencias Agricolas is the property of University of Narino, Faculty of Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Plant emergence from seed banks and from asexual reproduction could be strongly influenced by environmental and biological factors. Among environmental factors, animal disturbances deserve special consideration. In this study we test the hypothesis that disturbances resulting from the burrowing activity of Ctenomys affect plant emergence (sexual and asexual) in the south of the cold Puna desert. Richness and abundance of seedlings and sprouts growing in areas disturbed or undisturbed by Ctenomys were recorded at the beginning and at the end of the vegetative season. In general terms, the activity of Ctenomys does not affect richness of emerging species, but does have a significant influence on the type of emergence. Analyses between areas revealed that seedling emergence was significantly higher than sprout emergence in areas showing Ctenomys activity, whereas no significant differences were found between types of emergence in undisturbed areas. Although vegetative emergence was important, plant emergence from seeds appears to be relevant to the recolonization of areas disturbed by Ctenomys. [ABSTRACT FROM AUTHOR]

An experiment was conducted to enhance the turnip seed performance under salinity stress conditions. The impact of priming with an optimized dosage (5 g/l) of KCl and NaCl had been evaluated for enhancing seedling vigor and salt stress tolerance in seedlings of the turnip. Seeds prepared with (5 g/l) of KCl and NaCl solutions were examined at different salinity levels (0, 50, 100, 150, 200)mM of NaCl concerning the early growth stage. The data were analyzed using SPSS windows version 23 (one way ANOVA p ≤ 0.05) to determine the significant difference between treatments and followed Duncan test, p < 0.05 for means comparison. The results have shown that priming with KCl and NaCl were effective in reducing the adverse effects of salinity. A significant (P < 0.05) increase in germination percentage, seed vigor, hypocotyl and radicle length, salt tolerance, and dry weight of the seedlings of seed that priming with (5 g/l) of KCl and NaCl compared to nonprimed seeds was recorded. On the other hand, In this experiment, it was concluded that seed priming with KCl and NaCl had been discovered to be better treatment, especially in the high concentration of salts as compared to non-primed seeds in case of turnip for rising the seeds vigor and seedling growth under salt-stressed conditions. [ABSTRACT FROM AUTHOR]

The research was conducted at the "El Jaguey" belonging to the Cooperative Credit and Service "Ramón López Peña" of the Council Popular Cortés, Sandino, Pinar de Río, with the aim of determining vegetative and yield development in five cultivars of onion (Allium cepa L.). The established cultivars were 'Caribe 71', 'Diandra F1', 'Regent F1', 'Red Creole' and 'Texas Early Grain E 502', which were distributed in a completely randomized block design with three replications. The planting was carried out in rows, at a distance of 0.30 x 0.10 m, with homogeneous seedlings of each cultivar. Evaluations were carried out at 32 and 60 days after transplantation, where the variables plant height, number of active leaves, diameter of the false stem and total fresh mass were characterized. At harvest time, the fresh mass, the equatorial and polar diameters and the humidity were determined in the bulbs. The crop yield was also estimated. The results showed greater vegetative development in the cultivars 'Texas Early Grano E 502' and 'Red Creole', although the former reached yields above 35 t ha-1 and significantly exceeded the other cultivars. The equatorial diameter of the bulb determined its fresh mass in more than 85%, with the exception of the cultivar 'Texas Early Grano E 502', while the percentage of humidity of the bulb exceeded 75% in all cases and was infiuenced by the color of the same. [ABSTRACT FROM AUTHOR]

Introduction: In Mexico, chickpea cultivation takes place during the Fall-Winter cycle, and sometimes is damaged by low temperatures. Both, white "kabuli" type and brown chickpeas, "desi" type, are grown in the Bajio region. Method: Nine "desi" chickpea genotypes were exposed in two trials to low temperatures at two stages of development, germination and vegetative. Four of them were local varieties and five introduced genotypes from ICRISAT, India. In the first trial, the seed of the genotypes was germinated in boxes with sterile sand under two temperatures: 7.0 and 25 o C. The days to emergence were determined and afterwards the seedlings were measured, dried, and weighed. The second test consisted of exposing plants in stage of 7 to 8 compound leaves to a temperature of -4 o C for 60 minutes, with pre and post treatment of 20 min at 4 o C, subsequently they were placed under the sun for two hours; after this protocol, the damage to each individual plant was visually rated. Results: In the first trial, at 25 o C all genotypes germinated in five days (average germination 91.3 %), while at 7.0 o C germination was delayed until 20 days (average germination 80 %) and the percentage decreased differentially among genotypes. ICC 3287, an introduced material, showed the highest average germination under both temperatures 94.9 %, followed by the local cultivar Lerma 89.3 %. The plantlet and root lengths showed significant differences (p < 0.001) between temperature treatments, genotypes, and their interaction; low temperature decreased both characteristics. In contrast, dry weight was similar between temperatures, with significant differences (p < 0.001) among genotypes and for the interaction temperature by genotype. At both temperatures, ICC 1263 showed the highest dry weight followed by cultivar Lerma. In the second trial, ICC 6671 and Lerma show the least damage by low temperature at the vegetative stage. Conclusion: Three introduced genotypes and a local cultivar showed outstanding traits: ICC 3287 higher germination under both tested temperatures, ICC 1263 higher seedling dry weight at suboptimal temperature; ICC 6671 along with cultivar Lerma were tolerant to freezing temperature stress in the vegetative stage. [ABSTRACT FROM AUTHOR]

Mahogany (Swietenia macrophylla King) requires nutrients for the plants to present good quality during their growth in a nursery. The objective of the present study was to evaluate the response to foliar extracts of Ricinus communis L., Solanum torvum Sw. and fruits of Solanum mammosum L. in mahogany seedlings. The hypothesis was that these extracts improve the quality of the seedlings. The experimental design was completely randomized, with four treatments: 1) R. communis L., 2) S. torvum Sw., 3) S. mammosum L., and T4) control without vegetable extracts, and four replications of 45 experimental units. The variables evaluated were morphological (rates of growth in height and stem diameter, and length and number of roots) and of quality (dry weight, robustness index and Dickson quality index). The data were analyzed through one-way ANOVA and the means were compared with the Tukey test (p£0.05). The treatments were applied to the seedlings at 15 d of emergence and the extracts were applied to the foliar surfaces every 15 d, with a dose of 60 mL 20 L-1 of each extract. The units were measured every 15 d, during 60 d. The application of the extracts produced growth rates and dry weights 38% higher with respect to the controls. The extract of R. communis obtained the highest rates and the best Dickson quality index (0.28). Therefore, the extract of this species was the best alternative for improving growth and quality of the mahogany seedlings in the nursery. [ABSTRACT FROM AUTHOR]