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Objective: To analyze the race diversity and geographic distribution of the native maize landraces currently cropped at southern Nuevo León, México. Design/Methodology/Approach: Data was obtained from 41 accessions which represent the commercial production in the dry land area, where fertilization and pest control are scarcely used. Landraces were classified according to the CONABIO guidelines for ear traits. Results: The measured accessions correspond to seven maize races and to seven interracial crosses. The two most frequent maize races were Ratón and Cónico Norteño, mainly located in the dry areas with less rain. Study Limitations/Implications: Three races, Celaya, Tablilla de Ocho and Elotes Cónicos, had not been previously reported; while two formerly reported races Tabloncillo and Olotillo, were no longer found. This study did not include the grain-colored accessions. Findings/Conclusions: Three collections stood out for producing large cobs with large kernels, thus showing a high yield potential. The maize landraces harvested in dryland areas might offer advantages to be grown under harsh environments or be used as gene donors for drought tolerance. [ABSTRACT FROM AUTHOR]

Copyright of Farmacia is the property of Societatea de Stiinte Farmaceutice Romania 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.)

The effects of suspensions of zinc oxide nanoparticles at concentrations between 100 and 500 mg L−1 on germination of Capsicum chinense seeds and vigor of plants were evaluated using a randomized complete design with four replications, resulting in increased germination and improved development of lengths of plumule and radicle. The activities of peroxidase, catalase and ascorbate peroxidase were determined, showing that at all concentrations the activities of the former two enzymes were increased, whereas the activity of the latter was reduced at 500 mg L−1. Pretreatments of seeds with ZnO nanoparticles can improve germination and development of seedlings and the activities of antioxidant enzymes. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing 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.)

In México, around 82% of the total production of maize is grown under rainfed conditions leading to a water stress environment which affects physiologic and biochemical process of the plant. Maize bran is a composited plant material consisting mainly in aleurone layer, testa and pericarp; the cell walls of these tissues are composed of proteins, non-starch polysaccharides, phenolic acids and lignin which are potential bioactive substances for human nutrition. In this research it was investigated the effect of water stress on cell wall components in the bran of three genotypes of maize by applying irrigation and water stress treatments. The content of protein, lignin, arabinoxylans, total phenols and phenolic acids was performed in the bran of 'Cebú', 'DK2027' and 'DK2034' genotypes. Water stress applied through grain development stage increased protein levels of 'Cebú', 'DK2027' and 'DK2034' in 4.05, 16.13 and 0.40% respectively. Respecting to lignin content, water stress increased levels at 1.28, 2.26 and 4.24% for 'Cebú', 'DK2027' and 'DK2034', respectively. Arabinoxylans content also increased in water stress treatment at levels of 1.28, 2.26 and 3.66% in 'Cebú', 'DK2027' and 'DK2034'. On the other hand, water stress treatment decreased the levels of total phenols and hydroxycinnamic acids in the three maize hybrids analysed. Reduction of total phenols was 35.34, 5.59 and 31.57% for 'Cebú', 'DK2027' and 'DK2034', respectively. In addition, the levels of t-ferulic, c-ferulic and p-coumaric acids decreased 17.74, 23.93, 29.83% in 'Cebú', 8.92, 8.62, 24.03% in 'DK2027' and 13.66, 11.03, 10.38% in 'DK2034' respectively. [ABSTRACT FROM AUTHOR]

Jatropha curcas is a species with a biodiesel production potential. The supply of elite planting material is critical due to traditional spread disadvantages. Plant tissue culture is an alternative to obtain quality plant material for planting. For these reasons, the objective of this study was to evaluate the feasibility of three phenological ages of petioles (1st, 2nd and 3rd node), and the effect of polyvinylpyrrolidone (PVP) on explants viability of the INI-3 and INI-6 genotypes of J. curcas and the petioles morphogenetic expression of the INI-6 genotype in two culture media (Yasuda and MS) with different doses of TDZ, BA and AIB. The in vitro establishment evaluated the PVP of the INI-3 and INI-6 genotypes with a completely randomized design (CRD) in a 2x2 factorial arrangement and 90 repetitions per treatment. The evaluated variables were viability and callus presence; viability was assessed with the Chi-square test (X2) and the callus weight by an ANOVA. During the induction stage, two media culture added with TDZ, BA and AIB were evaluated in the INI-6 genotype due to their increased viability, in a DCA with a 2x2x2x3 factorial arrangement. Three replications, where the evaluated variable was the callus presence, using a logistic regression analysis (LRA). The results show that the viability is independent from the genotype, according to the X2 value (p=0.700), but dependent of the petiole type (p=0.019) and PVP addition (p = 0.001). The presence and callus production were influenced by the genotype expressed in the X2 and callus weight by an ANOVA. The induction stage showed that the AIB and TDZ are related to the callus presence based on the LRA. [ABSTRACT FROM AUTHOR]

Mexico, the center of origin of maize (Zea mays L.), has taken actions to preserve the identity and diversity of maize landraces and wild relatives. Historically, spatial isolation has been used in seed production to maintain seed purity. Spatial isolation can also be a key component for a strategy to minimize pollen-mediated gene flow in Mexico between transgenic maize and sexually compatible plants of maize conventional hybrids, landraces, and wild relatives. The objective of this research was to generate field maize-to-maize outcrossing data to help guide coexistence discussions in Mexico. In this study, outcrossing rates were determined and modeled from eight locations in six northern states, which represent the most economically important areas for the cultivation of hybrid maize in Mexico. At each site, pollen source plots were planted with a yellow-kernel maize hybrid and surrounded by plots with a white-kernel conventional maize hybrid (pollen recipient) of the same maturity. Outcrossing rates were then quantified by assessing the number of yellow kernels harvested from white-kernel hybrid plots. The highest outcrossing values were observed near the pollen source (12.9% at 1 m distance). The outcrossing levels declined sharply to 4.6, 2.7, 1.4, 1.0, 0.9, 0.5, and 0.5% as the distance from the pollen source increased to 2, 4, 8, 12, 16, 20, and 25 m, respectively. At distances beyond 20 m outcrossing values at all locations were below 1%. These trends are consistent with studies conducted in other world regions. The results suggest that coexistence measures that have been implemented in other geographies, such as spatial isolation, would be successful in Mexico to minimize transgenic maize pollen flow to conventional maize hybrids, landraces and wild relatives. [ABSTRACT FROM AUTHOR]

Chromatic, phenolic and antioxidant properties were evaluated in ten sorghum genotypes grown in Nuevo León, México. Lightness, Chroma and hue angle ranged from 64 to 83, 12 to 20 and 61 to 82 respectively, indicating that colour of the samples were located in the gray orange-yellow zone of the hue circle. Based on these results, samples were classified in three colour groups being Very Soft Orange, Slightly Desaturated Orange and Grayish Orange. Results in phenolics ranged from 796 to 15,949, 175 to 12,674 and 193 to 25,780 μgCE g-1 in total phenolics by Folin-Ciocalteu, total flavonoids by Aluminum Chloride and condensed tannins by Vanillin-HCl respectively. On the other hand, antioxidant capacity ranged from 1.20 to 93.83, 30.25 to 156.08 and 2.62 to 98.50 μ g-1 in 2,2-diphenyl-1-picrylhydrazyl, 3-ethyl-benzothiazoline-6-sulfonic acid and Ferric Reducing Antioxidant Power respectively. Significant differences (pE0.05) were observed in statistical analysis for both individual and group colour samples in chromatic, phenolics and antioxidant activity evaluations, showing 'Rox Orange' genotype and Grayish Orange colour group the highest levels. [ABSTRACT FROM AUTHOR]

Copyright of Revista Colombiana de Entomologia is the property of Universidad del Valle 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.)

Highlights: [•] High pressure processing (HPP) can be a postharvest treatment on fresh fruits. [•] The mango ‘Keitt’ treated with HPP retains its capability to ripen. [•] Some physiological changes in mango ‘Keitt’ take place immediately after HPP. [•] HPP-treated mango ‘Keitt’ show physiologic changes during postharvest ripening. [ABSTRACT FROM AUTHOR]

Charcoal rot ( Macrophomina phaseolina) is a major disease of beans ( Phaseolus vulgaris L.) in Mexico. The use of germplasm combining high-yield stability with resistance to drought and charcoal rot could reduce damage from this disease. In this study, we compared the Eberhart and Russell method and the Additive Main Effect and Multiplicative Interaction (AMMI) model plus biplot analysis for measuring grain yield (GY) and charcoal rot resistance (CHRR) stabilities in 98 F8 : 10 recombinant inbred lines (RILs) derived from a cross between bean adapted to the tropics (BAT) 477 (resistant) × Pinto UI-114 (susceptible). Experiments were conducted from 2007 to 2009 in Isla, Cotaxtla, Río Bravo and Díaz Ordaz, México, under irrigated or terminal drought conditions. anova detected significant differences (P ≤ 0.05) in GY and CHRR among environments, genotypes and genotype × environment interactions (GEI). Most RILs showed good responses to unfavourable environments based on GY (48) and CHRR (40). AMMI anova s for both traits showed that all sources of variation in the model accounted for approximately 49% of the total squared sum. For the first principal component (PC1), we found 13 RILs that were stable for GY, and for the second (PC2), we found 9 that were stable for GI. For CHRR, we detected 14 stable RILs (PC1) and eight (PC2). Biplot analysis showed the largest vectors for Díaz Ordaz (irrigated and drought, 2008), where the highest and most variable GYs were detected. The shortest vectors were found in Isla (drought, 2007) and Río Bravo (irrigated and drought, 2008), where the lowest and least variable GY were found. We found differential responses of RILs to locations, years and soil humidity conditions as well as significant GEI based on GY and CHRR. The two methods were complementary, and both gave us information to select stable, high-yield germplasm associated with resistance to charcoal rot disease. [ABSTRACT FROM AUTHOR]

Sorghum (Sorghum bicolor (L.) Moench) is cultivated in regions with frequent drought periods and high temperatures, conditions that have intensified in the last decades. One of the most important photosynthetic components, sensible to hydric stress, is maximum quantum yield for photosystem II (PSII, or Fv/Fm). The objective of the present study was to identify sorghum genotypes with tolerance to hydric and heat stress. The treatments were hydric status (hydric stress or non-hydric stress (irrigation)), the plant's developmental stages (pre or post-anthesis), and six genotypes. The response variables were Fv/Fm; photosynthetic rate (PN); stomatal conductance (gs); transpiration rate (E); relative water content (RWC); damage to cell membrane (DCM) at temperatures of 40 and 45 °C; and agronomic variables. The experiment was conducted in pots in open sky in Marín, N.L., in the dry and hot northeast Mexico. The treatment design was a split–split plot design, with three factors. Hydric stress diminished the functioning of the photosynthetic apparatus by 63%, due to damage caused to PSII. Pre-anthesis was the most vulnerable stage to hydric stress as it decreased the weight of grains per panicle (85%), number of grains per panicle (69%), and weight of 100 grains (46%). Genotypes LER 1 and LER 2 were identified as tolerant to hydric stress, as they had lower damage to PSII; LER 1 and LEB 2 for their superior RWC; and LER 1 as a thermo tolerant genotype, due to its lower DCM at 45 °C. It was concluded that LER 1 could have the potential for both hydric and heat stress tolerance in the arid northeast Mexico. [ABSTRACT FROM AUTHOR]

Maize is the most important crop around the world and it is highly sensitive to abiotic stress caused by drought, excessive salinity, and extreme temperature. In plants, trehalose has been widely studied for its role in plant adaptation to different abiotic stresses such as drought, high and low temperature, and osmotic stress. Thus, the aim of this work was to clone and characterize at molecular level the trehalose-6-phosphate synthase (TPS) and trehalose-6-phosphate phosphatase (TPP) genes from maize and to evaluate its differential expression in maize seedlings under drought stress. To carry out this, resistant and susceptible maize lines were subjected to drought stress during 72 h. Two full-length cDNAs of TPS and one of TPP were cloned and sequenced. Then, TPS and TPP amino acid sequences were aligned with their homologs from different species, showing highly conserved domains and the same catalytic sites. Relative expression of both genes was evaluated by RT-qPCR at different time points. The expression pattern showed significant induction after 0.5 h in resistant lines and after two to four hours in susceptible plants, showing their participation in drought stress response. [ABSTRACT FROM AUTHOR]

The physiological responses of habanero pepper plants (Capsicum chinense Jacq.) to foliar applications of zinc sulphate and zinc nano-fertilizer were evaluated in greenhouse trials. The effect of the supplement on fruit quality of habanero pepper was particularly observed. Habanero pepper plants were grown to maturity, and during the main stages of phenological development, they were treated with foliar applications of Zn at concentrations of 1000 and 2000 mg L−1 in the form of zinc sulfate (ZnSO4) and zinc oxide nanoparticles (ZnO NPs). Additional Zn was not supplied to the control treatment plants. ZnO NPs at a concentration of 1000 mg L−1 positively affected plant height, stem diameter, and chlorophyll content, and increased fruit yield and biomass accumulation compared to control and ZnSO4 treatments. ZnO NPs at 2000 mg L−1 negatively affected plant growth but significantly increased fruit quality, capsaicin content by 19.3%, dihydrocapsaicin by 10.9%, and Scoville Heat Units by 16.4%. In addition, at 2000 ZnO NPs mg L−1 also increased content of total phenols and total flavonoids (soluble + bound) in fruits (14.50% and 26.9%, respectively), which resulted in higher antioxidant capacity in ABTS (2,2′azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)), DPPH (2,2-diphenyl-1-picrylhydrazyl), and FRAP (ferric reducing antioxidant power) (15.4%, 31.8%, and 20.5%, respectively). These results indicate that application of ZnO NPs could be employed in habanero pepper production to improve yield, quality, and nutraceutical properties of fruits. [ABSTRACT FROM AUTHOR]

The growing global demand for energy and the reduction of energy based on oil are driving the search for new sources of energy that are environmentally friendly. To achieve this goal, it is also necessary to optimize the related processes. In this study, the behavior of the agronomic parameters of, and the energy invested in, production systems based on a new variety of sweet sorghum (Sorghum bicolor (L.) Moench) called ROGER were determined to define the optimal production conditions. To this end, three methods of tillage (minimum, traditional, and traditional tillage with rupture of the plow layer) and three types of fertilizers (inorganic, organic, and without fertilizer) were established, and to estimate the energy efficiency, the inputs and the energy outputs of each system were considered. The traditional tillage with breaking of the plow layer and the organic fertilizer showed the highest values of plant height (2.45 and 2.39 m, respectively); total fresh weight of the plant (51.66 and 50.77 t·ha−1, respectively), of the stem (42.7 and 41.05 t·ha−1, respectively), and of the juice (21.89 and 22.57 t·ha−1, respectively); the volume of the juice (20,783.12 and 22,529.59 L·ha−1, respectively); and Brix degrees (16.04% and 15.01%, respectively). However, the highest energy efficiency was registered in the production system that used the minimum tillage, with a value of 15.11, as well as when no fertilizer was applied with 18.68. [ABSTRACT FROM AUTHOR]

The effects of zinc oxide nanoparticles on seed germination and seedling growth of Capsicum annuum L. were determined in this research. Total phenols content, total flavonoids, and condensed tannins, as well as 2,2-diphenyl-1-picrylhydrazyl (DPPH) antioxidant capacity was determined. Results indicated that treatment with zinc oxide nanoparticles (ZnO-NPs) improved seed germination rate during the first seven days. The seed vigor germination increased 123.50%, 129.40% and 94.17% by treatment with ZnO-NPs suspensions at 100, 200 and 500 ppm, respectively. The morphological parameters tested revealed that ZnO-NPs treatments did not significantly affect plumule development, but they had a significant impact (p ≤ 0.01) on radicle length. Suspensions at 100, 200 and 500 ppm of ZnO-NPs inhibited seedling radicle growth and promoted accumulation of phenolic compounds, with a phytotoxic effect in this organ. Results suggested that zinc oxide nanoparticles influence seed vigor and seedling development and promoted the accumulation of desirable phenolic compounds in the radicle. [ABSTRACT FROM AUTHOR]

Sweet sorghum (Sorghum bicolor [L.] Moench) is a crop that is well known for its high production of biomass and sugars in the stem juice. The objective of this work was to evaluate the productivity of sweet sorghum 'Roger' based on the dynamics of sugar production and dry biomass by considering different production methods and plant phenological stages. The experimental design consisted of different tillage and fertilization methods established in a randomized complete block design with a split plot arrangement. Tillage treatments were assigned to the plot using the three levels of minimum tillage, traditional tillage, and traditional tillage that included a subsoil operation. Fertilization treatments were assigned to the subplot using the three levels of organic fertilizer, inorganic fertilizer, and without fertilizer. Data collection was performed at different plant phenological stages from anthesis to physiological maturity. Results showed that evaluated agronomic parameters depended on the phenological stage (P < 0.05) rather than the production methods (P > 0.05). Thus, the distribution and accumulation of sugar by stem internodes was associated with plant phenological components. The highest values of the concentration of total soluble solids (14.89%), juice sugar content (22.91 g), juice sugar concentration (527.46 mg g-1 DW), dry biomass (60.04%), and dry biomass yield (19.01 t ha-1) were observed at the physiological maturity stage of the plant. [ABSTRACT FROM AUTHOR]