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Background: Chiapas and Veracruz are the main producing states in the lowlands of southeastern Mexico, with a total harvested volume of 90,146 t of grain in 2020, in a joint planting area of 151,037 ha. However, the cultivation of this legume is subject to a series of biological, climatic and edaphic problems, which make the average yields notoriously low. The objective of this study was to identify high-yielding black bean lines, resistant to diseases and with better adaptation than three commercial cultivars currently used in both entities. Methods: During 2019 and 2020, in seven environments of Veracruz and Chiapas, 11 lines and the cultivars Negro Jamapa, Negro Medellín and Verdín were evaluated. An analysis of variance of the variables was performed by each environment and combined analysis of the incidence of BGYMV and grain yield. Result: Jamapa Plus/XRAV-187-3-4-4 was the most productive line, with an average yield of 1,542 kg ha-1, statistically similar to that of Jamapa Plus/XRAV-187-3-1-2 and higher than that of the rest of the genotypes. Both lines showed resistance to web blight and rust and low incidence of BGYMV, diseases that significantly reduced grain yield. Jamapa Plus/XRAV-187-3-1-2 showed stability throughout the evaluation environments. [ABSTRACT FROM AUTHOR]

Synthetic maize varieties present advantages in adaptability, they can be used for several planting seasons, without affecting the yield and is easier the seed production. Thus, with the main objective of knowing the yield and agronomic traits of synthetic maize varieties for the tropic, during 2013 to 2018 there was conducted an experiment in Cotaxtla and Carlos A. Carrillo in Veracruz and Huimanguillo in Tabasco state locations. The experiment was distributed in complete blocks at random design with 21 entries and three replications in plots of two rows 5m long and 62,500 pl ha-1. The agronomic traits were: Grain yield, days to tassel and silking, plant and ear aspect and sanity, lodging, bad husk cover and ear rot. From the combined analysis for yield, there was found high significant differences for Varieties (V), For environments (E), and for the interaction VxE, and a coefficient of variation of 16.20%. The Carlos A. Carrillo, Ver., location in 2016B, recorded the highest yield with 6.94 t ha-1. The best five synthetics at 0.05 of probability were: VS-536, Synthetic 2B, Synthetic 5B, Synthetic 2C and Synthetic 11C. [ABSTRACT FROM AUTHOR]

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The manzano or cera chilli pepper (Capsicum pubescens) is a perennial plant native from the highlands of South America. During storage, the main problem is its hardnes of head, which causes a decrease in germination under natural conditions. Because there is little information on germination, it is necessary to implement alternatives that guarantee the resource within a breeding program. The aim was to evaluate the effect of sulfuric acid (H2SO4), hydrogen peroxide (H2O2) and gibberellic acid-3 (C19H22O6) on the percentage of emergence and characteristics of C. pubescens seedlings. The experiment was carried out in the Unit of Management and Conservation of Genetic Resources of the Faculty of Biological and Agricultural Sciences of the Universidad Veracruzana. C. pubescens seeds from the Huatusco, Veracruz, Mexico, stored at room temperature for one year were used. The treatments studied were immersion in H2SO4 (100, 75, 60%, 30 min); immersion in H2O2 (20, 10, 15%, 15 min), immersion in C19H22O6 (25, 20, 15 mg, 24 h) and the control treatment. The results in the present study reveal significant statistical differences (P < 0.01) for all the variables evaluated. The best percentage of germination was caused by immersion in C19H22O6 (15 mg, 24 h) and H2O2 (20%, 15 min). The treatment with H2SO4 was harmful since there was no emergency. [ABSTRACT FROM AUTHOR]

The tomato (Solanum lycopersicum) is one of the main horticultural crops in the world because of the important economic benefits that its commercialization generates. Even though the species is widely cultivated in the world, it is susceptible to pests, diseases, and environmental stresses due to the loss of its genetic diversity. There is a wild form called S. l. var ceraciforme that is distributed from South America (its center of origin) to Mexico (its area of domestication), specifically on the slope of the Gulf of Mexico in Veracruz. Due to the large genetic diversity of these wild tomatoes, it is important to improve its crop. The objective of this investigation was to identify patterns of environmental diversification of the tomato, infer the processes of adaptation of the populations in the area of domestication with respect to their center of origin and propose measures of conservation and variation of S. l. var. cerasiforme. We generated two ecological niche models (MNE) with Maxent version 3.4.1 (evaluated with AUC and partial-ROC) to determine the suitability of environmental conditions including their respective projections from the domestication center to the area of origin and vice versa. We used eight variables of temperature and precipitation. Additionally, we included tomato records from bibliographical sources and fieldwork. We also used the niche comparison test (equivalency and similarity) proposed by Broennimann et al. (2012) to evaluate the similarity of environmental conditions in both regions. Subsequently, we carried out an analysis of variance followed by a mean comparison test (Tukey, P = 0.05) with all environmental variables measured. The values of AUC (0.93 and 0.80) and partial-ROC (1.86 and 1.71, P = 0.0001) of the MNE showed that they were good predictive models. We observed that, in the center of Mexico, there are environmental conditions similar to those of the center of origin, unlike the slope of the Gulf of Mexico where they are different. The equivalency test showed that the environmental comparison between both regions is less similar than expected by chance (P = 0.003). The similarity test indicated that the existing similarity between both regions can also be obtained by chance (P = 0.683). We also found significant differences in three temperature and precipitation variables. In conclusion, we determined that the center of origin and domestication of S. l. var. cerasiforme has similar environmental characteristics despite the geographic distance; nevertheless, there are geographical zones (the Gulf of Mexico in Veracruz) in the area of domestication with different environmental conditions. Those places have the potential to contain valuable germplasms. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the productivity of maize hybrids developed for The High Valleys of Mexico. Four hybrids in their versions of male-sterile and fertile were evaluated in four uniform experiments using a randomized complete block design, at the Experimental Station of Mexico (CEVAMEX) and the Faculty of Higher Studios Cuautitlan (FESC-UNAM). The statistical analysis was performed in a combined form with the factors: hybrids (4), locations (4), male sterility/fertility versions (2), and the interactions between these factors. Significant differences for genotypes (p≤0.01), for locations and for interaction hybrid x locations (p≤0.05) were detected. The coefficient of variation for seed yield was 21.5% and overall mean was of 6,998 kg/ha. The site CEVAMEX 2009, in its first planting date, produced 8829 kg/ha and surpassed the other three environments. The performance of the four hybrids was similar (p>0.05). The male sterile version had a yield of 7170 kg/ha, similar (p>0.05) to the fertile version (6826 kg/ha), which confirms that the versions of the fertile and male-sterile hybrids of this study are isogenic. [ABSTRACT FROM AUTHOR]