Leslie Alondra Serrano Gómez

Malting barley grown in arid regions faces constraints related to water and heat stress, as well as mechanical damage caused by wind, all of which affect yield and grain quality. The objective of this study was to characterize agronomic performance, yield components, leaf eco-physiological indicators, and grain biochemical composition in eight two-row malting barley lines (CEMEXICA series) cultivated under arid conditions in the Mexicali Valley. Plant height, spike morphological traits, biomass, yield, thousand-kernel weight, and biochemical variables (starch, protein, fiber, and moisture) were evaluated. In addition, leaf eco-physiological indicators were measured, including stomatal conductance, NBI, total chlorophyll, SPAD, and NDVI. The results showed significant variability among lines, with CEMEXICA-18, CEMEXICA-20, and CEMEXICA-10 standing out for higher yield (up to 8.1 t ha⁻¹) and favorable values for thousand-kernel weight and number of grains per spike. Eco-physiological indices enabled the differentiation of functional strategies among genotypes, particularly NBI and SPAD, whereas NDVI showed lower sensitivity. Regarding grain composition, CEMEXICA-20 and CEMEXICA-18 exhibited the best combination of starch content and protein levels, which are critical attributes for malting quality. Overall, the results indicate that integrating morphological, physiological, and biochemical traits allows the identification of lines with high potential for malt production in arid zones, highlighting the relevance of multi-trait selection for high-stress environments.

Habanero pepper (Capsicum chinense Jacq.) is a high-value crop in Mexico, whose production is limited by water deficit and salinity, particularly in arid regions such as the Mexicali Valley. The objective of this study was to compare methods for quantifying photosynthetic pigments and to evaluate the physiological response of C. chinense to prolonged water stress. Two extraction methods for chlorophylls and carotenoids were evaluated using UV-Vis spectroscopy, along with measurements of relative water content (RWC) and the normalized difference vegetation index (NDVI) with GreenSeeker™, under a completely randomized design with two irrigation treatments. Results showed that, from day 21 onward, water stress significantly reduced chlorophyll a and NDVI, while carotenoids remained stable. RWC remained unchanged for three weeks, reflecting mechanisms of osmotic adjustment and water retention. The leaf disc-based method reduced extraction time by 80% and exhibited lower data dispersion. It is concluded that C. chinense displays tolerance to water deficit for up to 28 days under saline conditions, and that the integration of destructive and non-destructive methods constitutes a robust strategy to assess the impact of water stress on economically important crops.

Agriculture in arid and semi-arid regions faces edaphic and thermal conditions that can limit crop development, yield, and quality. In this context, zinc (Zn) priming is proposed as a strategy to improve the physiological and agronomic performance of crops under adverse edaphic conditions. The present study evaluated the effect of Zn priming on crop establishment, vegetative development, photosynthetic traits, spike formation, yield components, and grain quality. Two treatments, Zn priming and hydropriming with water as the control, were evaluated in a completely randomized design with four replicates per treatment. Evaluations were performed at four phenological stages (BBCH 51, 73, 83, and 89). Plants derived from Zn-primed seeds exhibited greater early vigor, more uniform tillering, and a homogeneous canopy structure. Compared with the control, Zn priming increased the number of grains per spike by 27.7%, 1,000-grain weight by 7.3%, and grain yield by 27.8%. At BBCH 89, NDVI was 35% higher in plants derived from Zn-primed seeds. In addition, these plants reached physiological maturity approximately one week earlier than the control. Proximate analysis showed higher protein content and lower moisture content in grain from the Zn treatment. Overall, the results indicate that Zn priming may represent an agronomic alternative to improve productivity and grain quality in agricultural systems established in arid environments with saline clay soils.

Purple totomoxtle (maize husk) in native maize represents a phenotypic trait of cultural and agronomic significance within traditional Mesoamerican agroecosystems. This study evaluated the phenotypic expression of anthocyanins in vegetative and reproductive tissues of ten native maize genotypes, including inter-parental crosses derived from both pigmented and non-pigmented lines. Field trials were conducted under rainfed conditions in Chiapas, Mexico. Visual and quantitative assessments included pigmentation intensity, chlorophyll and carotenoid content, ear traits and appearance, grain health, and yield performance. Genotypes exhibiting the purple phenotype showed consistent pigment accumulation in stems, nodes, leaf sheaths, tassels, and bracts (totomoxtle), with statistically significant differences compared to non-pigmented controls. Anthocyanin content in totomoxtle increased by 30% during late developmental stages, whereas chlorophyll and carotenoid levels peaked during early vegetative growth. Pigmented materials displayed healthier grain, enhanced ear appearance, and higher yields, with the JCTM × LLMJ cross reaching 6.60 t ha⁻¹. These findings highlight the functional value of purple totomoxtle and its potential in agroecological programs aimed at resilience, genetic conservation, and integral resource utilization, providing useful criteria such as stable pigment expression and superior yield to guide sustainable reproduction strategies.

El cultivo de huertos familiares es una práctica crucial para la producción de alimentos frescos y de calidad, con un énfasis en la agricultura de traspatio en México. Los residuos vegetales generados durante la producción y consumo de las hortalizas pueden tener un alto contenido nutricional y ofrecer oportunidades para su uso eficiente como la alimentación animal o producción de biofertilizantes. Este estudio aborda la evaluación de nutrimentos en la rizósfera de tres cultivos clave: brócoli, repollo y betabel y analizar la distribución de Fe y Mg en órganos vegetales. El estudio se realizó en Suchiapa, Chiapas. El análisis de suelo se realizó con un equipo multiparamétrico de suelo modelo GEMHO-TY (China) antes del trasplante y a 60 días después se determinó el contenido de nitrógeno (N), fósforo (P), potasio (K), pH, conductividad eléctrica y temperatura. Se establecieron camellones de 20 m de largo, 0.4 m de ancho y 0.25 m de alto, se colocó riego por goteo. En la etapa de madurez fisiológica se determinaron condiciones del suelo y el análisis nutricional de las especies por ICP-OES. El análisis del suelo reveló variaciones significativas en la temperatura y la conductividad eléctrica, así como la identificación de etapa crítica para la fertilización con NPK. Además, por gramo de materia seca, se encontró en las hojas de betabel un alto contenido de magnesio (12.81 mg g-1), así como un alto contenido de hierro (2.2 mg g-1) en las raíces del brócoli y el repollo, lo que resalta su potencial como fuente de nutrimentos.

El uso de metanosulfonato de etilo (EMS) es una tecnología utilizada para aumentar la variabilidad genética de cultivares. En el mejoramiento genético del cafeto, EMS podría generar nuevos rasgos fenotípicos y bioquímicos de importancia agrícola. El objetivo de la presente investigación fue determinar los cambios en la morfología y producción de metabolitos secundarios en plantas de cafeto generadas a partir de líneas celulares tratadas con EMS. Callos de Coffea arabica cv., Borbón fueron expuestos a nueve concentraciones de EMS, posteriormente, se determinó el porcentaje de supervivencia y la biomasa fresca. Se regeneraron plantas en medio MS suplementado con vitaminas, antioxidantes y 6-bencilaminopurina. A las 20 semanas se registraron cambios morfológicos observados con respecto a los callos no tratados con EMS. Empleando hojas secas se hizo la extracción de metabolitos secundarios, la cuantificación se realizó mediante cromatografía líquida de alta resolución. La supervivencia y crecimiento del callo disminuyó con el aumento de la concentración de EMS (dosis letal media: 148.8 mM), en plántulas generó cambios en la morfología de la hoja, enanismo y la formación de tres meristemas, que aumentarían el número de hojas. Finalmente, 140 mM de EMS incrementó el contenido de cafeína, ácido cafeico y ácido clorogénico.