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Aims: Habanero pepper (Capsicum annuum L.) cultivation is growing worldwide, mainly as a result of its high demand and nutritive contribution to human society. The presence of endogenous gibberellins and cytokinins in seeds of various vegetable crops has been related to a good germination; however, little is known on habanero pepper. The aim of this study was to search for the presence, identification and amount of gibberellins and cytokinins in seeds of habanero pepper cv “Jaguar”. Study design: Laboratory analysis for gibberellins and cytokinins were organized in solvent solutions groups with three technical replicates using a complete randomized design and results when applicable were analyzed using the statistical program 'RStudio' (version 10) and data obtained subjected to a comparison of means with the Tukey (P≤0.05) test. Place and duration of study: The experiment was conducted at the Department of Horticulture in Universidad Autónoma Agraria Antonio Narro, Saltillo, Mexico, during 2020-2021. Methodology: Lots of 50 grams dry weight of “Jaguar” habanero pepper seed samples were freeze dried and prepared with several organic solvents for the extraction, purification and identification of gibberellins and cytokinins using the techniques of GC-MS and GCMS-SIM respectively. Results: Gibberellins A1, A4, A7, A9, A15, A17 and A44 were found in habanero seed tissue. The cytokinins zeatin and zeatin-riboside were also detected in analyzed habanero samples.  Conclusion: The endogenous gibberellins A1, A4, A7, A9, A15, A17, A44, and the cytokinins zeatin and zeatin-riboside are present in habanero pepper cv “Jaguar” contributing to an improve seed viability, ensuring health and overall plant yield.

Debido que la agricultura bajo cubiertas plásticas es una alternativa para mejorar la producción de cultivos hortícolas, el objetivo de este estudio fue evaluar el efecto de cuatro tipos de cubiertas de túneles de diferentes materiales y colores en la transmitancia de la radiación y su relación con contenido de clorofila, crecimiento y rendimiento de un cultivo de calabacita (Cucurbita pepo) cv. Zucchini. El estudio se realizó durante el ciclo de producción otoño-invierno 2015 a 2016, en Sabinas Hidalgo, Nuevo León. Los materiales utilizados fueron tres túneles con láminas de policarbonato de color rojo, azul y claro respectivamente, y otro con una cubierta de polietileno de alta densidad. Dentro de cada túnel se registró la radiación solar y la fotosintéticamente activa. También se obtuvo el contenido de clorofila de las hojas de las plantas. Los resultados mostraron que, para la banda de la radiación PAR, el policarbonato de color rojo tuvo la menor transmitancia (23.51%), seguido por el de color azul (57.46%), el polietileno de alta densidad (60.51%) y el de mayor transmitancia fue el policarbonato de color claro (82.57%). Las plantas que crecieron bajo el túnel con el policarbonato de color claro tuvieron mayor contenido de clorofila, mayor desarrollo foliar y rendimiento de fruto. Por el contrario, las plantas en el túnel de policarbonato rojo que recibieron la menor cantidad de radiación PAR, tuvieron el menor contenido de clorofila, menor desarrollo foliar y sin rendimiento de frutos.

Different studies have shown that global warming and climate change have increased the planet's temperature in different locations. For the apple-growing farmers, this may have a negative impact on the accumulations of chill units when the air temperature during the fall-winter season increases. When the entire trees are covered with a reflective material, the wood temperature may decrease. Therefore, the objective of this study was to evaluate the effect of whitening (with calcium hydroxide) the entire apple trees (Malus domestica Borkh) after defoliation, on the branches and trunks' internal temperature (under the bark), the accumulation of chill units (CU), its effects on fruit yield and quality and the relation with the use of thidiazuron (TDZ) (inducer of budbreak). The study was conducted during the fall-winter seasons of 2019-2020 and 2020-2021. The results of this study showed that at the hours of the highest incidence of solar radiation, the internal temperature of the whitened trunks and leaves decreases up to 9˚C and 6˚C respectively. The accumulated CU during the time of the study, of the whitened branches were up to 81% higher than the ones recorded on the branches with no whitening; while the CU was lost at the hours of highest solar radiation (due to a high temperature) were up to 37.2% smaller. Entire tree whitening increased up to 26% of the yield per tree compared to the application of TDZ. No statistical difference in fruit quality was observed between whitened trees and those with no whitening but with the application of thidiazuron.

Aims: Tomato (SolanumlycopersicumL.) is one of the most important vegetable crops worldwide, mainly as a result of its economic and nutritive contribution to human society. The presence of endogenous gibberellins and cytokinins in seeds of several crops has been related to a good germination; however, little is known in tomato. Therefore, the aim of this study was to analyze and identify the presence of gibberellins and cytokinins in saladette tomato seeds. Study Design: Laboratory analysis for gibberellins and cytokinins were conducted in solvent solutions groups with three technical replicates using a complete randomized design and results when applicable were analyzed using the statistical program 'RStudio' (version 10) and data obtained subjected to a comparison of means with the Tukey (P≤0.05) test. Place and Duration of Study: The experiment was conducted at the Department of Horticulture in Universidad AutónomaAgraria Antonio Narro, Saltillo, Mexico, during 2020-2021. Methodology: Lots of 50 grams dry weight of saladette “SVTE8832” tomato seed samples were freeze dried and prepared with several organic solvents for the extraction, purification and identification of gibberellins and cytokinins using the techniques of gas chromatography mass spectrometry(GC-MS) and gas chromatography mass spectrometry with selection ion monitoring(GCMS-SIM) respectively. Results: Gibberellins A1, A4, A7, A9, A12, A15, A17, A20, A44 and A53 were found in tomato seed tissue. The cytokininszeatin and zeatin-ribozide were also detected in analyzed tomato samples. Conclusion:The endogenous gibberellins A1, A4, A7, A9, A12, A15, A17, A20, A44, A53 and the cytokininszeatin and zeatin-riboside are present in saladette“SVTE8832” tomato seeds.