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Drought is one of the major factors limiting global crop yield. In Mexico, agriculture is expected to be severely affected by drought. The Capsicum genus has several crop species of agricultural importance. In this work, we analysed the Capsicum chinense plant physiological responses and differentially expressed genes under water stress mainly focused on the responses elicited following recovery through repetitive stress. Plants were cultivated in an experimental block. Each block consisted of plants under water deficit and a control group without deficit. Morphometric and functional parameters, and the expression of genes related to resistance to abiotic stresses were measured. Morphological differences were observed. Plants subjected to water deficit showed impaired growth. Nonetheless, in the physiological parameters, no differences were observed between treatments. We selected abiotic stress-related genes that include heat-shock proteins (HSPs), heat-shock factors (HSFs), transcription factors related to abiotic stress (MYB, ETR1, and WRKY), and those associated with biotic and abiotic stress responses (Jar1 and Lox2). HSF, HSP, MYB72, ETR1, Jar1, WRKYa, and Lox2 genes were involved in the response to water-deficit stress in C. chinense plants. In conclusion, our work may improve our understanding of the morphological, physiological, and molecular mechanisms underlying hydric stress response in C. chinense. [ABSTRACT FROM AUTHOR]

Despite the proven economic importance of Aloe vera, studies of saline stress and its effects on the biochemistry and mineral content in tissues of this plant are scarce. The objective of this study was to grow Aloe under NaCl stress of 0, 30, 60, 90 and 120 mM and compare: (1) proline, total protein, and enzyme phosphoenolpyruvate carboxylase (PEP-case) in chlorenchyma and parenchyma tissues, and (2) ion content (Na, K, Ca, Mg, Cl, Fe, P. N, Zn, B, Mn, and Cu) in roots, stems, leaves and sprouts. Proline and PEP-case increased as salinity increased in both parenchyma and chlorenchyma, while total protein increased in parenchyma and decreased in chlorenchyma, although at similar salt concentrations total protein was always higher in chlorenchyma. As salinity increased Na and Cl ions increased in roots, stems, leaves, while K decreased only significantly in sprouts. Salinity increases typically caused mineral content in tissue to decrease, or not change significantly. In roots, as salinity increased Mg decreased, while all other minerals failed to show a specific trend. In stems, the mineral concentrations that changed were Fe and P which increased with salinity while Cu decreased. In leaves, Mg, Mn, N, and B decreased with salinity, while Cu increased. In sprouts, the minerals that decreased with increasing salinity were Mg, Mn, and Cu. Zinc did not exhibit a trend in any of the tissues. The increase in protein, proline and PEP-case activity, as well as the absorption and accumulation of cations under moderate NaCl stress caused osmotic adjustment which kept the plant healthy. These results suggest that Aloe may be a viable crop for soil irrigated with hard water or affected by salinity at least at concentrations used in the present study. [ABSTRACT FROM AUTHOR]

Suaeda edulis (Flores Olvera & Noguez) is a halophile species that grows in saline environments, with concomitant difficulties to germinate and reproduce. Once a null germination under a salinity gradient or fresh water was observed, a plant-growth bioregulator (BioR) was applied to interrupt dormancy and improve germination in vitro. This BioR is composed of gibberellins and adjuvant regulators; and 12.5, 25.0, and 37.5 mg L−1 of gibberellins with immersion at 24, 48, and 72 h were assayed. Most of the normality and homoscedasticity tests were favorable, except in three of 24 cases. On the germination percentage (transformed values), the dose 25.0 mg L−1 reflected the highest values of 5.5 and 6.0 units at 48 and 72 h. For the mean germination time, the highest level of 37.5 mg L−1 at 24 h reflected the best response. For the germination rate, the best one was 25 mg L−1 at 48 h, reaching 12% per day, but for the germination speed coefficient, the best value was observed with 25.0 mg L−1 at 24 h. It was concluded that to improve germination of S. edulis seeds, it is necessary to assess a dose-gradient of gibberellins, starting at 25.0 mg L−1, with higher values to break dormancy. [ABSTRACT FROM AUTHOR]

During 2006 and 2007 year were carried out field trial in four locations in Granma province with objective to study drought tolerance of this variety in the region condition. The variety were evaluated with two condition of humidity: irrigation in all vegetative growth and three establishment irrigation and withholdig of this in all vegetative growth (drought). A split plot designs with four replication was used where greather plot belonged to irrigation treatment and a little plot to varieties. With yield obtained between two conditions of irrigation were calculated the intensity and susceptibility drought index, geometrics means and loss yield percentage. The use of this index allowed identifying the tolerance level of variety to drought and its adaptation specific to each humidity conditions. The variety obtained different yield in each location and Amalia and Vyta variety to standed out for its yield in average fruit, and were most stable and suitable to production in location with drought condition. [ABSTRACT FROM AUTHOR]

From November 2006 to February 2007 year, were carried out field experiment in "Las Celias" vegetable garden of Guisa in Granma province with objective to study the effect of drought condition of the region over the yield and its component in four cubaine variety of tomatoe. The variety were evaluated in two condition of humidity: irrigation in all vegetative growth and three establishment irrigation and withholdig of this in all vegetative growth (drought). A split plot designs with four replication was used and the greather plot belonged to irrigation treatment and a little plot to variety. The variety obtained different yield and Amalia and Vyta variety to standed out for its yield in average fruit, and were most suitable to production in location with drought condition. [ABSTRACT FROM AUTHOR]