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Dry bean landraces could be cultivated under Low-Input (LI) farming conditions because of their yield stability and quality traits. The objective of this research was to evaluate and identify landraces with high yield and stable performance under LI environment and study the relationships among agronomical, physiochemical, and quality traits. Seven landraces of common bean (Phaseolus vulgaris L.) were evaluated in field trials under certified organic management during three consecutive growing seasons (2008-2010) at two different areas located in northern Greece in a RCBD with four replicates. Site per year was considered as one environment. A ranking of landraces according to seed yield potential indicated a group of five high yielding landraces, while Genetic Coefficient of Variation (GCV) for seed yield (9.80%) and number of pods/plant (9.57%) indicated useful genetic variability within landraces, combined with high heritability values (H2= 0.71 and 0.95, respectively). GGE biplot analysis for yield performance and stability indicated that landrace Kastoria fell within the scope of an ideal genotype, followed by three other promising landraces. Significant positive correlation was detected between cooking time and Ash (0.94**). High GCV values for hydration increase (16.77%) and cooking time (15.65%) combined with their high heritability (H2= 0.98 and 0.89, respectively) are of great interest for further genetic advancement. These results indicate that dry bean landraces may provide the appropriate differentiation in several important traits when cultivated under LI conditions, so, effort should be directed to exploit this variability for the development of new varieties suitable for LI agriculture. [ABSTRACT FROM AUTHOR]

Drought affects common bean productivity, and the severity of its impact is expected to increase due to climate change. The use of versatile genotypes could contribute to securing future bean production. This study investigates the adaptability of 10 common bean genotypes of indeterminate growth type under water scarcity conditions by measuring agronomic and physiological parameters. The evaluation occurs under irrigation treatments applied at two different phenological stages (anthesis (WDA) and seed filling initiation (WDSF)). The recorded adaptabilities of the genotypes (G) showed that G10 produced the highest overall seed yield in the normal irrigation (NI) (197.22 g plant -1 ) and WDA (192.78 g plant -1 ), while the G6 had the highest yield at WDSF (196.71 g plant -1 ). For the genotype's average mean, chlorophyll content decreased by 10.5% under drought at WDSF. Net photosynthetic rate ( P n ), stomatal conductance ( g s ), and transpiration rate (E) were reduced at WDA by 53%, 80.8%, and 61.4% and at WDSF by 43.75%, 57.7%, and 36%, respectively, while relative water content (RWC) reduced by 16.48%, on average, for both stages. G10 and G6 showed adaptability when water scarcity occurred at an early (WDA) or later stage (WDSF), respectively, providing insights into using germplasm resources to cope with the drought effect.

High temperatures and water-deficit stress limit cotton production around the world. Their individual effects on plant physiology and metabolism have been extensively studied, however, their combination has received considerably less attention. To that end, growth chamber experiments were conducted using cotton (Gossypium hirsutum L.) cultivar ST5288B2F and the objectives were to discern physiological and metabolic alterations after heat and water stress application (single or combined) and recovery, during cotton's vegetative stage. Under water stress conditions, leaf physiological parameters were suppressed and changes in carbohydrate levels, due to alterations in sucrose-metabolizing enzymes activities, were observed. Heat stress alone increased carbohydrate content, and activities of sucrose-degrading enzymes, while leaf physiology remained unaffected. The combined stress did exacerbate decreases in leaf water potential and soluble acid invertase activity, but the rest of the responses were similar to those of water stress. After stress alleviation, leaf physiological parameters of water-stressed plants did not manage to recover and substantial decreases were observed in leaf starch levels and activities of sucrose-cleaving enzymes, while the majority of parameters of heat-shocked plants returned to control levels. Recovery of the plants subjected to the combined stress was comparable to that of water-stressed plants, but significant differences were observed in carbohydrate levels and sucrose synthase activity. Our study demonstrated that under combined stress and post-stress conditions, water stress was the dominant factor affecting cotton leaf physiology and sucrose metabolism, highlighting however, the unique responses of some traits that could not be deduced from the additive effects of the single stresses., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2020 Elsevier Masson SAS. All rights reserved.)