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Dieback is a physiological disorder that has caused losses on eucalyptus plantations. Thinking that water stress is one of the triggers for the physiological disorder and aiming at the early identification of tolerant genotypes, we evaluated plantlets of four commercial clones with divergent behavior in field conditions. The plantlets were grown in a greenhouse where the drought conditions were provided by the application of polyethylene glycol 6000 solutions at 100 and 300 g L−1. After water deficit treatments, the morphological, physiological, nutritional and metabolic analyses were performed. SuzT maintained the carbon fixation and the instantaneous water use efficiency, even under water deficit, while sustaining growth. This resulted in higher leaf area and total dry mass in SuzT. Despite higher photosynthetic rate, SuzS exhibited reduced dry biomass accumulation, implying less efficient carbon use. SuzT revealed a higher level of calcium that supports cell structure and homeostasis and indicates higher capacity to manage specific resources and survival under water deficit. SuzT suffered reduction in some free amino acids; however, there was no significant variation for total amino acid content. The principal component and cluster analyses indicated that SuzMT and SuzTP genotypes behave similarly to SuzT under water deficit, while SuzS clustered in isolation. Our results support that there are common trends in water deficit responses for contrasting eucalypt genotypes. The existence of other strategies coping with water deficit resistance is not discarded and should be further evaluated. [ABSTRACT FROM AUTHOR]

The aim of this study was to use fuzzy logic as an auxiliary tool in the assessment of adaptability and stability, using grain‐yield data from flood‐irrigated rice, evaluated in different agricultural years. Eighteen rice genotypes belonging to flood‐irrigated rice breeding programme were evaluated over four agricultural years, 2012/2013 to 2015/2016, totalling 12 environments (3 sites × 4 years). The methodologies of Eberhart and Russell (1966), Lin and Binns (1988) modified by Carneiro (1998) and Centroid's were used. Fuzzy logic was applied to the results of these methodologies as a tool for interpretation and decision‐making regarding the recommendation of genotypes. Performances of the different flood‐irrigated rice genotypes were influenced by environmental conditions, thereby justifying the use of multiple adaptability and stability methodologies. The use of fuzzy logic in the selection of flood‐irrigated rice genotypes is a useful and promising tool in breeding programmes, allowing information from different parameters to be used to understand the influence of environmental variations on the performance of crop genotypes. [ABSTRACT FROM AUTHOR]

Responsible for approximately 70% of the world's coffee exports, Brazil is increasingly concerned about the quality of the coffees produced, given the growing demand for so-called specialty coffees. With this, the breeders need, besides the agronomic characteristics, to consider the physical and sensorial quality of the beans in the breeding programs. However, the greater the number of characteristics to be considered in the selection process, the higher the difficulty in selecting superior genotypes. In this context, multivariate analyzes can help to overcome this problem. In the light of the facts, the objective was to select Coffea arabica genotypes with a high simultaneous potential of variables of commercial interest, in three municipalities belonging to the Matas de Minas region—MG, Brazil, through factor analysis, using their scores as criteria or indices of selection for genotype identification. Multivariate analyzes were performed for each environment individually and, by commonality, three factors were established for each environment. The factors were interpreted as sensorial quality, sieve and vigor, in a similar way in the three environments. The interaction genotype by environment was maintained even after the summary of the variables in factorial complexes. The genotypes Catucaí Amarelo 24/137 and H419-3-3-7-16-4-1 excelled in relation to the factorial complexes, besides showing good adaptability and stability, consequently, they present great potential to improve the coffee production performance in the region of Matas de Minas. [ABSTRACT FROM AUTHOR]