Performance and adaptation of opaque black bean genotypes in environments with and without terminal drought

Abstract

The drought at the end of the reproductive stage (terminal), is one of the main environmental factors that limit the yield of beans in the sowings of residual moisture in Veracruz and Chiapas, Mexico. The objective of this research was to determine the yield and adaptation of 13 bean genotypes under conditions of residual moisture in localities with and without terminal water stress. The new Verdín variety, together with 10 advanced lines and the Negro Tacaná and Negro Jamapa varieties were evaluated in three environments of Veracruz and Chiapas in Autumn-Winter (A-W) of 2013 and spring-summer (S-S) of 2014. The experimental design was complete random blocks with three repetitions. During the crop cycle, rainfall was recorded and the dynamics of the usable humidity of the soil was determined. The response variables were: days at physiological maturity and grain yield. Combined analyzes of the six test environments were carried out and also an analysis to determine the stability of yield and adaptation of the genotypes. The dynamics of the usable humidity indicated that, in Medellin and Ocozocoautla, in A-W of 2013 and in Medellin and Cintalapa in S-S of 2014, conditions of terminal drought prevailed, while in Tlapacoyan, in both production cycles, the plants had no stress by humidity. Thus, the differences in moisture availability during the reproductive stage, through the test locations, affected the productive response and the duration of the crop cycle of the genotypes evaluated. Among the genotypes, the Verdín variety showed high yield with and without terminal drought with 1121.7 and 1568 kg ha-1, its yield was significantly (p> 0.01) higher than that of the commercial controls, Negro Tacaná and Negro Jamapa.