Water stress effects on common bean genotypes with four growth habits

This study evaluated 22 common bean (Phaseolus vulgaris L.) genotypes for yield and yield components performance under drought stress conditions. The genotypes were grouped into four growth habits IIIa, IIIb, IVa and IVb, according to International Center for Tropical Agriculture (CIAT) classification. A split-plot design, laid out in a randomized complete block design (RCBD) with three replications was used in the study. Drought was imposed at flowering stage (terminal drought). Data were recorded on number of pods/plant, pod length, seed size and grain yield. Results showed higher significant differences (P<.001) between stressed and non-stressed genotypes in number of pods/plant (NPP), number of seeds/pod (NSP) and seed size (hundred seed weight). Similarly growth habits differed significantly amongst the genotypes in their response to water conditions. A comparison between all four growth habits showed that Genotypes VTTT 923/10/3, BCB2 and Sugar 131 (growth habit IIIa); A286 (growth habit IIIb); 12D/2, Kanzama (growth habit IVa) and MBC 33, Cim-climb 01-03-40 (growth habit IVb) were drought tolerant. Therefore, inclusion of these genotypes in the drought tolerance breeding programme is recommended.