Effect of mulch and irrigation on leaf water relation and pod yield of common bean in dry period of Bangladesh

Abstract

Field study was carried out to understand the effects of three mulches (Senna siamea leaf, straw and water hyacinth) and five irrigation regimes {IW (irrigation water)/CPE (cumulative pan evaporation) 1.0, IW/CPE 0.75, IW/CPE 0.50, IW/CPE 0.25 and no irrigation} on leaf water status and pod yield of common bean during the dry season of Bangladesh. IW/CPE 1.0, 0.75, 0.50 received 40 mm irrigation when CPE reached 40, 53 and 80 mm. IW/CPE 0.25 did not receive any inigation due to lower CPE than 160 mm during the study. Relative water content (RWC), water potential (Ψl) and stomatal conductance (gs) did not vary significantly among the mulches. These parameters, however, varied with the change of irrigation regimes but the variations were not significant up to IW/CPE 0.50 with all mulches. Green pod size and yield did not change remarkably among the mulches. Irrigation played significant role in pod size and yield. Significantly higher yield was recorded in IW/CPE 1.0 with straw and water hyacinth mulches, while under Senna leaf mulch pod yield did not vary much up to IW/CPE 0.75. The better performance of Senna leaf might be due to favorable soil environment. Therefore, common bean for green pod can be grown successfully at IW/CPE 0.75 with Senna leaf mulch during the dry season in central Bangladesh. © 2007 Academic Journals Inc.