Water stress effect on agro-morphological and physiological parameters of three local cultivars of maize (Zea mays L.) of South Benin
Water deficit in tropical countries is the main factor limiting agricultural production. This study aimed at evaluating the level of resistance to water deficiency of three local maize cultivars in Benin. The effects of water stress induced supply of 100 (control), 50 and 25 % of the Readily Usable Reserve (RUR) from the 40th day after sowing to the end of the production cycle were studied. The experimental design used was a split plot with 4 replicates. Phenological, agro-morphological and agro-physiological parameters of plants were evaluated. Water deficit reduced plants height, root volume, root dry matter and total leaf area during the flowering stage. The date of female inflorescence setting was extended by water deficiency. Water deficiency also reduced the mean number of cobs per plant from 0.855 ± 0.38 (100% RUR) to 0.64 ± 0.019 (50% RUR) and 0.58 ± 0.17 (25% RUR). Furthermore, 1000 grains weight dropped from 264.63 ± 53.58 g (100 % RUR) to 223.88 ± 37.9 g (50 % RUR) and 217.63 ± 42.66 g (25% RUR). The cultivar Bafogbali was the most resistant to water stress. The variety EV DT 97 and the cultivar Souantokoui were the most affected by the water deficiency.
Keywords: Water pattern, drought, easily usable reserves, Zea mays, Benin.