Phytotoxic Effects of Gliricidia sepium Prunings on Maize Germination and Growth

Gliricidia sepium prunings are known to have both positive and negative effects on agrocrops. In this study, it's phytotoxic effects on maize seedlings were evaluated under both laboratory and field conditions. In the laboratory, a leachate of dry Gliricidia prunings (leaves) was prepared and used to irrigate maize seeds during germination and early growth. Three levels of leachate concentrations (25%, 50% and 100%) and control (distilled water) were used. Germination percentage and fresh weights of radicles and shoots were taken 10 Days After Planting (10 DAP). In the field, dry Gliricidia prunings were applied on experimental plots (0.5mx0.5m) as mulch at the rate of 10 tons ha-1 at 0, 1, 2 and 3 weeks before planting the maize seeds and a control where no mulch was added. Each plot was planted with 60 maize seeds and artificially irrigated. Germination percentage, leaf chlorosis and seedling biomass at 10 and 20 DAP were measure for each treatment. In the laboratory, Gliricidia leachate slightly reduced germination and depressed radicle and shoot growths of maize seedlings significantly (ANOVA: P,0.05). In the field there was no significant reduction in maize seed germination and growth due to addition of mulch. However, the lowest germination and biomass and the highest leaf chlorosis were recorded in the plots where mulch was added 10 weeks before planting the maize seeds