Growth and yield of Jatropha curcas l. as influenced by different regimes of apical bud removal

Abstract

An experiment was conducted on the influence of time of apical bud removal on the growth and yield of Jatropha curcas which has low performance due to poor production practices. Removal of apical dominance by decapitation has potential to improve yield of plants. However, the capacity at which decapitation can improve growth and yield of Jatropha curcashas not been adequately explored. The effects of decapitation was assessed on growth in pots in a research garden, University of Ibadan and growth and seed yield were examined on the field, at 6, 10, 14 and 18 weeks after sowing in the Institute of Agricultural Research and training, Ibadan. A control (without decapitation) was used as check. The experiments were arranged in pot and field studies using CRD and RCBD, respectively replicated four times. Number of leaves, number of branches, leaf area(cm²), dry weigh(g), days to flowering, days to fruiting, and days to fruit maturity and seed yield (g) were determined. Data were analysed using descriptive statistics and ANOVA at α_0.05. The results from the pot experiment showed that plants decapitated at 6weeks had significantly (p>0.05) higher number of branches (6.3), Leaf area (1647.6cm2) and Dry weight (245.0g) than control (1.8; 898.7cm2 and 188.5g, respectively) and other treatments. On the field, days to flowering and days to fruit maturity showed that  control plants (220.5 and 310.3)flowed and produced matured fruits earlier thanplants decapitated at 6weeks (223.8; 314.3).This was followed by decapitation at10 weeks(230.0; 321.0) and decapitation at 14weeks (238.0; 321.0).Plants decapitated at18weeks were the last to fruits and matured  (240.8; 323.5). Highest Seed yield was at D6 (75.8) and least in control (29.0). The results showed that decapitation at six weeks after sowing increased growth and seed yield of Jatropha curcas.