Pruning Techniques for Jatropha curcas L. to Increase Seed Yield Production

In this study, the effects of different pruning heights and number of branches left were evaluated to determine the most effective pruning height and optimum number of branches to be left after branch thinning to increase seed yield production of Jatropha curcas. The experiment, which was conducted at the MMSU Experimental Station from 2009-2011, was laid-out in Split plot design and was replicated three times. The treatments were as follows: Factor A – (Pruning height) A1 – No pruning; A2 – 50 cm; A3 – 60 cm; and A4 – 70 cm and Factor B (number of branches left) B1 – 8 branches; B2 – 10 branches; and B3 – 12 branches. The main effects of pruning height were significant in all the parameters tested. J. curcas with 0.70cm pruning height consistently produced the most number of branchlets (42.44), inflorescence plant -1 (78.33), fruit cluster -1 (7.11), as well as total fruits plant -1 (533.44), seed yield plant -1 (0.86kg), and seed yield ha -1 2161.47kg). This was comparable in plants with 0.60cm pruning height on the number of branchlets, number of inflorescence plant -1 , total number of fruits plant -1 , seed yield plant -1 , and seed yield ha -1 . The shortest period (8 days) to initiate flower buds was observed from the unpruned plants, however, they had the least results in all the other parameters. Likewise, significant main effect of the number of branches left after branch thinning was noted in all the parameters except on the number of days prior to flower bud initiation. J. curcas with 12 branches consistently exhibited the most number of branchlets (42.33), number of inflorescence plant -1 (74.92), fruit cluster -1 (6.01), total fruits plant -1 (467.92), seed yield plant -1 (0.71kg), and seed yield ha -1 (1782kg). Similar trends, however, were noted in plants with 10 branches in terms of the number of branchlets, number of inflorescence, and seed yield ha -1 . No interaction effect of pruning height and number of branches left was observed in all the other parameters tested.