Management of Oil Palm Bunch Failure in High Sex Ratio Palms

Abstract

Bunch failure due to insufficient pollen is a serious problem in all the oil palm growing countries. It is observed that the main problem is due to lack of pollinating weevils as a result of inadequate male flowers in the plantations. The establishment of pollinating weevils in high sex ratio palms is a critical requirement for oil palm productivity. Bunch failure due to lack of pollination in high sex ratio palms was found to cause more than 90 per cent yield loss. The problem was severe, particularly, in isolated young oil palm plantations. Presence of limited number of male flowers led to fewer pollinating weevils even after inundating releases leading to poor yield. Intercropping with crops like banana and sugarcane which require great amount of water encouraged the emergence of more female than male flowers. Assisted pollination by sprinkling pollen grains on female inflorescences proved effective to a certain extent. Various treatments like severe pruning of fronds and application of gibberellic acid in high doses proved effective in mitigating the problem. These allowed natural pollination with the emergence of more male flowers and establishment of pollinating weevils. Keywords: Bunch failure, thrips, pollinating weevils, inundating releases, gibberellic acid.