They may provide entry points for lethal secondary attacks by the palm weevil Rhyncophorus or by other pathogens, in some countries (Bedford, 1980). Attack by adults may reduce yield and kill seedlings. In younger palms the effect of damage can be much more severe (Wood, 1968 1976). rhinoceros bores into the base of cluster of spears, causing wedge shaped cuts in the unfolded fronds. From artificially pruned leaf damage stimulation studies it was observed that damage to 50% fronds corresponds to leaf area reduction of 13% and decrease in nut yield by 23% (Young, 1974). (1963) has reported a loss in yield of 5.5 to 9.1% due to beetle attack. In India damage of inflorescence is also reported in severely infested areas which cause reduction in yield up to 10% (Nair, 1986). Some of the crushed fibre is pushed outside the entrance hole, where it indicates the insect’s presence. The imagos are the destructive stage, they bore into the crown of the palm resulting in wedge shaped or \"V\" cuts in the fronds that unfurl. The coconut rhinoceros beetle is one of the most damaging insects to coconut palms and African oil palm in southern and south- east Asia and the Western Pacific islands. The most common pesticide is cypermethrin, which has been used to manage the rhinoceros beetle in both nurseries and plantations.There are natural factors that keep the beetle under control in its native range, its introduction into insular habitats without these natural control factors allows it to reproduce quickly and spread to become a serious pest (Nishida
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