Effects of Nitrogen, Phosphorous and Potassium on Host-Choice Behavior of Brown Planthopper, Nilaparvata lugens (Stål) on Rice Cultivar
文摘
The brown planthopper (BPH), Nilaparvata lugens (Stål) (Homoptera: Delphacidae) is a major pest of many rice growing countries worldwide. It has been observed that one rice field is severely infested by BPH while an adjacent field left untouched. We hypothesized that differences in nutrient content in rice plants may explain this behavior. BPH feeding and oviposition behavior was evaluated on rice plants that had been grown under a range of fertilizer treatments. Tissue samples from experimental rice plants were analyzed for percent N, P, K, Si, free sugars and soluble proteins which were regressed with BPH host choice parameters. A completely randomized design with four replications in a factorial scheme was used in experiments where levels of soil N, P and K were taken as factors. Nymph feeding preference did not differ significantly among different nutrient treated rice plants. Adult females preferred to feed and oviposit on rice plants fertilized with N but it showed negative preference with K supplementation, while P had no marked effect. The position of feeding and ovipositing shifted gradually from lower to upper of leaf sheath and then to leaf blade with decrease of N fertilization to the rice plant. Host choice of BPH for feeding and ovipositing were positively associated with plant tissue concentrations of N, total free sugars and soluble proteins, negatively with Si but not with P and K. Plant tissue biochemical those are associated with BPH host preference may regulate how fast and where they settle on a rice plant.
