Damages of Brown Planthopper, Nilaparvata lugen (StɿI) on Non Photosensitive Certified Rice varieties in the Eastern Region

Abstract

Hawm Klawng Luang 1, Khao’ Jao Hawm Suphanburi and Pathumthani 1 were studied. Suphanburi 90 and RD7 were resistant and susceptible check respectively. When BPH were having a feeding choice, BPH on rice plants of RD 7, Khao’ Jao Hawm Klawng Luang 1 and Khao; Jao Hawm Suphanburi and all rice plants died within 30 days. BPH on Pathumthani 1 and Suphanburi 90 reproduced 2 generation of the nymphs within 98 days. However, all rice plants of Pathumthani 1 died within 100 days. When the damages of BPH was occurred at level of economic threshold, numbers of BPH on RD 7 was the highest. Numbers of BPH on Khao’ Jao Hawm Klawng Luang 1 was the lowest due to higher number of dead plants. All plants of Khao’ Jao Hawm Klawng Lunag 1, Khao’ Jao Hawm Suphanburi, RD 7 and Pathumthani 1 died within 30, 35 and 40 and 45 days respectively. When the damages of BPH was occurred at level of higher than economic threshold, BPH on rice plants of RD 7, Khao’ Jao Hawm Klawng Luang 1 and Khao’ Jao Hawm Suphanburi and all plants died within 20 days prior to reproduce the nymph. BPH on Pathumthani 1 and Suphanburi 90 reproduced the nymphs. All plants of Pathumthani 1 died within in 35 days. Comparision between the damages of
BPH at higher and at level of economic threshold, plants of Khao’ Jao Hawm Klawng Luang 1 and Pathumthani 1 died earier in 10 days when damages of BPH at higher level of economic threshold Similarly, RD 7 and Khao’ Jao Hawm Suphanburi died earier in 15 days.