Population structure of brown planthopper (Nilaparvata lugens, Hemiptera: Delphacidae) and attack level in endemic area of Padang city, Indonesia

Endemic areas of brown planthopper or BPH (Nilaparvata lugens Stal 1854, Hemiptera: Delphacidae) is an area that always provides BPH in each planting season. Kuranji and Nanggalo Sub-districts are two endemic areas in Padang City. The study aimed to determine the population structure of BPH on IR 42 variety in endemic area of Padang City. The study used a survey method by collecting BPH using a modified hand vacuum, collected from 20 samples of IR 42 variety randomly on two fields in each sub-district. The collections were carried out 3 times at 2-week intervals. The research in vegetative phase was began when rice plant was 3 weeks old after planting, while the research in generative phase was began when the rice plant released the first panicle. The results showed that overlapping generations occurred between nymph and adult (brachypteran & macropteran, male and female). The dominance as a whole was nymph (70.7%). Macropteran population was higher than brachypteran. Based on the phase of rice, BPH in generative phase was higher than vegetative meanwhile based on district, BPH in Kuranji was higher than Nanggalo. Attack percentage ranged from 51.6 – 94.1% and attack intensity ranged from 6.01-10.55%.