Probing Behavior of Three Biotypes of Nilaparvata lugens (Homoptera: Delphacidae) on Different Resistant and Susceptible Rice Varieties

Abstract

The feeding activity of biotype 1, biotype 2, and biotype 3 of Nilaparvata lugens (Stal) on differentially resistant rice varieties ‘Taichung Native l’ (‘TNI’) (no resistance gene), ‘Mudgo’ (Bph 1 gene) and ‘ASD7’ (Bph 2 gene), was monitored with a direct current variant of an electronic recording device, ‘TN1’ is susceptible to all three biotypes. ‘Mudgo’ is susceptible to biotype 2 but resistant to biotypes 1 and 3. ‘ASD7’ is susceptible to biotype 3 but resistant to biotypes 1 and 2. Electronically recorded waveforms corresponding to planthopper probing, salivation, and ingestion differed significantly on the leaf sheaths of susceptible and resistant rice plants. All three biotypes probed more readily and ingested longer on their respective susceptible varieties than on resistant varieties. The quantity of food ingested and assimilated also was significantly higher on susceptible than on resistant plants. Microsections of leaf sheath tissue were made to correlate stylet position and probing activities of the planthopper on susceptible and resistant rice varieties.