Effects of Salicylic Acid on Probing and Oviposition of the Rice Plant- and Leafhoppers (Homoptera : Delphacidae and Deltocephalidae)

Although the rice plant- and leafhoppers attempted only a superficial probing to distilled water, they probed deeply and repeatedly into the rice plant sap, consequently a number of elongated and branched stylet sheaths were produced. Salicylic acid provoked a significantly stimulated probing of N. lugens, but did not elicite remarkable probing responses of the other species. N. lugens oviposited preferably in the salicylic acid media, while only a few eggs were laid in the salicylic acid-free control medium. On the contrary, the salicylic acid media were not preferred for oviposition of L. striatellus to the control medium which a considerable number of eggs were deposited in. The other species laid few or no eggs in neither salicylic acid media nor the control medium.