Abstract
The chemical factor in rice plant attracting Nilaparvata lugens was extractable with ether and proved to be composed of multiple neutral compounds. The gas chromatogram of the active fraction indicated the presence of more than 27 compounds which were separated by chromatographic technique and identified as shown in Table 1. The planthoppers were well Ttracted to the mixture of these 27 compounds (14 esters, 7 carbonyl compounds, 5 alcohols, and 1 isocyanurate) and their activity was located in the carbonyl compounds plus isocyanurate, but the attractancy of these compounds was lower than that of the original active fraction. The gas chromatogram of the mixture was superimposable on that of the active fraction except for some minor differences as shown in Fig. 4, suggesting that minor components may play an important role for attractancy of rice plant against N. lugens.
