Levels of Resistance to the Whitebacked Planthopper, Sogatella fardfera (Homoptera: Delphacidae) in Rice Varieties with the Same Major Resistance Genes

Abstract

Rice varieties were evaluated to determine the levels of resistance to Sogatella furcifera among those having the same major resistance genes Wbph 1 and Wbph 2. Tests conducted were the seedbox screening of the varieties for plant damage, and S. furcifera survival and population growth on the test varieties. Degree of variation in levels of resistance among varieties with the same gene was very high, especially in the seedbox screening and population growth test. IR2035-117-3, the resistant check with both genes, Wbph 1 + Wbph 2 and two Wbph 2 gene varieties, ‘Chempan’ and ‘Cheriya Chittari’, had the highest levels of resistance as based on the survival and population growth tests. The difference in levels of resistance among varieties having the same major gene indicates that minor genes play a significant role in the expression of S. furcifera resistance in rice.