BIOCHEMICAL-GENETIC STUDIES ON WILD POPULATIONS OF 3 SPECIES OF GREENLEAFHOPPERS, NEPHOTETTIX, FROM PENINSULAR MALAYSIA

Nine populations of three species of Nephotettix (Insecta: Hemiptera) from Peninsular Malaysia were analysed for nine enzymes comprising 11 loci. Nei's (Genetics 89, 583, 1978) genetic distance, D, between N. v irescens and N. malayanus was 0.181, that between N. virescens and N. nigropictus was 0.283, and that between N. malayanus and N. nigropictu s was 0.203. The genetic distance between N. nigropictus from rice pla nt and from the weed-grass L. hexandra at Universiti Perztanian Malays ia was 0.004 and their genetic identity was 0.996, thus indicating tha t this insect species feeds on both host plants. The proportion of pol ymorphic loci and the observed heterozygosities were higher in N. nigr opictus, with a wider range of host plants, than in N. virescens and N . malayanus, restricted to rice and L. hexandra, respectively.