title: Allozyme variation among biotypes of the brown planthopper Nilaparvata lugens in the Philippines.
abstract: Allozyme variation was studied in three Nilaparvata lugens biotypes infesting specific rice varieties and a biotype infesting a weed grass, Leersia hexandra. Of the 20 enzymes in N. lugens for which activity was noted, 9 were polymorphic. Eleven enzyme loci were monomorphic for the same allele in all biotype populations; the rest were polymorphic for two or more alleles. The mean number of alleles per polymorphic locus was 2.3, while the mean number of alleles per locus was 1.5; heterozygosity ranged from 0.02 to 0.06 (biotype 1 greater than biotype 3 greater than Leersia-infesting biotype greater than biotype 2). Allelic frequency differences were observed in five loci among the four biotypes. However, the coefficient of genetic identity (I) of 0.99+ showed that the four biotype populations were genetically close relatives or merely populations of N. lugens undergoing genetic differentiation.
authors.affiliation: Division of Entomology, International Rice Research Institute, Manila, Philippines.
authors.forename: R C
authors.initials: RC
authors.lastname: Saxena
authors.forename: C G
authors.initials: CG
authors.lastname: Demayo
authors.forename: A A
authors.initials: AA
authors.lastname: Barrion
mesh_terms: D000483:Alleles; D000818:Animals; D004798:Enzymes / Q000235:genetics*; D005787:Gene Frequency; D014644:Genetic Variation; D006579:Heterozygote; D007313:Insecta / Q000145:classification / Q000235:genetics*; D012275:Oryza / Q000469:parasitology*; D010679:Philippines; D010940:Plant Proteins / Q000235:genetics*; D011110:Polymorphism, Genetic
chemical_list: D004798:Enzymes; D010940:Plant Proteins