title: The genetic basis of population fecundity prediction across multiple field populations of Nilaparvata lugens.
abstract: Identifying the molecular markers for complex quantitative traits in natural populations promises to provide novel insight into genetic mechanisms of adaptation and to aid in forecasting population dynamics. In this study, we investigated single nucleotide polymorphisms (SNPs) using candidate gene approach from high- and low-fecundity populations of the brown planthopper (BPH) Nilaparvata lugens Stål (Hemiptera: Delphacidae) divergently selected for fecundity. We also tested whether the population fecundity can be predicted by a few SNPs. Seven genes (ACE, fizzy, HMGCR, LpR, Sxl, Vg and VgR) were inspected for SNPs in N. lugens, which is a serious insect pest of rice. By direct sequencing of the complementary DNA and promoter sequences of these candidate genes, 1033 SNPs were discovered within high- and low-fecundity BPH populations. A panel of 121 candidate SNPs were selected and genotyped in 215 individuals from 2 laboratory populations (HFP and LFP) and 3 field populations (GZP, SGP and ZSP). Prior to association tests, population structure and linkage disequilibrium (LD) among the 3 field populations were analysed. The association results showed that 7 SNPs were significantly associated with population fecundity in BPH. These significant SNPs were used for constructing general liner models with stepwise regression. The best predictive model was composed of 2 SNPs (ACE-862 and VgR-816 ) with very good fitting degree. We found that 29% of the phenotypic variation in fecundity could be accounted for by only two markers. Using two laboratory populations and a complete independent field population, the predictive accuracy was 84.35-92.39%. The predictive model provides an efficient molecular method to predict BPH fecundity of field populations and provides novel insights for insect population management.
authors.affiliation: Key Laboratory of Biodiversity Dynamics and Conservation of Guangdong Higher Education Institutes, State Key Laboratory of Biocontrol, Sun Yat-sen University, Guangzhou, 510275, China.
authors.forename: Zhong Xiang
authors.initials: ZX
authors.lastname: Sun
authors.forename: Yi Fan
authors.initials: YF
authors.lastname: Zhai
authors.forename: Jian Qing
authors.initials: JQ
authors.lastname: Zhang
authors.forename: Kui
authors.initials: K
authors.lastname: Kang
authors.forename: Jing Heng
authors.initials: JH
authors.lastname: Cai
authors.forename: Yonggui
authors.initials: Y
authors.lastname: Fu
authors.forename: Jie Qi
authors.initials: JQ
authors.lastname: Qiu
authors.forename: Jia Wei
authors.initials: JW
authors.lastname: Shen
authors.forename: Wen Qing
authors.initials: WQ
authors.lastname: Zhang
mesh_terms: D000818:Animals; D002681:China; D005260:Female; D005298:Fertility / Q000235:genetics*; D005787:Gene Frequency; D017344:Genes, Insect; D005828:Genetics, Population; D006430:Hemiptera / Q000235:genetics* / Q000502:physiology; D015810:Linkage Disequilibrium; D008957:Models, Genetic; D008969:Molecular Sequence Data; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide
keywords: brown planthopper; fecundity; population structure; predictive model; single nucleotide polymorphism