Transposon Polymorphism and Its Potential Impacts on Brown Planthopper (Nilaparvata lugens Stal) Resistance in Rice (Oryza sativa L.)

The brown planthopper (BPH) is a major pest in rice cultivation, significantly affecting both yield and quality; accordingly, exploring and utilizing anti-herbivory genes to enhance rice's inherent resistance to BPH can be an effective strategy for mitigating infestation. The effects of transposon insertion polymorphisms (TIPs) on rice's resistance to insect pests have not been reported. In this study, through the identification of transposon insertion sites in susceptible and resistant rice varieties, a total of six possible candidate insect resistance genes were potentially located. Among them, a segment of the LTR/Copia transposon insertion was verified in the promoter of LOC_Os04g02720, which carries a cis-acting element binding site in rice involved in the abscisic acid reaction. Quantitative analysis showed a significant difference of the gene expression between insect-resistant and insect-susceptible varieties (p < 0.05). This study provides insights into the functional analysis of transposons and population transposon polymorphisms, whereas the identification of candidate insect resistance genes offers a theoretical foundation for the development of insect-resistant rice varieties.