This invention provides a
molecular marker primer tightly linked to the major
brown planthopper resistance
gene Bph57 in rice, along with its marking method and application. This invention utilizes
genetic linkage analysis of individual F2 plants obtained from crossing the
insect-resistant rice variety “Daomushe Late Bengu” (C9) (♂) with 9311 (♀), combined with the
brown planthopper resistance levels of F3 families. This analysis identifies the major resistance
gene Bph57 carried by the
insect-resistant variety C9. The Bph57 region is narrowed down to an approximately 90kb fragment defined by flanking markers 2M26.442 and 2M26.536, and tightly linked to
molecular marker 2M26.762. The
molecular marker 2M26.762 of this invention effectively detects whether the
insect-resistant variety C9 and its derived varieties (lines) contain this major resistance
gene locus, significantly improving the selection efficiency for
brown planthopper resistance and obtaining brown
planthopper-resistant rice varieties (lines) containing Bph57.