The invention relates to a red leaf marking restoring line and a three-line
crossbreed selection and breeding method of the red leaf marking restoring line. Silver cotton II serves as a female parent, a red leaf marking parent 96-67 serves as a male parent, an F1 generation and an F2 generation are planted, red-leaf
fertility plants are selected from the F2 generation and are harvested, an F3 generation is planted, red-leaf
fertility plants are selected from the F3 generation, four-generation
selfing is continuously carried out,
plant lines with separated sterile lines are eliminated, and five single plants finally selected from a red-leaf
plant line serve as male parents; fertilization is conducted on a cytoplasmic sterile line 4PB404A to acquire a
crossbreed cotton, after the cross
breed cotton blooms,
pollen scattering conditions of the plants are detected, restoration ratio is calculated, a red leaf marking restoring line 11HF106R with the restoration ratio reaching 100% is selected and bred,
test cross is conducted on the red leaf marking restoring line 11HF106R and twenty-six cytoplasmic sterile lines, cotton Lumianyan 28 serves as comparison, a marking three-line combination 25MA*11HF106R which is good in production increasing effect is selected and bred. The method resists the risks of sterile plants caused by natural
outcrossing, improves variety purity, completely utilizes
crossbreed advantages, increases seed producing yield, reduces seed producing cost and improves production efficiency.