Breeding method of japonica rice sterile line during early blossoming

Abstract

The invention discloses a breeding method of a japonica rice sterile line during early blossoming, and belongs to the field of rice heterosis utilization. The breeding method comprises the following steps that indica rice or wild rice resources which bloom before 9 o'clock in the morning, have good heterozygosity and good outcrossing habit are selected, and a japonica rice maintainer line serversas female parent with the indica rice or wild rice resources for hybridization; single plants which bloom at about 10 o'clock in the morning and have good heterozygosity are selected as segregation generations, and pedigree selection is carried out until stable; existing markers are utilized, and new molecular markers are mined to assist in selection; the maintainer line and the sterile line are hybridized and backcrossed, and the breeding process is accelerated through high-density direct seeding; and south-north shuttling breeding is carried out to breed a new japonica rice sterile line during early blossoming. The japonica rice sterile line bred by the method is early in flowering time, high in stigma exposure rate and high in outcrossing setting rate.

Description

technical field [0001] The invention belongs to the field of utilization of plant heterosis, and in particular relates to a method for selecting a male sterile line of early flowering japonica rice. Background technique [0002] Rice is one of the most important food crops in the world. More than half of the world's population depends on rice as a staple food. The output of rice is related to the food security of the world. Utilization of heterosis is an effective way to increase rice yield. Great achievements have been made in the development of hybrid indica rice in China, but the development of hybrid japonica rice is still relatively slow. [0003] Low seed yield is an important bottleneck factor restricting the development of hybrid japonica rice. Among them, the flowering timing of the parents is the key factor leading to the low yield of hybrid seeds. Generally, indica rice blooms early and japonica rice blooms late. The japonica rice CMS line is directly bred from...

AI Technical Summary

Problems solved by technology

After the restorer line blooms and looses pollen, the CMS line blooms belatedly, resulting in a low pollination and seed setting rate on the day of flowering of the CMS line

In addition, the stigma exposure rate of the japonica CMS line is poor, and the rate of pollination and seed setting on the day of non-flowering is also quite low, resulting in low seed production yield