The invention discloses a breeding method of an early maturing cowpea variety. The method includes the steps of: (1) screening early maturing, low temperature resistant and high-yielding cowpea
germplasm resources and materials from cowpea local varieties and
germplasm resources, performing
selfing purification according to a breeding goal, then preparing
hybrid combination for conventional breeding, and carrying out
selfing separation and purification; (2) conducting
sowing and
seedling raising on a self-bred 6th generation variety or strain, and performing
seedling stage low temperature and weak light tolerance identification; (3) investigating the
germination potential on the 6th day of
seedling raising, investigating the seedling emergence, seedling height, stem
diameter,
cotyledon length*width on the twelfth day of seedling raising, and calculating a low temperature and weak light tolerance index according to the investigation result; and (4) performing
statistical analysis on the identification result, screening out the low temperature and weak light tolerance variety or strain with a
high index and sending the variety or strain to a variety comparison test, thus obtaining the low temperature and weak light tolerance early maturing cowpea variety. Seedlings and adult plants have high
positive correlation with environmental condition response, by means of early stage seedling screening, the low temperature and weak light tolerance of the variety or strain can be identified at the seedling stage, and the variety or strain with poor low temperature and weak light tolerance can be eliminated, thus effectively reducing the number of screened varieties or lines, greatly alleviating the
workload of field test, and accelerating the breeding process.