PRODUCTION OF ONE GENERATION HYBRID SEED, AND PRODUCTION, MAINTENANCE AND PROLIFERATION OF THE PARENT SEED LINES

摘要

PROBLEM TO BE SOLVED: To develop a variety of uniform growth and quality capable of efficiently producing an F1 hybrid seed and manifesting high productivity by treating a plant manifesting heteromorphous flower self-incompatibility under specific conditions. SOLUTION: Only a long-styled flower individual is selected from a plant under isolated conditions and mutually crossed by artificial pollination or natural crossing to thereby grow a line composed of only the long-styled flower individual when producing an F1 hybrid seed in a plant manifesting heteromorphous flower self-incompatibility including plural varieties of Fagopyrum esculentum Moench such as a variety of Kitawase-Soba, Kitayuki, Botan-Soba or Shinano-Natsu-Soba(varieties of buckwheat). The resultant line is then crossed in a state isolated from other lines under artificial or natural conditions to proliferate the seed and produce a long-styled flower individual line. A line B containing only a short-styled flower individual or both of the short- styled flower individual and the long-styled flower individual is cultivated near the line A composed of only the long-styled flower individual and a seed riped in the line A is collected to produce the seed of the line A fertilized with the pollens of the line B (F1 hybrid seed of the lines A with B).