Abstract
For the purpose of studying the inheritance of the shooting time (the time at which the first panicle escapes from the leaf-sheath) in rice, the authors made in 1920 two crosses Homura No. 8×Sekitori No. 15 and Sekitori No. 15×Mubô-Aikoku No. 1. In each cross, an F1 plant was obtained in 1921. All the seeds raised from the F1 plants were sown in 1922, and two F2 families were produced. The numbers of F2 plants amount to 1, 061 in Homura No. 8×Sekitori No. 15, and 903 in Sekitori No. 15×Mubô-Aikoku No. 1. In 1923, 60 F3 families, in each cross, issued out of some selected F2 plants, each family containing about 120 plants. Every year a certain number of plants of these three parental strains were also grown for comparison. With every plant of the hybrid and parental strains, the number of days from sowing to shooting was observed, the total number of the plants thus inspected being 17, 851.
