Abstract:

In order to increase the per unit area yield of common buckwheat (F. esculentum), according to the technical way of corn heterosis utilization, we have cultivated 3 parent lines: common buckwheat ‘dwarf B inbred line’, ‘wild relative self-bred line I’ and ‘wild relative self-bred line II’, and made two combinations for hybrid seed production and utilization. Through observing and counting the pistil pollen loads and the rate of positive hybridization and negative hybridization in field, it was found that: taking a sample at 2:00pm at full-bloom stage and observing with a microscope, pollen grains of 3 columns of stigma in each flower varied from 15 to 55 with the average of 23. The rate of the positive hybridization (dwarf B line × wild relative line) was 60%-65%; the rate of the negative hybridization (wild relative line × dwarf B line) was 30%. In production, the difference was significant between the F₁ plant and the parent plant in the same hole in bunch planting field. The F₁ plant was strong and lush, and its yield was more than 3 times that of the parent plant, indicating that the F₁ generation had strong heterosis. Its yield increase in the regional test was 11.7% compared with the parent plant and 29% compared with other varieties. The study proposed that wild relatives are a kind of precious germplasm resource, and the strong heterosis in common buckwheat and wild relatives could be used to improve the per unit area yield of common buckwheat. The study also found that the hybridization rate could not achieve 2/3 of the theoretical value because of the poor flower synchronization.

Key words: common buckwheat, wild relatives, hybrid, heterosis, yield