落花生種子休眠性之研究 III．種子休眠性之遺傳

Abstract

This report is the results of a study of the mode of inheritance of seed dormancy in peanuts. A Spanish type variety, Java 2, which is non-dormancy was crossed with Virginia Bunch 67 (Virginia type, long dormancy), Chiba Bunch (Virginia type, moderate seed dormancy), and NC-1 (Virginia, short seed dormancy) respectively. The reciprocal crosses were also made at the same time. The F2 populations, F3 families of all three crosses, and their reciprocals were analyzed. The F2 materials and their parents were planted in spring 19 at Taiwan Agricultural Research Institute in Taipei, and the F3 families were planted in autumn the same year (in Pingtung). The seed germination test for F2 plants and F3 families were conducted by using the seeds 14 days after harvest. The percentage of dormancy of any plant higher than 20% was considered as a dormant plant. The results indicated that the cross combinations, Java 2 × Virginia Bunch 67 and Java 2 × Chiba Bunch and, their reciprocals showed 3 dormant: 1 non-dormant segregating ratio. (Table 1). The F3 families showed that one-third of the families derived from dormant F2 plants are homozygote for seed dormancy while the other two-thirds are segregating. The non-dormant F3 plants resulted in all non-dormant F3 families (Table 2). However, in the cross-combination of Java 2 × NC-I and its reciprocal, the F2 segregating ratio did not agree with a 3:1 ratio, but the F3 families did agree with a 1:2:1 ratio. So it is concluded that the seed dormancy may be controlled by a single dominant gene. designated as D. The F2 population of Java × NC-I deviated from 3:1 ratio might be explained as that the dormancy period of Java 2 and NC.I was quite close which makes the classification more difficult.