抄録
1. In the present research, the germination of F2 seed, and the external characteristics, fertility and the number of somatic chromosomes of trigeneric triple F2 hybrids (TperHRF2) raised from (Triticum persicum×Haynaldia villosa F1)×Secale cereale were studied.
2. 113 grains of F2 seed were obtained from 18 F1 individuals which were shown partially fertile, and all of the seed were sown in separate pots in October 1958 and 97 grains germinated and 87 of them matured (Table 1). The germination of F2 seed varies with the each parent, and the percentage of germination has been shown to vary from 50 to 100 for the seedlings, or from 0 to 100 for the matured F2 plants (Table 1).
3. As seen in Table 2, the number of somatic chromosomes of the 89 individuals of TperHRF2 hybrids was found to vary from 38 to 58.
4. Some individual differences were observed in the external characteristics of the F2 plants, even among the plants having the same number of chromosomes (Tables 3 and 4). The culm length of almost all of the F2 tended to be inferior to that of the parental plant (F1). And there seems to be no correlation between culm length and the number of chromosomes. The length of spikes and the number of spikelets per spike, in general, were superior to those of the parent (F1), excepting some individuals which were somewhat inferior to those of the parent. The length of awns, the most of the F2 which were raised from F1 having 2n=26 chromosomes were superior to those of the parental plant (F2), but in the other ones it was in general that they tended to be inferior to that of the parental plant (F1). The spikelet density of the most of F2 which were raised from the F1 having 2n=28 chromosomes were superior to those of the parents (F1), while in the remaining all the others were the same value or inferior to that of the parents. Generally speaking, the external characteristics of F2 plants were somewhat inferior to that of the parental plants (F1).
5. The external appearance of spikes of F2 plants having 2n=38-46 chromosomes violently revealed rye characteristics more than that of Haynaldia and wheat, ond those other ones having 2n=47-56 chromosomes resembled more closely Haynaldia or wheat, because there are the differences of consisting of chromosomes between the former group and the latter.
6. As can be seen in Table 5, 21 in 69 F2 plants show fertility though under natural selfing conditions it is not such a high percentage. And those values are progressively exceeding those of parental plants (F1)
