1. In the present reports, the external characteristics, fertility and the number of somatic chromosomes of trigeneric triple F
1 hybrids raised from
Triticum persicum×Haynaldia villosa F
1×
Secale cereale (Tper HRF
1) and
T. durum×H. villosa F
1×
S. cereale (Tdur HRF
1) are treated respectively.
2. The percentage of the triple F
1 plants againts the number for the pollinated florets in the hybrid Tper HRF
1 was higher than that of the hybrid TdurHRF
1 (Table 1).
3. The number of somatic chromosomes of
Triticum-Haynaldia-Secale trigeneric triple F
1 hybrids was found to vary from 25 to 32 in TperHRF
1 and from 24 to 32 in Tdur HRF
1 (Table 2 and 3). And the somatic number of chromosomes of eu-trigeneric triple F
1 hybrids in these two combinations is 28. This number corresponds exactly to the sum of the gametic numbers of the three parental plants (
Triticum persicum or
durum 28+
Haynaldia villosa 7+
Secale cereale 7=28). 7 chromosomes out of the 25-32 or 24-32 chromosomes as the somatic number of these two trigeneric triple F
1 hybrids are from
S. cereale as the pollen plant, and the remaining 18-25 or 17-25 chromosomes must have been from TperHF
1 or TdurHF
1 as the mother plants. The number of somatic chromosomes of TperHF
1 and TdurHF
1 in these two combinations was found to be 21 respectively, therefore, up to 21 of the 17-25 chromosomes derived from mother plants are due to the irregular distribution of the chromosomes or to the formation of the equatorial plate, but the 1-4, which is in excess of 21, may be due to the non-disjunction of the chromosomes in the meiosis of the mother plants. And it is difficult to as-certain whether those surplus chromosomes came from the
Triticum or the
Haynaldia.
4. The variation was observed among these groups and among the individuals of each group, in the external characteristics of these two trigeneric triple F
1 plants. The remarkable differences were observed among the individuals in each group, due perhaps to the different constitution of chromosomes in the individuals of each group, though they have the same number of chromosomes. The external characteristics of these F
1 plants and their parental plants are shown in Table 4 and Photo. 1. Generally speaking, although these F
1 plants possess the external characteristics of the three parents, they resemble somewhat more closely to the original mother plant
Triticum (Photo. 1).
5. Most of the individuals of TperHRF
1 and TdurHRF
1 were almost sterile, but in extremely rare cases, some anthers opened and some grains were obtained in natural selfing (Table 5) and by sowing them in October 1958, many F
2 plants were raised.
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