II. 9 Progeny of Barley-Wheat intercrosses.
George Fedak. Ottawa Research Station. Central Experiment Farm. Ottawa, Ontario. K1A OC6 Canada. "R"
Our efforts at intercrossing wheat and barley have resulted thus far in the production of the reciprocal hybrids, an alloplasmic wheat haploid and backcross progeny as shown in Figure 1. Boch hybrids were obtained at low frequency since their synthesis was quite difficult to achieve. Expressed as seedlings obtained from florets pollinated the barley and wheat hybrid was obtained at a frequency of .77% (Table 1) while the reciprocal hybrid, the wheat x barley combination was obtained at a frequency of .22%. The latter hybrid was even more difficult to obtain than the data indicate. The data represent the first successful attempt but several unsuccessful attempts preceded this one.
One haploid has been obtained from the barley-wheat intercrosses thus far. This was an alloplasmic wheat haploid i.e. with 21 wheat chromosomes in a barley cytoplasm obtained from the barley x wheat combination. It was apparent that the barley cytoplasm had little or no effect on the morphology or meiotic behaviour of the alloplasmic haploid as it was a typical wheat haploid in both morphology and meiotic behaviour.
The reciprocal barley-wheat hybrids had the expected somatic chromosome number of 28 and both were typically wheat-like in spike morphology except for slightly awnletted lemmas which were apparently inherited from Betzes barley. Electrophoetic examination of leaf tissue esterases of both hybrids revealed the presence of both parental banding combinations indicating that the barley genome was also expressed at this level of resolution. Meiotic chromosome behaviour was similar in both hybrids. Hyperploid metaphase I cells i.e. meiocytes with more than 28 chromosomes were detected in both hybrids though at different frequencies. This abnormality was attributed to abnormalities at anaphase of premeiotic mitosis. Thus far, chromosomes doubling attempts using colchicine have failed so the material is being vegetatively propagated. Despite the failure of chromosome doubling both hybrids showed the ability to form 28 chromosome egg cells since 40 chromosome progeny were obtained from both hybrids following pollination with Chinese Spring. The backcrossing is continuing in an effort to establish additional lines of Betzes in Chinese Spring.
