| Hybrids between Aegilops triaristata (4x)
and Ae. comosa, Heldreichii and uniaristata
Takumi TSUCHIYA Beppu University, Beppu, Japan Though a great many hybrids have been reported in the genus Aegilops, no reports have appeared concerning the combination, Ae. triaristata (2n=28) and Ae. comosa (2n=14), which the author has successfully produced. One hybrid plant was raised from 7 seeds obtained from 10 florets of the cross, Ae. triaristata No. 3 x Ae. comosa No. 1. The characteristics of the hybrid were intermediate in respect to the parents. The chromosome number was counted in the root-tip cells as 2n=21. The meiotic behavior of the chromosomes was not studied in detail as the anthers degenerated, but a few configurations at first metaphase in which 2 or 3 bivalents and many univalents occurred were observed. The stigmas of the hybrid were dusted with pollen grains of Ae. triaristata and Ae. comosa with negative results, namely, no seeds were obtained from 204 pollinated florets. The cause of the complete sterility of the hybrid may be attributed to the degeneration of the embryo-sacs. From the following cross combinations carried out at the same time, 68 seeds were obtained from 386 florets, the success being 17.62%, but there were some seeds which did not germinate (Table 1). |