|Chromosome pairing in the F1 hybrid plants
between Triticale No. 17 (8x) and Agrapyron glaucum (6x)
Faculty of Agriculture, Tottori University Tottori, Japan
From the cross of Triticale No. 17 (2n=56, AABBDDRR) with Agropyron glaucum ROEM. et SCHULT. (2n=42, BBEEFF? I/), two hybrid plants (2n=49) were obtained. It seems likely that no F1 hybrid plants with ABDRBEF genomes have been cytologically investigated before though there have been many reports of cytological observations on F1 hybrid plants between Ag. glaucnm and a species of Triticinae. Thus, meiotic behavior of the plants was studied. The chromosome configurations and their frequency at MI in PMC's of the F1 were summarized in the following table.
The number of conjugated chromosomes varies from 0 to 8 with mode of 5, and few cells of PMC's examined had a trivalent. Out of 68 cells, only one cell of the class with 511+391 had two ring-shaped bivalents besides rod-shaped bivalents and univalents, and all the rest cells had rod-shaped bivalents and univalents.
According to the previous workers, it is suggested that wheat within Dinkel group and Ag. glaucum have at least one genome, probably B genome, in common. However, from only the aforementioned result, it is impossible to know definitely whether those conjugated chromosomes were of B genome or not.
The hybrid plants were perennial, completely sterile and seemed to be less valuable as the breeding material for fodder plants. But, it is quite interest that the perennial, character of Ag. glaucum is epistatic to the annual of both wheat (ABD) and rye (R) even when they are together in a plant.
|I/ Suggested by Matsumura (1949)|