Two types of gametocidal chromosome of Aegilops sharonensis and Ae. longissima.

Abstract

Certain chromosomes of A. sharonensis (2n = 14, S1S1) and A. longissima (2n = 14, S1S1), wild species related to wheat (Triticum), are retained selectively in durum and common wheats by their gametocidal action, which is exerted exclusively on gametes lacking the Aegilops chromosome. Three of such gametocidal chromosomes from A. sharonensis and 2 from A. longissima, collected from different sources, were studied on their cytological features, homoeology and interrelation. One of the A. sharonensis and one of the A. longissima chromosomes had similar N-banding patterns, which resembled that of wheat chromosome 2B, and were homoeologous to the group 2 wheat chromosomes. The other gametocidal chromosomes, which had been proved or thought to be in homeologous group 4, had N-banding patterns relatively similar to wheat chromosome 4A; the 2 A. sharonensis chromosomes could not be distinguished by the N-banding. In double monosomic additions of common wheat with the gametocidal chromosomes of the same homeology, gametes carrying either or both of the alien chromosome became fertile, and in those with non-homoeologous gametocidal chromosomes, only the gametes carrying the alien chromosome of homeologous group 4 were functional. There were 2 types of gametocidal chromosomes each in A. sharonensis and A. longissima.