Breeding of wheat male sterile line with Aegilops crassa (6x) cytoplasm and research of its characters

Since Wilson and Ross （1962） bred wheat male sterile line with T. timopheevi cytoplasm （G type） and its relative restoration line, with high utilization value, the progress has been accelerated in research of heterotic use of wheat male sterility. But so far they have not been used in large area production, because of the limited restorer resource, imperfect grains and insignificant population heterosis. Ae（?）ilops kotschyi and Ae. Variabilis types/（Sv type） overcame well some problems in G type, such as restorer resource, grain plumpness etc., but at the same time, other more difficult problems arose, e. g. their sterile line and hybrid F1 generation produced monoploids at a certain rate, hybrid growth was weak and restorer degree of sterility had a large variation scale. The stability of sterility in Ae. Ventricosa （D type） and Ae unianstata （Mu type） cytoplasms, as well as the maintenance and restoration of their male sterile lines were further studied. In order