| Cytoplasmic-genic type of male sterility in Secale
montanum Guss. M. LAPINSKI Department of Plant Breeding and Seed Production, Agricultural University, Szczecin, Poland Introduction The possibilities for efficient utilization of hybrid vigor in cultivated rye have long time been considered to be limited because of lack of feasible cytoplasmic-genic male sterility system. At least one well documented case of cytoplasmic male sterility influenced in its expression by nuclear genes has been reported in past (PUTT 1954). But this source has eventually been lost. More recently some suggestive evidence of cytoplasmic-genic interaction for male sterility in cultivated rye has been presented independently by ZDRILKO (1969) and GEIGER and SCHNELL (1970). The purpose of this paper is to report the development of male sterility controlled by cytoplasmic-genic interaction in wild mountain rye. Material and method Secale cereale,cv. Smolickie and perennial Secale mottanum, KH66-30 were chosen as parental stocks to be used in a systematic search for cytoplasmic male sterility. Pollination with bulk pollen was practiced during the course of crossing and subsequent backcrossing of these two stocks. All other crosses reported in this paper were made between individual clones. Plants were scored for male sterility-male fertility expression on the basis of both visual inspection of spikes at the time of anthesis and microscopic examination of squashed anthers. Those plants having thin indehiscent anthers containing unstainable, if any, pollen grains were classified male sterile. Plants with dehiscing anthers, irrespectively of the amount of fertile pollen grains shed, were considered to be male fertile. Results and discussion In 1966, Smolickie rye cultivar was crossed reciprocally with wild strain KH66-30. Each of the two F1's was then crossed back twice to the male parent of the original cross giving rise to the substitution Bc2 families, Smolickie x KH66-303 and KH66-30 x Smolickie3. Plants bf these Bc2 families resembled quite closely the recurrent parents. The Bc2, KH66-30 x Smolickie3 plants appeared to be uniformly male and female fertile. Six of the 7 Bc2, Smolickie x KH66-303 plants were completely pollen sterile but set seed freely and I plant was fully fertile. The male fertile plant and one of the male steriles, hereafter referred to as MF 70/7-1 and MS 70/8-1 respectively, were chosen to establish clones for further studies. |
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