Abstract: The primary screening work of somatic variants which were resistant to ethionine (ETH) was conducted.The Trekl, a high-regenerating cell line, was used as the screening material in this test.After they were treated by γ-ray with 2、4and 6 KR respectively, the calli were trans-fered on the solid and in liquid screenig media which contained different concentrations of ETH.Through.subculturing the calli on/in the same medium for three months, the levels of sulfur-con-taining amino acids in ETH-resistant calli were increaed by 1.05 1.80 folds as much as those in CK calli.And it appeared that the SCAA concpntrations would be increased with the increasing of ETH concentrations within the range of 0.02 1.00mM ETH in medium.The plantlets derived from the ETH-resistant calli screened under 0.02 and 0.1 mM ETH levels were obtained.The concentrations of SCAA in the plantlets were 1.83 and 4-17 folds higher than these CK plantlets.The results indicated that it would be a possible breeding route to improve the alfalfa quality by in vitro somatic variant selection.

Key words: Ethionine, The concentrations of SCAA, Variant

摘要： 用高胚性细胞系Treki作为筛选材料,进行了抗乙硫氨酸(ETH)变异体的初步筛选。愈伤组织经2、4、6KRγ射线照射后,转到含不同浓度的ETH固体和液体选择培养基中,继代筛选三个月后,抗性愈伤组织中的含硫氨基酸量比对照提高1.05～1.84倍,并在0.02-1.0mMETH范围内表现出有随ETH浓度升高而逐渐提高的趋势。从0.02、0.01mMETH的抗性愈伤组织获得了一批再生植株.植株体内的含硫氨基酸量是对照的1.83和4.17倍。结果表明细胞水平的突变体筛选,有可能是一条改良苜蓿品质的育种途径。

关键词: 乙硫氨酸, 含硫氨基酸, 突变体