苜蓿抗乙硫氨酸(ETH)变异体的初步筛选

Primary Culturgl Selection for Varianst to Ethionine-resistance of Alfalfa

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。

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. O5 ~ 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. OOmM 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.