通过花药培养筛选水稻耐镉突变体

通过花药培养筛选出三个水稻耐镉突变体并都获得再生植株。再生植株及由根尖诱导产生的愈伤组织都保持稳定的耐镉性。突变植株的花药经再培养鉴定也具有耐镉性,从而表明所获突变体的耐镉特性是可以遗传的。在对愈伤组织耐镉机理进行的分析中发现,突变体愈伤组织中的胱氨酸和半胱氨酸的含量高于对照。将一定量的胱氨酸加到含镉的培养基中用于检查野生型愈伤组织的增殖情况,观察到胱氨酸可以降低镉对细胞的危害,表明突变体耐镉机理可能与细胞中积累有较多的胱氨酸和半胱氨酸有关。

Selection of Cadmium Tolerant Mutants from Rice Anther Culture

Rice anthers with microspores at uninucleate stage were inoculated on the medium contain-ing200 mg/1 CdCl?Three call! were selected and differentiated into plantlets.The plantlets were tested for Cd tolerance under water culture with Cd concentration at 50 mg/1.After two weeks mutant plants could continue to grow while the growth of control was strongly stunted.The calli induced from roots of regenerated plants retained Cd tolerance when they were transferred to medium containing 200 mg/1 CdCl2.The anthers from mutant plants were inoculated on Cd medium.They still retained Cd tolerance.Cd and Zn contents inside calli cells of both mutants and control were determined.The result showed that there was no difference in Cd and Zn contents between mutants and control.Cystine and cysteine contents of the calli were determined,and it showed that cystine and cysteine were nearly twice as high in the mutant as that in the control on Cd-free medium and were three times higher on Cd 100 mg/1 medium.The detoxification efficiency of cystine on Cd toxicity to calli was confirmed by adding cystine to medium containing cadmium.