快菜不同生长期对镉毒害的敏感性差异

Sensitivity of Brassica chinensis L. at Different Growth Stages to Cadmium Toxicity

以厚叶养生快菜为试材,采用水培的方法,研究了快菜种子萌发期和幼苗期对镉(Cd)毒害的敏感性差异。结果表明:50~400μmol·L-1 Cd胁迫对快菜种子发芽率、发芽势和发芽指数无明显抑制作用,但不同浓度Cd胁迫下快菜根长和活力指数显著下降。5~160μmol·L-1 Cd处理下快菜幼苗的总叶面积、地上部和地下部干质量和鲜质量均受到明显抑制。表明快菜幼苗期比萌发期对Cd毒害更敏感,其中快菜幼苗的根干质量对Cd胁迫的响应比其它指标更为敏感,其EC10、EC20和EC50值分别为0.03、0.26、13.03μmol·L-1,可作为快菜对Cd毒害敏感性的筛选指标。

Using Brassica chinensis L.cv Houyeyangsheng as the test material,the sensitive difference of cadmium toxicity between seed germination stage and seedling stage was studied by hydroponics.The results showed that 50-400μmol·L-1 Cd stress had no significant inhibitory effect on seed germination rate,germination potential and germination index,but the radicle length and vigor index of Brassica chinensis L.decreased significantly under different concentrations of Cd stress.The total leaf area,dry weight and fresh weight of shoots and roots of Brassica chinensis L.seedlings were significantly inhibited under 5-160μmol·L-1 Cd treatment.The results showed that Brassica chinensis L.at seedling stage was more sensitive to Cd toxicity than that at germination stage.Root dry weight of Brassica chinensis L.seedlings was more sensitive to Cd stress than other indicators,EC10,EC20 and EC50 values were 0.03,0.26,13.03μmol·L-1,which could be used as a screening index for sensitivity of Brassica chinensis L.to Cd toxicity.