锰胁迫对甜菜幼苗光合色素含量及碳氮代谢相关酶活性的影响

研究了盆栽条件下土壤中锰（Mn）污染对甜菜叶片叶绿体色素含量和幼苗期碳、氮代谢相关酶活性的影响。结果表明,随着Mn含量的增加,叶绿素a＋b、a/b及类胡萝卜素值逐渐减小;叶片1,5-二磷酸核酮糖羧化酶（Rubisco）含量下降,蛋白水解酶活性升高;硝酸还原酶（NR）和谷氨酰胺合成酶（GS）活性呈先升后降的变化趋势,其中以0.8mmol/L处理12d的影响最大。品种间比较,甜单301的类胡萝卜素和Rubisco含量降幅均大于KWS9419,而NR和GS活性在两品种上都显示出低剂量刺激高剂量抑制的特点,且时间累加效应明显。甜单301对Mn污染的敏感性高于KWS9419,而KWS9419对高Mn毒害的耐受性优于甜单301。

Influence of Manganese Stress on Photosynthetic Pigment Content and Activity of Carbon and Nitrogen Metabolism Related Enzyme

Pot experiment was conducted to test the effect of Mn pollution in soil on chlorophyll content and activity of carbon and nitrogen metabolism-related enzymes in sugarbeet seedlings.The results showed that with the increase of Mn content,Chla ＋ Chlb,Chla/Chlb and carotinoid content decreased gradually;rubisco content of leaf decreased,proteolytic enzyme activity increased;nitrate reductse（NR） and glutamine synthetase（GS） showed the trend at first rising and then falling,among them,there was the greatest change in treatment of 0.8 mmol/L 12 d.In species comparison,drop of carotinoid and rubisco content in TD301 were greater than that of KWS9419,the NR and GS activity in the two varieties have shown the characteristics of stimulation under low-dose and inhibition under high-dose,and the cumulative effect of time was significant.TD301 was more sensitive than KWS9419 to Mn pollution,while the tolerance to Mn toxicity of KWS9419 was higher than TD301.