缺磷条件下的小麦根系酸性磷酸酶活性研究

1　引　　言植物根可向根际分泌许多有机化合物 ,其中有许多物质都能促进植物对矿质养分的吸收 .作为必需大量营养元素的Ｐ ,在土壤中以无机磷酸盐阴离子的形式被吸收 ,而有机磷酸酯必须被水解成无机Ｐ后才能进入植物根 ,在这一过程中有一非常重要的步骤 ,就是由微生物、菌根外真菌和植物根分泌酸性磷酸酶 .土壤中的有机Ｐ一般占全Ｐ的 30 %～ 5 0 % ,有的可达95 % .因此 ,如何发挥植物自身利用土壤有机Ｐ的潜力已成为目前植物营养学研究的热点之一 .Ｇｏｌｄｓｔｅｉｎ等[3 ] 研究Ｐ胁迫条件下悬浮培养细胞时发现 ,抑制植物生长和诱导酸性…

Effect of phosphorus deficiency on activity of acid phosphatase exuded by wheat roots

The activity of acid phosphatase exuded by roots,the tissue location of the enzyme, and the relationship between the enzyme activity and phosphorus efficiency of wheat were studied. The results showed that the activity of acid phosphatase exuded by wheat 81(85)5 3 3 3 and NC37 under P sufficiency treat were lower than those under P deficiency, and the enzyme activity of the former variety was significantly higher than that of the latter. There was a significant difference in the enzyme activity among 12 wheat genotypes grown under P deficiency treat. Acid phosphatase was exuded by epidermis cell of root, especially by epidermal cell of root apex. Thus, there was a linear relationship between the enzyme activity and the surface area of root or the number of root apexes. It implied that the enzyme activity was markedly related to the size of root system. The linear relationship between relative grain yield and acid phosphatase activity was significant. It indicates that the enzyme activity could be used as an early indicator to select P efficient wheat genotypes.