嫁接对烤烟氮代谢关键酶活性及叶绿素含量的影响

以金星6007为砧木,农大202为接穗,比较盆栽试验下不同施氮水平对烤烟嫁接苗和接穗自根苗的烟叶干质量、氮代谢关键酶(硝酸还原酶和谷氨酰胺合成酶)活性和叶绿素含量的影响。结果表明,烟叶干质量、硝酸还原酶活性、谷氨酰胺合成酶活性和叶绿素含量在两种氮水平下均为嫁接苗大于自根苗,且差异极显著。随着施氮量的降低和生育期的推进,嫁接苗和自根苗氮代谢关键酶活性和叶绿素含量都下降,但降幅不同,嫁接苗的降幅较低。以上结果说明,低氮水平下较高的硝酸还原酶活性、谷氨酰胺合成酶活性和叶绿素含量与烤烟嫁接苗的氮效率增强有关。

Effects of Grafting on Tobacco Key Enzyme Activities of Nitrogen Metabolism and the Contents of Chlorophyll

Using Jin Xing 6007 as rootstock and Nong Da 202 as scion,grafted plants were made to compare the differences in dry leaf weight,some key enzyme activities of nitrogen metabolism(nitrate reductase,glutamine synthetase)and the contents of chlorophyll between grafted and non-grafted tobacco seedlings grown in pot with the different amount of nitrogen.The results showed that nitrate reductase activities,glutamine synthetase activities and the contents of chlorophyll in leaves of grafted seedlings were significantly higher than those of non-grafted seedlings under two different amount of nitrogen.Nitrate reductase activities,glutamine synthetase activities and the contents of chlorophyll of grafted and non-grafted plants were decreasing with the decreasing nitrogen level,they were also decreasing when tobacco leaves were turning to mature.The speed of decreasing in grafted seedlings was slower than that in non-grafted seedlings.These results indicated that higher nitrate reductase activities,glutamine synthetase activities and the contents of chlorophyll might be resulted from the stronger nitrogen efficiency in grafted tobacco seedlings.