N、P互作对烤烟碳氮代谢关键酶活性的影响

Effects of nitrogen and phosphorus interaction on enzyme activity in carbon and nitrogen metabolism

通过大田试验研究了氮磷互作对烤烟碳氮代谢关键酶活性和叶绿素含量的影响。结果表明:钾肥施用量一定的情况下,随着氮素水平的提高,烟叶硝酸还原酶活性在团棵期、旺长期呈上升趋势,转化酶活性下降时间前移,淀粉酶活性在中后期也增加,Chl含量在叶片生长前期升高速度加快。施磷量45～105 kg/hm2范围内增加团棵期NR活性;施磷量105 kg/hm2和135 kg/hm2对转化酶活性影响无显著差异;增加施磷量可以明显增加叶片中后期淀粉酶的活性;施氮量为60 kg/hm2水平下,施磷量45～105kg/hm2范围内提高Chl含量。总体来看,中氮水平能使碳氮代谢适时转化,满足优质烟叶的生长要求,氮用量为60 kg/hm2水平下,m(N):m(P2O5):m(K2O)=1:1.75:3.375的肥料配比相对有利于烤烟的生长发育。

Effects of nitrogen and phosphorus interaction on enzyme activity in carbon and nitrogen metabolism and the content of chlorophyll were studied by filed experiment.Results showed that with equal K fertilizer rate,the tendency of nitrate reductase（NR） activity declined at early and middle stage;the decline of invertase（INV） activity shifted to an earlier date;amylase activity increased at later stage and the chlorophyll content of tobacco leaves increased faster at earlier stage.The nitrate reductase（NR） activity increased at earlier stage under phosphorus application of 45-105 kg/hm2;the application of phosphorus at 105 kg/hm2 and 135 kg/hm2 had no effect on the invertase（INV） activity.Applying more phosphorus can greatly increase amylase activity at later stage.With nitrogen level of 60 kg/hm2,chlorophyll content increased at the application of phosphorus of 45-105 kg/hm2.In conclusion,mid level of nitrogen is inductive to carbon and nitrogen metabolism which can lead to high quality tobacco growth.With nitrogen level of 60 kg/hm2,tobacco grows better at N and P20 and K2O rate of 1∶1.75∶3.375.