磷钾配施对晒红烟碳氮代谢和光合效率的影响

Effects of P and K Fertilizers on the Carbon and Nitrogen Metabolism and Photosynthetic Efficiency of Dark Sun-cured Tobacco

采用盆栽试验研究了磷钾配施对晒红烟碳氮代谢和光合效率的影响。结果表明,在氮用量相同的情况下,磷钾肥缺乏易导致硝酸还原酶(NR)活性、转化酶(INV)活性和叶绿素含量下降。在旺长期以前,不施磷肥和磷肥缺乏的处理NR/INV比值较大,不施磷钾肥和磷钾肥缺乏易导致Fv/Fo和Fv/Fm降低,并且磷素缺乏的影响程度要大于钾素缺乏的影响程度。在参试的5个处理中,以施用纯N 150 kg/hm2,N:P2O5:K2O=1:2:2.5的肥料配比有利于烟株的碳氮代谢平衡。

The effects of P and K fertilizers on the carbon and nitrogen metabolism and photosynthetic efficiency of dark sun-cured tobacco were studied with a pot experiment. The results showed that with equal N rate （150kg N per hectare）, the nitrate reductase （NR） activity, invertase （INV） activity, and chlorophyll contents of fresh leaves decreased without P or K fertilizer application. The NR/INV ratio was higher in case of no or low P appfication and the values of Fv/Fo and Fv/Fm decreased in either case of no or low P and K application. The effect of P deficiency was severer than K deficiency before fast growing stage. The application of N 150 kg/hm^2 with N：P2O5：K2O=1：2：2.5 was in favor of the balance of carbon and nitrogen metabofism.