‘温185’核桃根施氮磷钾肥的净光合速率效应

Effects of Root Fertilizing with Nitrogen, Phosphorus and Potassium on Foliar Net Photosynthetic Rate of Juglans regia‘Wen185'

通过肥料效应田间试验,检验中等土壤养分条件下‘温185’(Juglans regia‘Wen185’)核桃根施氮(N)、磷(P)、钾(K)肥的净光合速率效应,以期为新疆南疆盆地‘温185’核桃生产园的科学施肥管理提供参考。试验采用"3414"肥料效应田间试验与多元线性逐步回归分析相结合的方法。结果表明:‘温185’核桃净光合速率日均值(M)以10为底的常用对数(log_(10)M)同N肥的施用量(纯N量)和N肥施用量的自乘(N×N或N2)存在极显著(P<0.001)的线性相关关系,即:log_(10)M=0.724+0.231N-0.084N2+0.153P2。在土壤养分条件处于中等水平(有效P 14.0 mg/kg、速效K 77 mg/kg)的生产园,当N肥施用量(纯N量)小于2.75 kg/株时,对‘温185’核桃的净光合速率存在正效应,反之则存在负效应;施用P肥有利于提高‘温185’核桃的净光合速率。

Through fertilizer effect field trials, the study aims at testing the effect of root fertilizing with nitrogen（N）, phosphorus（P） and potassium（K） on the net photosynthetic rate（Pn） of J. regia‘Wen185＇under the medium soil nutrient condition, and provide a theoretical basis for scientific fertilization and management in walnut orchards. Both＂3414＂fertilizer effect field trial and the multiple linear stepwise regression analysis were used. The results showed that the denary logarithm（log_（10）M） of the daily mean value（M） of the net photosynthetic rate of J. regia‘Wen185＇had a highly significant linear correlation（P0.001） with the fertilizing amount of N fertilizer（pure amount of N） and its square（N×N or N^2）, the linear relationship was log_（10）M=0.724＋0.231N-0.084N2＋0.153P2. There was a positive effect of N fertilizer on the net photosynthetic rateof J. regia‘Wen185＇under the medium soil nutrient condition（available P 14.0 mg/kg, available K 77 mg/kg）in walnut orchards when the fertilizing amount of N fertilizer（pure N amount） was less than 2.75 kg per tree;otherwise the effect was negative. Meanwhile, the application of P fertilizer was helpful to improve the net photosynthetic rate of J. regia‘Wen185＇.