气候与矿质元素对柑桔叶片蒸腾作用的影响

EFFECTS OF THE ENVIRONMENTAL FACTORS AND MINERAL ELEMENTS-N,P,K,MG AND ZN ON THE TRANSPIRATION OF SWEET ORANGELEAVES(CITRUS SINENSIS OSBECK.CULTIVAR JINGCHEN)

锦橙叶片温度受气温和相对湿度的影响，但叶片的气扎阻力和蒸腾强度则由光照强度决定。阳面叶的蒸腾强度显著高于阴面叶。柑桔叶片气孔阻力与蒸腾强度呈双曲线负相关，阴、阳叶的模拟曲线不同，光量子数和气孔阻力与阳面叶的蒸腾强度间存在着交互作用，只有在一定的先量子数（＞３５０μｍｏｌ／ｓ．ｃｍ￣２）和气孔阻力（＜８ｓ／ｃｍ）阀值下，蒸腾强度才增加。施Ｍｇ可减小气孔阻力，提高蒸腾强度。Ｋ对蒸腾强度虽有削弱作用，但与适量的Ｎ，Ｚｎ配合后有助于蒸腾作用。叶片分析值表明，土壤供Ｋ特别是Ｋ，Ｍｇ同时施用对叶片中的Ｋ含量有显著作用。但叶片Ｋ，Ｍｇ含量与叶蒸腾强度及气孔阻力的相关性还有待研究。

Althoug the Jingchen orange(Cilrus sinensis Osbeck.)leaf temperature, which wasconsidered as one of the factors related to the transpiration , was mainly influenced by theatmosphere temperalure and relative humidity.The transpiration rate was particularly af-fected by bnth light intensity and the foliar stomatic resistance with the sun leaves possess-ing a higher ranspiration rate than shade leaves. Both the sun leaf and shade leaf showedtwo different negative hyperbolic forrelations between stomatic resistance and transpiration rate. Soil application per tree of urea(0～2 kg N),calcium superphosphate(0～1kgP_2O_5 )。 potash(0～1. 5 kg K_2O),magnesium sulfate (0～1.5 ks MgSO_4. 7H_2O) and zincsulfate (0～0. 4 kg ZnSO_4. 7H_2O)at different combinations showed certain effects on thetranspiration through a multiple quadratic regression model,in which, magnesium cotildremarkably reduce stomatic resistance and increase transpiration rate,otherwise, potassi-tim alone could diminish transpiration rate and stimulate it as it was appropriately com-bined with nitrogen or zinc. Furthernore,K content in the leaf was significantly influencedby the combination of these elements,especially K and Mg. There was not.however,anysignificant correlation hetween the foliar nutration and transpiration rate or stomatic resis-tance.