茶树钾营养特性的研究

Study on Nutritive Pecularity of Potassium in Tea Plant

本文对我国主要茶区茶园土壤的含钾状况、茶树品种和土壤水分对茶树吸收钾的影响和茶园施用钾肥的增产效果进行了系统研究。结果表明,我国有近60％的茶园土壤处于缺钾状态,这已成为限制茶叶高产优质的主要障碍因子之一。不同品种茶树对钾的吸收具有明显差异,它们对钾的最大离子吸收速率V_(max)为龙井43>碧云>苹云>碧峰>菊花春,米氏亲和常数K_m为碧峰>碧云>龙井43>苹云>菊花春。干旱处理的茶树体内累积的钾和叶片的含钾量明显高于水分适宜的处理,表明干旱能促进茶树对钾的吸收和从根部向地上部的运转。钾肥的增产效果受土壤有效钾水平及土壤有效氮和钾的比例的影响,当土壤有效钾含量超过80ppm时,只提高钾肥用量而不相应增加氮肥,则会降低钾肥的增产效果。

The content and distribution of potassium in tea garden soils in main tea-producing provinces of China, the effects of different tea varieties and soil moistures on K+ uptake by tea plant and the yield response of potassium fertilizer in tea fields were studied. The results showed that: (1) About 60% of total tea garden soil in China were deficient in available potassium content, which was one of the main facters resulting in low yield and poor quality of tea. (2) Potassium uptaken by tea plant of different varieties were significantly different. The maxium uptake rate, Vmax, ranged as follows Longjing 43 > Biyun > Pingyun > Bifeng > Juhuachun. (3) The amount of potassium cumulated in tea plant and leaves were increased under soil drought, indicating that uptake and translocation of potassium were promoted. (4) The efficiency of potassium fertilizer was influenced by the content of available potassium and the ratio of available N to K in tea garden soil. When available potassium content surpassed 80 ppm, the effect of potassium on yield could get lower without increasing N / K ratio.