钾盈亏供应对黄瓜和番茄穴盘苗生长发育的影响

Effects of potassium excess or deficiency supplied on the growth and development of cucumber and tomato plug seedlings

以完全Hoagland营养液为对照,研究钾盈余供应(8倍钾浓度Hoagland营养液)和亏缺供应(1/8钾浓度Hoagland营养液)对黄瓜(‘中农203’)、番茄(‘中杂105’)穴盘苗形态建成、矿质元素和叶片叶绿素含量的影响。结果表明:对于黄瓜,钾盈余供给降低株高和叶绿素含量,抑制钙和镁的吸收,钾亏缺供给促进钙和镁的吸收。对于番茄,钾亏缺供给降低株高和茎粗,增大根冠比,促进钙、镁的吸收,钾盈余供给抑制钙和镁的吸收。以上结果说明,钾供应水平对穴盘苗生长至关重要,而且对不同蔬菜种类产生的影响也不同,因此,在生产过程中应根据蔬菜种类施入适量的钾肥。

In this study, the effects of potassium excess and deficiency supplied on the seedling morphogenesis, chlorophyll content and mineral content of tomato （Lycopersicon esculentum Mill. cv. Zhongza 105） and cucumber （Cucumis sativus L.cv. Zhongnong 203） plug seedlings were determined under the greenhouse conditions. The results showed that the plant height, chlorophyll content as well as calcium and magnesium concentration of cucumber plug seedlings decreased, but the content of calcium and magnesium increased when the supplied potassium is excessive. As for tomato plug seedlings, potassium deficiency decreased plant height and stem diameter, increased the ratio of root to shoot and the concentration of calcium and magnesium. On the other hand, potassium excess restrains the absorption of calcium and magnesium. Potassium was very important for the growth and development of cucumber and tomato plug seedlings. The effect of potassium on different species of vegetables is different. Therefore, we should apply the optimum potassium fertilizer according to the vegetables species in the production process.