土壤有效硅对黄瓜种子萌发和幼苗生长代谢的影响

Effect of Available Silicon in Soil on Cucumber Seed Germination and Seedling Growth Metabolism

利用盆栽试验研究土壤有效硅对黄瓜种子萌发和幼苗生长代谢的影响。结果表明 :土壤有效硅含量在 5 5 .1～ 2 0 2 .8mg·kg-1范围内 ,随含量的增高 ,种子萌发过程中蛋白酶和脂肪酶活性升高 ,呼吸速率加快 ,种子活力升高 ,萌发速度加快 ;幼苗生长过程中光合强度增强 ,根系活力、硝酸还原酶活力升高 ,蒸腾强度减弱 ,蒸腾比率和叶片含水量升高 ,说明土壤中的硅被黄瓜有效利用 ;土壤有效硅含量超过2 0 2 .8mg·kg-1时 ,其对黄瓜种子萌发和幼苗生长的促进作用不再显著增加。

Cucumber plants were cultured in flowerpot for the investigation of the effect of available silicon in soil on cucumber seed germination and seedling growth metabolism. The result showed that when the content of available silicon in soil was between 55.1 and 202.8 mg·kg -1, with the increase of available silicon in soil, the activities of protease and lipase during cucumber seed germination were promoted , the respiration rate of seedlings was accelerated, and seed vigor was increased; the photosynthesis rate, root activities and nitrate reductase activity of cucumber seedlings during seedlings growth were increased. The transpiration rate was decreased, while transpiration ratio and leaf water content were increased. From the facts above, it can be shown that silicon which was assimilated in soil improved nutrition metabolism of cucumber seed and seedling. As a result, seed germination and seedling growth rate were advanced. The investigation showed that the highest content of available silicon in soil which can increasingly promote seed germination and seedling growth rate was 202.8mg·kg -1.