不同浓度碳酸氢钾对黄瓜幼苗光合作用的影响

Influence of KHCO_3 on the Cucumber Sprout and Photosynthesis

研究了不同浓度碳酸氢钾(KHCO3)对黄瓜幼苗光合作用的影响。结果表明,对黄瓜幼苗叶面喷施KHCO3可以显著提高其光合速率,且气孔导度、光饱和点、表观量子效率、羧化效率均得到了不同程度的提高,而光补偿点、CO2补偿点则有所下降,同时光合关键酶核酮糖-1,5-二磷酸羧化酶的活性也得到了促进。笔者还发现在黄瓜幼苗叶片中存在C4途径的关键酶磷酸烯醇式丙酮酸羧化酶,同时KHCO3可提高该酶的活性。浓度为1 500 mg/L的KHCO3对黄瓜幼苗光合作用的促进效果最理想。

The influence of different consistency KHCO3on cucumber seedling photosynthesis was studied in this text. The results showed that KHCO3 can notably raise photosynthetic rate of cucumber seedling. And at the same time it can also raise stomatal frequency light saturation point AQY and CE but the light compensatian point and CO2 compensation point descend to some extent and the activity of photosynthetic key enzyme-RuBP carboxyla se was promoted. We also found the PEPC that exists in C4＇s path in leaf of the cucumber seedling and KHCO3 can raise the active of this enzyme. By way of the tests when KHCO3＇s consistency was 1500 mg/L it was most ideal to promote photosynthesis of cucumber seedling.