黄瓜单个叶片光合特性研究

Studies on Photosynthetic Characteristic of a Single Leaf of Cucumber

系统测定了１９个春季露地和冬季温室黄瓜壮龄叶片光合速率及其日变化，结果表明，在露地栽培条件下，大多数品种、杂交种和品系光合速率分布在ＣＯ２２０～３０μｍｏｌ·ｍ２·ｓ１之间。冬季温室栽培的长春密刺的光合速率远较露地栽培时低。无论温室还是露地栽培，黄瓜壮龄叶片光合速率日变化均呈双峰曲线型，有明显的“午休”现象。光照强度、ＣＯ２浓度、温度及土壤湿度等外界环境条件，以及黄瓜叶腋负载果实与否的内在因素对光合速率有明显影响，对光合速率日变化类型无影响。

Measurement of photosynthetic rate and its diurnal variation of a single adult cucumber leaf was carried out both in field in the summer and in greenhouse in the winter in 1991, and the photosynthetic rates of different cultivars, hybrids and lines grown in the field were compared with each other. Some factors affecting the photosynthesis were also discussed. The statistical result showed that photosynthetic rate of most cultivars, hybrids and lines ranged from CO2 20 to 30 μ mol· m(-2)· s(-1) and there was no significant difference among them. The photosynthetic rate of ' Changchun mici' in the greenhouse in the winter is lower than that in the field in the summer.The curve of photosynthetic diurnal variation of cucumber had two peaks, having an obvious midday depression in the case of 'Changchun mici' grown both in greenhouse and in field. Either enviromental factors such as intensity of light, CO2 concentration, temperature and relative moisture of soil, or interior factor such as the fruit in the axil exerted significant effects on photosynthetic rate except photosynthetic type of diurnal variation.