光照强度对马齿苋生长及光合特性的影响

Studies on the Effect on Growth and Photosynthesis Characteristics of Purslane under Different Light Intensity

为明确光照强度对马齿苋生长发育、品质及光合特性的影响,采用人工遮光的方法,于马齿苋苗期进行遮荫,透光率分别为100%,(50±5)%和(25±5)%。分别测定了马齿苋的形态指标、生理指标及光合参数。结果表明:在100%透光条件下,马齿苋植株地上部和地下部干鲜质量、植株高度、可溶性蛋白、可溶性糖含量和叶绿素a/b值均与25%透光率条件存在显著性差异。马齿苋光饱和点和光补偿点分别为2 000μmol/(m2.s)和84μmol/(m2.s)。因此,马齿苋在营养生长期需要强光照,正常光照强度有利于马齿苋生长。马齿苋经遮荫处理后,光补偿点由84μmol/(m2.s)降至25μmol/(m2.s),说明其对光强具有较宽的适应性。

The study was carried out in order to explode the effects of shading on growth, development, quality and photosynthesis characteristics of purslanes under different light intensity. Four treatments were designed as light transmissivity of 100%, （50 ± 5）% and（25 ± 5）% respectively.The results showed that the purslanes which were under 100% light transmissivity growed faster than 25 % light transmissivity. As well as the FW and DW of overground parts and roots, the soluble sugar content, soluble protein content the value of chl a/b, there were significant difference with 100% light transmissivity. The light saturation point and light compensation point of purslane were 2 000 μmol/（ m^2 · s）and 84 μmol/（ m^2· s）. Therefore purslanes needed normal light intensity during vegetative growth phase, the normal light intensity was propitious to its growth and development. The light compensation point fell from 84 μmol/（ m^2 · s）to 25 μmol/（m^2· s）,so it had a wide adaptability to light intensity.