不同光照强度对芸豆光合特性及产量性状的影响

在100%自然光照(CK)、75.7%自然光照、50.3%自然光照、24.5%自然光照4种光照条件下,研究不同光照强度对芸豆光合特性、产量性状及产量的影响.结果表明,植株叶片叶绿素含量(Chl)在遮光后短期内有所增加,但长时间遮光后,含量会显著下降;在一定光照强度范围内,植株叶片叶绿素含量(Chl)、净光合速率(Pn)、气孔导度(Gs)和蒸腾速率(Tr)随光照强度的增加而增大,胞间CO2摩尔分数(Ci)则随之减小;遮光使芸豆开花数减少,单株结荚数、单株实粒数及粒质量显著或极显著下降,并随遮光强度的增强而受影响程度加大.同时各器官光合生产量也显著下降,尤其对荚果生长影响最大,75.7%、50.3%和24.5%自然光照条件下的单株经济产量分别比对照下降了43.2%、80.8 %和91.8 %,表明芸豆对光照强度要求较高.

Effects of Different Light Intensity on Photosynthetic Characteristic and Yield Characters of Kidney Bean

The photosynthetic characteristic, yield characters and yield were studied under four different light intensity treatments (100%,75.7%,50.3% and 24.5% sun-shading) of kidney bean.The results indicated that the chlorophyll content of leaves was increased in a short time after shading, but decreased under Long shading and was significantly lower than that of the controls.The chlorophyll content, photosynthetic rate, stomatal conduatance and transpiration rate of leaves were increased with increasing light intensity in a certain range of light intensity, but intercellular CO₂ concentration was decreased.The numbers of flowers of kidney bean were reduced under shading, especially the numbers of pods per plant, seeds per plant and seeds weight were significantly or very significantly decreased, and high shading level increased influence degree.The photosynthetic productions of different organs were significantly decreased after shading, especially the growth of pod.The economic yield per plant of 75.7%,50.3% and 24.5% sun-shading were decreased 43.2%,80.8% and 91.8% respectively.It seemed that kidney bean requires high light intensity.