Comparison of Photosynthesis Characteristics of Leaves of Tetrastigma hemsleyanum in Different Cultivation Modes under Forest
Objective:To investigate the differences in the growth and photosynthetic characteristics of Tetrastigma hemsleyanum in different cultivation modes under forest.Methods:Two modes of annual clover planting were set up,i.e.in-ground planting and bag planting,and the relevant indexes of the growth and photosynthetic characteristics of clover vine and leaves were determined under different cul-tivation modes.Results:The main agronomic traits of T.hemsleyanum planted in bags under the forest were better than those planted in the ground under the forest.The length of the main stem was 3.04 times longer than that of the in-ground planting,and the number of nodes was 2.09 times longer than that of the in-ground planting.The SPAD value and nitrogen content of leaves in the bag planting mode were significantly higher than that of the in-ground planting mode.The trends of photosynthetic index-es were different between the two modes,and the indexes such as the net photosynthetic rate of leaves,the instantaneous water utilization,the photosynthesized effective irradiation and the foliar temperature of leaves in the bag planting mode were significantly higher than that of the in-ground planting mode.The correlation analysis of each index showed that the net photosynthetic rate of T.hemsleyanum was significantly positively correlated with the leaf surface temperature.The photosynthetically active radia-tion was very significantly positively correlated with the SPAD value and the nitrogen content of leaves,significantly positively correlated with the leaf surface temperature,while significantly nega-tively correlated with the length of the main stem and the number of nodes.Conclusion:The growth and photosynthetic performance of T.hemsleyanum in bag planting mode under the forest was signifi-cantly better than that of in-ground planting under the forest,which could provide a reference for the planting mode of T.hemsleyanum in artificial cultivation.