Study On Canopy Temperature And Physiological Characteristics Of Different Mungbean Genotypes

Through the study on canopy temperature and a series of physiological parameters of two mungbean varieties, An 9204 and Bao 942-34, the results showed that, in the location characterized by completely identical climatic, soil, and cultural conditions, during flowering and maturing period, there are significant differences between the two mungbean varieties. That is, Bao 942-34 has a constant higher canopy temperature, while An 9204, on the whole, has a lower canopy temperature, and it manifests the feature of 'cold tail'.There are obvious differences in plant exterior performance and internal physiological activities between the two varieties. The leaf function period of An 9204 is longer than that of Bao 942-34. The chlorophyll content, gross nitrogen content, protein nitrogen content and soluble protein content of An 9204, on the whole, are higher than those of Bao 942-34. And that MDA content of An 9204, on the whole, is lower than that of Bao 942-34. And An 9204 has superiority to Bao 942-34 in transpiration rate and net photosynthetic rate.From the facts of above, we can say that the metabolic activities of the variety, which has a lower canopy temperature, are more superior to that of higher canopy temperature variety. That is to say, the lower canopy temperature variety has a better capability of resisting bad weather conditions, and can maintain a stable yield.The observation of microtome sections showed that the distribution of palisade parenchyma and spongy parenchyma of An 9204 are more regular and compact than those of Bao 942-34.The results of two concessive years research, on the whole, are consistent, and the appearance of canopy temperature is stable. From which we can draw a initiatory conclusion that there exists different canopy temperature phenomenon among different mungbean genotypes. There is plenty of mungbean germ plasma in China, and they have significant differences. The breeding and application of lower canopy temperature mungean varieties by means of canopy temperature will benefit to the increasing of mungbean yield, and then promote the development of mungbean industry.