Effects of Different Light Intensities on the Main Physiological Characteristics of Buckwheat

[Objective] The purpose was to study the effects of different light intensity on buckwheat.[Method] With buckwheat after seeding emergence for 19 d as the tested material,3 shading treatments with the light intensity of 80%,60% and 40% of nature light were sep up to treat on the buckwheat seedlings,with light intensity of 100% as CK.After the shading treatments for 5 d,the leaf chlorophyll contents index,the net photosynthetic rates and the flavone contents in stem-leaves and seeds of the buckwheat during different growth stages were measured,and they were analyzed and compared by SSR.[Result] The chlorophyll exponent of buckwheat leaves was reduced with the increase of light intensity in short time after shading treatments and it was weaken with the reduction of light intensity.The stronger the light intensity was,the higher the net photosynthetic rate in leaves and the flavone content in stem-leaves were in squaring,blooming and bearing and mature stages.Their performance for different shading treatments in order was CK 80% light intensity 60% light intensity 40% light intensity.The flavone content in seeds of buckwheat had consistent change like this in mature stage.[Conclusion] The light intensity had greater effect on the leaf chlorophyll exponent,net photosynthetic rate and flavone content in buckwheat