Light absorption and response characteristics of photosynthetic available radiation on photosynthesis of eggplant leaves under monocolour light quality

This paper studies the light absorption of leaves and chlorophyll and response characteristics of Pn/PAR with white light (400-700 nm) and mono-color light quality [red light(650±5)nm,blue light(470±5)nm],and analyses the photosynthetic efficiency of red light and blue on eggplant(Solanum melongena L.)'HEISHUAI' which adapted in greenhouse.The absorption value red light(660 nm) and blue light(470 nm) of chlorophyll in the scope of strong wavelength 400-480 nm and 650-680 nm are higher,the absorption value of white light(400-700 nm) are lower,the leaf's absorption coefficient e of red light through the LED light source measured by the integral ball is higher than that of white light,and the e of blue light is the lowest.The light saturation point(LSP) under three kinds of lights vary between 1 800-2 000 μmol/(m2·s),presenting no significant differences;on the other hand,the apparent quantum yield(AQY),the practical quantum yield(PQY),the maximum net photosynthetic rate(Pnmax) and the maximum light conversion efficiency(LCEmax) of blue light are lower than those of red light;while the light compensation point(LCP) and the light semi-saturation point (LSPsemi) of blue light are higher than those of red light.Results indicate that the photosynthesis efficiency of blue light is lower than the red in that the e of blue light is lower than red.