Correlation between Pigment Content, Fluorescence Parameters and Spectral Parameters of Cotton Leaves in Different Light Environments

Objective The purpose of this study is to estimate leaf photosynthetic physiological indexes with fast speed and no damage by studying spectral parameters and the relationship between chlorophyll content,chlorophyll fluorescence parameters and spectral parameters in different growth stages of cotton in different light environments.MethodThe cotton (Xinluzao No.45) leaves at different developmental stages were treated with shading,the pigment content,fluorescence parameters and spectral reflectance were measured and the correlation analysis was carried out.Result Compared with the CK,the reflectance was increased at 550 nm,not significant at 680 nm and decreased at 780-1,100 nm in different growth stages of cotton leaves in different light environments.There were significant correlations between pigment content,fluorescence parameters and spectral parameters of cotton leaves.ConclusionRRed/RGreen can be used to estimate the changes of carotenoid content in different growth stages of cotton leaves in different light environments.PSSRa,PSSRb and mSR705 can be used to estimate the changes of the parameters associated with photochemical processes at different growth stages of cotton leaves in different light environments,for example Y (Ⅱ),qP and qL,while PRI can be used to estimate the changes of the parameters associated with non photochemical processes,for example NPQ,qN and Y (NPQ).