Chlorophyll fluorescence and grain filling characteristic of wheat (Triticum aestivum L.) in response to nitrogen application level

Abstract

This study aims to understand the influence of chlorophyll fluorescence parameters on yield of winter wheat in some areas of China. Nitrogen (N) application is believed to improve photosynthesis in flag leaf ultimately increase final yield. To understand the response of chlorophyll fluorescence parameters ofwheat, flag leaf and the effect of N fertilization was carried out at booting stage under greenhouse during year2018-2019 using winter wheat cultivar "Yunhan-20410' 'Yunhan-618". The results showed that the maximumchlorophyll content of flag leaves occurred at booting stage. Under, Yunhan-20410 condition, maximumphotochemical quantum efficiency (FV/Fm), potential activity (ΦPSII), potential activity of PSII (FV/FO), andphotochemical quenching coefficient (qp) showed "high-low" variation, and the maximum values were observedbetween May 4 and May 12. However, Yunhan-20410 showed FV/Fm, FV/FO, and qp showed "low-high-low" curveat booting stage. Compared to Yunhan-618, Yunhan-20410 at booting stage significantly decreased FV/Fm,FV/FO, qp, and ΦPSII (P<0.05), and non-photochemical quenching (NPQ) significantly increased (P<0.05). The outcome of present investigation suggest that chlorophyll fluorescence parameters could bevaluable insight to understand yield stability under stress condition. Moreover, the investigated parameters could beuseful criteria for selection of genotypes under varying nitrogen application levels.