%A YANG Chuan-Bang,YU Zhen-Wen,ZHANG Yong-Li*,SHI Yu %T Effect of Soil Depth with Supplemental Irrigation on Canopy Photosynthetically Active Radiation Interception andChlorophyll Fluorescence Parameters in Jimai 22 %0 Journal Article %D 2017 %J Acta Agronomica Sinica %R 10.3724/SP.J.1006.2017.00253 %P 253-262 %V 43 %N 02 %U {https://zwxb.chinacrops.org/CN/abstract/article_6238.shtml} %8 2017-02-12 %X

Supplemental irrigation based on moisture measurement of soil is a water-saving technology newly developed in wheat cultivation,in which soil depth is one of the key factors. In this study, we conducted a field experiment with the high-yield variety Jimai 22 in Yanzhou, Shandong province in 2013–2014 and 2014–2015 winter wheat seasons to unravel the photosynthetic basis of high yield by supplemental irrigation in the proper soil layer. Four supplemental irrigation treatments (relative soil water content of 70% and 75% at jointing and anthesis stage, respectively) were designed with the target soil depths of 20 (T20, 40 (T40), 60 (T60), and 80 cm (T80), and no irrigation and traditionally fixed irrigation (60 mm at jointing and anthesis each) were used as the controls. The indices measured were canopy photosynthetically active radiation(PAR) interception, canopy apparent photosynthesis(CAP), and chlorophyll fluorescence parametersof flag leaves from 0 to 30 days after anthesis, as well as grain yield and water use efficiency(WUE). The leaf area index, PAR interception, canopy light interception rate, CAP of treatment T40 were 6.0–42.4%, 8.5–27.9%, 6.7–14.5%, and 11.0–14.6% higher than those of treatment T20,respectively.At the same time, the maximal quantum yield of PSII (Fv/Fm), actual efficiency of PSII (ΦPSII) of flag leaves also improved significantly. When making supplemental irrigation to 60cm and 80cm soil layers, the above parameters had no significant increase. The grain yield of treatment T40 was not significantly different from that of T60,T80 andfixed irrigation control. However, irrigation amount significantly decreased by 26.9–46.9mm, water use efficiency and irrigation benefit significantly increased by 16.2–16.7% and 34.0–68.1% respectively during both wheat growing seasons as compared with those of fixed irrigation control. Supplemental irrigation based on soil moisture measurement in 0–40 cm soil layer is the most appropriate treatment in similar ecological conditions to this study for Jimai 22wheat cultivar.