Welcome to Chinese Journal of Applied Ecology! Today is Share:

Chinese Journal of Applied Ecology ›› 2016, Vol. 27 ›› Issue (7): 2264-2272.doi: 10.13287/j.1001-9332.201607.033

• Special Features for the 25 th National Symposium on Landscape Ecology • Previous Articles     Next Articles

Photosynthetic gas exchange and water utilization of flag leaf of spring wheat with bunch sowing and field plastic mulching below soil on semi-arid rain-fed area.

YANG Wen-xiong1*, LIU Na1, LIU Xiao-hua1, ZHANG Xue-ting1, WANG Shi-hong1, YUAN Jun-xiu1, ZHANG Xu-cheng2   

  1. 1Institute of Wheat, Gansu Academy of Agricultural Sciences, Lanzhou 730070, China;
    2Institute of Dryland Farming, Gansu Academy of Agricultural Sciences, Lanzhou 730070, China
  • Received:2015-12-29 Published:2016-07-18
  • Contact: *E-mail: yang.w.x@263.net
  • Supported by:
    This work was supported by the Scientific Research Projects in the Public Welfare Industry of Ministry of Agriculture of China (201503125-01).

PDF (PC)

15

Abstract: Based on the field experiment which was conducted in Dingxi County of Gansu Province, and involved in the three treatments: (1) plastic mulching on entire land with soil coverage and bunching (PMS), (2) plastic mulching on entire land and bunching (PM), and (3) direct bunching without mulching (CK). The parameters of SPAD values, chlorophyll fluorescence parameters, photosynthetic gas exchange parameters, as well as leaf area index (LAI), yield, evapotranspiration, and water use efficiency in flag leaves of spring wheat were recorded and analyzed from 2012 to 2013 continuously. The results showed that SPAD values of wheat flag leaves increased in PMS by 10.0%-21.5% and 3.2%-21.6% compared to PM and CK in post-flowering stage, respectively. The maximum photochemical efficiency (Fv/Fm) , actual photochemical efficiency (ΦPSⅡ) of photosystem Ⅱ (PSⅡ), and photochemical quenching coefficient (qP) of PMS were higher than those of PM and CK, the maximum increment values were 6.1%, 9.6% and 30.9% as compared with PM, and significant differences were observed in filling stage (P＜0.05). The values of qN in PMS were lowest among the three treatments, and it decreased significantly by 23.8% and 15.4% in heading stage in 2012 and 2013 respectively, as compared with PM. The stoma conductance (gs) of wheat flag leaves in PMS was higher than that of PM and CK, with significant difference being observed in filling stage, and it increased by 17.1% and 21.1% in 2012 and 2013 respectively, as compared with PM. The transpiration rate (Tr), net photosynthetic rate (Pn), and leaf instantaneous water use efficiency (WUEi) except heading stage in 2013 of PMS increased by 5.4%-16.7%, 11.2%-23.7%, and 5.6%-7.2%, respectively, as compared with PM, and significant difference of WUEi was observed in flowering stage in 2012. The leaf area index (LAI) of PMS was higher than that of PM and CK, especially, it differed significantly in seasonal drought of 2013. Consequently, the PMS increased the SPAD values in flag leaves of spring wheat, and the capacity of flag leaves for photo energy assimilation and photosynthetic gas exchange were enhanced, caused more photosynthetic energy flowing into photochemical process, as well as decreased the heat dissipation, resulted in the increment of Pn and WUEi. Based on the higher Pn and LAI, the yield and WUE of PMS increased.