Effects of supplemental irrigation based on soil water content on water consumption, dry matter and yield of wheat

Yongli Zhang1, Zhenwen Yu1*, Yu Shi1, Shubo Gu1, and Yanyan Zhang1, 2
Water-saving cultivation in wheat (Triticum aestivum L.) is an important technique for achieving high yield and high water use efficiency (WUE) in the North China Plain (NCP) where water resources are in shortage. In order to determine the effects of supplemental irrigation based on soil water content on crop evapotranspiration (ET), DM, grain yield and WUE in wheat, treatments were designed to vary the relative soil water content at jointing and anthesis stages: I70 (70%, 70%) and I75 (75%, 75%) with rain-fed (I0) and traditional irrigation (Ick) as contrasts. The results indicated that the irrigation amount of I70 and I75 were significantly lower than that of Ick by 45.1 to 132.4 mm, but soil water depletion increased by 23.5 to 35.4 mm. Although the total ET throughout the growing season (ETt) of I75 was less than that of Ick, the ratio to ETt from anthesis to maturity increased significantly. The DM partitioning ratio was decreased in vegetable organs, but increased in grain for I75 compared with Ick. The grain yield for I75 was significantly higher than that of I0 and I70, whereas nonsignificant difference was observed between I75 and Ick, and the WUE and irrigation water use efficiency of I75 were higher than those of Ick by 11.0% and 87.4% in 2008-2009 and 3.5% and 34.0% in 2009-2010. Thus, I75 can be developed as an optimal water-saving irrigation regimes in the NCP.
Keywords: Dry matter accumulation and partitioning, grain yield, Triticum aestivum, water consumption characterization, water use efficiency.
1Shandong Agricultural University, Agronomy College, Key Laboratory of Crop Ecophysiology and Cultivation, Ministry of Agriculture, Taian 271018, P.R. China.
*Corresponding author (sdauwheat@sina.cn).
2Tai’an Academy of Agriculture Sciences, Taian 271000, P.R. China.