Effect Of Rainfall Harvesting Planting Technology Combined With Water-Saving Irrigation On Growth And Physiological Characteristics Of Summer Maize

Field experiment (using summer maize as an indicator crop) was conducted in the Farming Station of the Northwest A&F University (108°04’E,34°20’N) during2011-2012.Taking the furrow irrigation and border irrigation as control, the2-year field study in Guanzhong irrigation area was conducted to determine the effects of rainfall harvesting planting combined with water-saving irrigation (RHWI) on the growth, functional leaves photosynthetic and physiological characters and the economic yield of summer maize. The main conclusions of the study were as follows:1. The plant height, stem diameter, leaf area and dry matter weight under RHWI treatment after maize harvested were significantly higher than the treatments of furrow irrigation and border irrigation. Compared to furrow irrigation, border irrigation and RHP, the dry matter weight under RHWI after maize harvested was increased by18.5%,24.4%and6.4%in the treatment which irrigated1time at pre-sowing stage, by19.9%,25.1%and11.5%in the treatment which irrigated1time at flowering stage, and by14.4%,26.9%and11.5%of the treatment which irrigated1time at both pre-sowing and flowering stage.2. RHWI treatment could improve the photosynthetic capacity of summer maize at different degrees. Among the treatments with same irrigation period, the chlorophyll content, maximum fluorescence (Fm), variable fluorescence (Fv), maximal PS II efficiency (Fv/Fm) and PS II potential activity (Fv/Fo) of RHWI treatments were significantly higher than that of furrow irrigation and border irrigation. In RHWI, the net photosynthetic rate (Pn), the instantaneous water use efficiency (WUE) and Stomatal conductance (Gs) at filling stage were significantly higher than border irrigation. However, there was no significant effect on the minimal fluorescence (Fo) and transpiration rate (Tr) at the filling stage among the three irrigation treatments.3. The RHWI treatment could alleviate drought stress of summer maize. The MDA content of RHWI treatment was significantly lower than that of furrow irrigation, border irrigation and RHP. Simultaneously, SOD and POD activity of RHWI treatment were higher than these of furrow irrigation, border irrigation and RHP, thereby reducing the level of lipid peroxidation of Mesophyll cells.4. The RHWI treatment could improve the economic yield of summer maize. Compared with the furrow irrigation, border irrigation and RHP, the economic yield of RHWI treatment under irrigated1time at the pre-sowing stage was increased by4.9%(p<0.05),8.5%(p<0.05) and2.2%(p<0.05), by6.0%(p<0.05),8.3%(p<0.05) and1.3%under irrigated1time at flowering stage, and by7.0%(p<0.05),11.2%(p<0.05) and7.2%(p<0.05) of the treatment which irrigated1time at both pre-sowing and flowering stage. The WUEY of RHWI was significantly higher than that of furrow irrigation, border irrigation, and slightly lower than RHP treatment. The RHWI treatmen mainly by increasing ear length, ear diameter and Hundred-kernel weight to increase production...