灌溉春玉米大喇叭口期光合特性及水分利用效率研究

为了寻求在气候变化过程中保持作物产量不断增长，提高作物水分利用效率的地面灌溉节水与生物节水综合配套技术。通过分期播种和不同灌溉方式对大田春玉米进行试验，采用LI-6400便携式光合仪测定了石羊河流域灌溉区环境因子和春玉米大喇叭口期叶片光合生理指标和水分利用效率，分析了不同播期和不同灌溉方式对春玉米光合参数和水分利用效率的影响。结果表明：滴灌、喷灌和漫灌3种灌溉方式中滴灌最有利于提高春玉米叶片的净光合速率（提高10%~21%）、气孔导度（提高33%~43%）和作物水分利用效率（提高12%~20%）。方差分析表明，不同播期对春玉米叶片净光合速率、气孔导度和水分利用效率影响较小，但第二播期的净光合速率较第一、三播期提高10%~20%、蒸腾速率提高20%~28%、气孔导度提高20%~28%。通过显著性相关分析，空气温度、大气CO2浓度和光合有效辐射是影响滴灌叶片光合参数的主要环境因子，相关系数达0.810~0.986(P<0.05)。光合有效辐射和大气CO2浓度是影响喷灌叶片光合参数的主要环境因子，相关系数达0.850~0.980(P<0.05)。空气湿度、温度和大气CO2浓度是影响漫灌光合参数和水分利用效率的主要环境因子，相关系数达0.969~0.989(P<0.05)。滴灌也是最适宜于干旱区的抗旱、节水、节肥和增产的灌溉方式，3个播期中第二播期（4月20日“谷雨”前后）是当地最适宜于地膜春玉米播种的时期。

Study on the Photosynthetic Characteristics and Water Use Efficiency of Big Trumpet Period Spring Corn by Irrigating

In order to maintain crop yield increasing and improve water use efficiency of crops, the surface irrigation water-saving and biological water-saving of integrated technology were studied in the climate change process. The field spring corn was tested by stages’ sowing and different irrigation methods. The environmental factors and big trumpet period spring corn’s photosynthetic physiology indexes, water use efficiency were measured by LI-6400 portable photosynthesis system in Shiyang River Basin. The effect of different sowing stages and different irrigation methods were analyzed on photosynthetic parameters and water use efficiency of spring corn. The results showed that: drip irrigation could improve the spring corn leaves’ net photosynthetic rate (10%-21%), stomatal conductance (33%-43%) and water use efficiency (12%-20%) of drip irrigation, sprinkler irrigation and flood irrigation in the 3 irrigation methods. Analysis of variance showed that different sowing date effected corn leaf net photosynthetic rate, stomatal conductance and water use efficiency was small. But the second sowing date of net photosynthetic rate than the first and three sowing date increased by 10%-20%, transpiration rate increased by 20%-28%, stomatal conductance increased by 20%-28%. By analyzing significant correlation, that the air temperature, atmospheric CO2 concentration and photosynthetic active radiation which affected drip irrigation’s leaf photosynthetic parameters were major environmental factors, correlation coefficient of 0.810-0.986 (P<0.05). The photosynthetic active radiation and atmospheric CO2 concentration which affected sprinkler irrigation leaf photosynthetic parameters were major environmental factors, correlation coefficient of 0.850-0.980 (P<0.05). The air humidity, temperature and atmospheric CO2 concentration which affected flood irrigation’s photosynthetic parameters and water use efficiency were the main environmental factors, correlation coefficient of 0.969-0.989 (P<0.05). Drip irrigation was the most suitable for arid regions, which could combat drought, save water, save fertilizer and improve yield irrigation method. The second sowing date(April 20th "Guyu before and after") was the most suitable for spring corn sowing period of the three sowing dates.