泾惠渠灌区夏玉米非充分灌溉制度分析

Insufficient Irrigation Schedule for Summer Corn in Jinghuiqu Irrigation Area

干旱缺水是一个世界性问题,为了节约灌溉用水,提高水分利用效率,增加产量,研究水分亏缺对夏玉米的影响从而制定合理的灌溉制度有重要意义。2013-2016年,陕西泾惠渠灌区连续4年进行了夏玉米非充分灌溉试验,试验设置了8个非充分灌水处理,每个处理重复两次。试验结果表明:压茬期+灌浆期的株高显著低于其他处理8.4%,压茬期+拔节期的株高达到了最大值,拔节期的株高显著高于其他处理5%,拔节期未灌水处理的茎粗显著低于其他处理5.1%,抽雄期的产量显著高于其他处理6.98%,而3次灌水处理的水分利用效率最低。结论表明:非充分灌溉下,夏玉米压茬期和拔节期的灌水对于株高的影响很大;拔节期和苗期的灌水对于夏玉米茎粗的生长起到决定性的作用,而其他时期灌水对夏玉米茎粗的影响很小;拔节期和抽雄期是夏玉米产量的关键需水期;在夏玉米生育期的需水敏感期适度灌水是提高水分利用效率的有效途径,75%枯水年(2013-2016年)最优灌溉制度是:压茬期+拔节期+抽雄期,全生育期灌水3次,灌溉定额3 300 m3/hm2,该试验结果与当地夏玉米灌溉制度相比更为合理,节约灌水量27%。对泾惠渠灌区夏玉米非充分灌溉制度推广,提高水资源利用效率,缓解用水紧张的局面有着重大意义。

Drought is a worldwide problem. In order to save irrigation water and increase water use efficiency and increase yield,it is significant to research the effect of water deficit on summer corn. The insufficient irrigation experiment of summer corn had been continuously conducted in Jinghuiqu irrigation district for 4 years from 2013 to 2016. The experiment set 8 insufficient irrigation treatments and each treatment was repeated two times. The results show that： the plant height under the treatment of stubble pressing period and filling period is significantly lower than that of the other treatments by 8. 4%,while the height under the treatment of stubble pressing and jointing period reaches the highest,the plant height under the treatments of the jointing period is significantly higher than that of the other treatments by 5%,the stem diameter under the treatments of no irrigation in jointing stage is significantly lower than that of other treatments by 5.1%,the yield under the treatment of tasseling period irrigation is significantly higher than that of other treatments by 6.98% and the water use efficiency of the treatment of three times irrigation is the lowest. It can be concluded that： under insufficient irrigation,the irrigation of stubble pressing and jointing period has great influence on plant heights,the irrigation of seedling to jointing stage has decisive effect on the stem diameters growth of summer corn,while irrigation of other stages has small effects on summer corn stem diameters; the jointing and tasseling stage is the key water requirement period; moderate irrigation in the water sensitive period of summer corn growth period is an effective way to improve water use efficiency; the optimal irrigation schedule for dry year of 75% frequency（ 2013,2015 and 2016） is that： stubble pressing period adding jointing period and tasseling period,3 times irrigation during the whole growth period with the irrigation quota of 3 300 m3 per hectare.The experiment result is more reasonable than the local summer corn irrigation schedule and can save irrigation amount by 27%. It has great significance for promoting the insufficient irrigation schedule of summer corn in Jinghui irrigation area,improving the utilization efficiency of water resources and alleviating the situation of water shortage.