玉米高温热害预防与缓解技术探讨

Prevention and Mitigation Technology of Heat Damage in Corn

以玉米(Zea mays L.)蠡玉16号为试验材料,设置5个不同时期进行播种,研究了高温干旱情况下不同播种时期对玉米农艺性状、经济性状和产量的影响;并通过在6月14日播种的另外小区里设置5个不同处理(浇水抗旱、辅助授粉、拔去雄穗、折断叶片、割去茎叶),研究了不同处理对玉米高温热害的缓解作用。结果表明,异常高温干旱气候条件下,不同播种期的玉米均受到了不同程度的危害,且播期越迟,危害越重,江汉平原的玉米播种期应安排在5月底以前,视茬口情况越早越好。且当玉米遇高温干旱时,采取浇水抗旱、人工辅助授粉、折断果穗上部一片叶等措施,可以降温增湿,有利授粉,减少秃穗率,提高结实率,增加产量,缓解高温热害危害,其中浇水抗旱措施增产13.5%,效果最为显著。

Corn variety Liyu 16 was used as material to study the effects of different sowing time on agronomic traits,economic traits and yield of corn under high temperature and drought conditions by setting 5 different sowing dates,and to study the mitigation effect of different treatments on heat injury of corn by setting up 5 different treatments（irrigation,artificial pollination,removing tassel,breaking leaves,cutting the cauline leaves） in another experiment sown on June 14.The results showed that in the case of abnormal high temperature and dry climate,corn with different sowing dates was affected to different degrees,and the later the sowing date,the more severe the harm.The sowing time of corn in Jianghan plain should be arranged before the end of May,and the sowing time should be as early as possible.When in high temperature and drought situation,irrigation,artificial pollination,breaking a leaf in the upper part of the ear and other measures could reduce temperature,increase humidity and promote pollination,which would be good for reducing bald rate,increasing seed setting rate,increasing production and reducing heat damage.Among those measures,irrigation was the best in increasing yield,with a yield increase of 13.5%.