覆膜与滴灌对东北春玉米产量及水氮利用效率的调控效应研究

发布时间：2018-05-31 03:27

本文选题：春玉米 + 干旱　；参考：《中国农业大学》2015年博士论文

【摘要】：东北是我国重要的玉米产区,该地区降水时空分布不均,年际及年内变率大,旱灾频发。因此,研究覆膜和滴灌等抗旱措施对玉米产量和水氮利用的影响,探讨东北地区玉米高产与资源高效利用的栽培技术体系,是保障我国粮食安全和资源环境安全的迫切需求。本研究通过田间试验,比较分析了不同降雨年型覆膜对玉米产量和水分利用效率的影响及其机理,探讨了覆膜条件下不同密度玉米的产量响应,同时研究了不同滴灌方式对产量和水氮利用效率的影响,取得的主要研究结果如下： 1.通过对4年5点覆膜玉米产量反应及机理分析,发现在干旱年份下覆膜提高玉米产量15%～26%,多雨年份下覆膜无明显增产作用。干早年份下覆膜增产的机理是显著提高了生育前期耕层土壤含水量和土壤温度,提高了花前干物积累量和积累速率,从而显著增加了收获期总干物质,最终提高产量和水分利用效率。在多雨年份下,受阴雨寡照影响,覆膜仅显著提高拔节前土壤温度和土壤含水量,花前和花后干物质总量差异不显著,从而产量和水分利用效率无显著差异。 2.通过研究覆膜对不同密度春玉米的影响,发现覆膜和雨养玉米中密度(67500株hm-2)和高密度(90000株hm-2)处理产量都显著高于低密度(45000株hm-2),分别高7.4%、7.1%和5.8%、6.2%,中高密度之间产量差异不显著。与低密度相比,中、高密度处理增产主要是显著提高了亩穗数(平均高21.6%)和成熟期干物质积累量(平均高19.6%),中密度和高密度处理间产量差异不显著。与高密度相比,中密度虽然亩穗数较低,但由于保证了较高的弱势粒灌浆速率,改善了群体根系的分布,提高了根冠比,从而也获得了较高的产量水平。 3.通过研究3种滴灌管(传统和新型)及3个埋管深度(0、5、10cm)对玉米生长发育及产量的影响,发现新型滴灌管在重力滴灌时保持较高的流速,与雨养玉米相比,滴灌处理显著增产9.5%～20.1%,其中新型滴灌埋深5cm增产幅度最大(20.1%),较相同埋深传统滴灌增产8.8%。新型滴灌埋深5cm产量高于其他处理的原因是生殖生长期叶面积指数下降慢,显著提高收获期干物质重。同时提高了水分利用效率。 4.通过研究4个滴灌量(120%ET、100%ET、80%ET、60%ET)和3个施氮量(N90、N180、N360)互作对玉米生产的影响,发现滴灌80%ET处理,施氮量为180kg hm-2时,玉米产量及水氮利用效率与正常灌水(100%ET)处理无显著差异,说明滴灌在节水20%时仍可以取得较高经济效益。 5.通过研究不同密度下3种灌溉方式：雨养、漫灌、滴灌对玉米生产的影响,发现各密度下雨养玉米产量最低。中(67500株hm-2)、低(45000株hm-2)密度时滴灌和漫灌处理产量差异不显著。在高密度(90000株hm-2)时滴灌处理较漫灌处理增产6.7%。因为滴灌处理在高密度下可获得较高的叶面积指数、总干物质积累量和氮素积累量,并显著提高水氮利用效率。
[Abstract]:Northeast China is an important corn growing area in China. Rainfall in this area is unevenly distributed in time and space, with high annual and annual variability and frequent drought. Therefore, it is an urgent need to study the effects of mulching and drip irrigation on maize yield and water and nitrogen utilization, and to explore the cultivation technique system of high yield and high efficiency utilization of maize resources in Northeast China. In this study, the effect and mechanism of different rainfall year film mulching on maize yield and water use efficiency were compared and analyzed by field experiment, and the yield response of maize with different density under film mulching was discussed. At the same time, the effects of different drip irrigation methods on yield and water and nitrogen use efficiency were studied. The main results were as follows: 1. Based on the analysis of yield response and mechanism of film mulching maize in 4 years, it was found that film mulching could increase maize yield by 15% and 26% in drought year, but film mulching had no obvious effect on increasing yield in rainy year. The mechanism of film mulching in early dry years was to increase the soil moisture content and soil temperature, increase the accumulation and accumulation rate of dry matter before anthesis, and increase the total dry matter at harvest stage. Finally, the yield and water use efficiency will be improved. In rainy years, film mulching only significantly increased soil temperature and soil water content before jointing, but there was no significant difference in total dry matter before and after anthesis, so there was no significant difference in yield and water use efficiency. 2. The effects of film mulching on spring maize with different densities were studied. It was found that the yield of the treatments treated with film mulching and rain-fed maize with medium density of 67500 plants and high density of 90000 plants was significantly higher than that of low density maize of 45000 plants, and the yields of medium and high density maize were 7.41% and 5.8%, respectively. There was no significant difference in yield between medium and high density corn. Compared with low density, the increase of yield of medium and high density treatments was mainly due to the significant increase in the number of ears per mu (with an average of 21.6kum) and the accumulation of dry matter in maturing stage (an average of 19.6cm). There was no significant difference in yield between medium density and high density treatments. Compared with high density, although the number of panicles per mu was lower in medium density, the higher grain filling rate of inferior grains was ensured, the distribution of root system was improved, the ratio of root to shoot was increased, and a higher yield level was obtained. 3. By studying the effects of three kinds of drip irrigation pipes (traditional and new) and three kinds of buried pipes (0 ~ 5 ~ 5 ~ 10 cm) on the growth and yield of maize, it was found that the new type of drip irrigation pipe maintained a high velocity of flow in gravity drip irrigation, and compared with that of rainfed corn. The yield of drip irrigation increased significantly by 9.5% ~ 20.1g / L, and the yield of new type drip irrigation was the largest (20.1g / L) than that of traditional drip irrigation (5cm), which was 8.8g / L higher than that of traditional drip irrigation with the same buried depth. The 5cm yield of the new type of drip irrigation was higher than that of other treatments because the leaf area index decreased slowly and the dry matter weight increased significantly during the harvest period. At the same time, water use efficiency was improved. 4. Through the study of the effects of the interaction of four drip irrigation quantity (Tet 120) on maize production, it was found that there was no significant difference in maize yield and water and nitrogen use efficiency between drip irrigation 80%ET treatment and normal irrigated water 100th et treatment with four drip irrigation amount of et 100 and three N application rates N90 + N180 and N360), and the results showed that there was no significant difference in maize yield and water nitrogen use efficiency between drip irrigation 80%ET treatment and normal irrigation 100 et treatment. It shows that drip irrigation can still achieve high economic benefit when saving water for 20 years. 5. The effects of three irrigation methods on maize production under different densities: rain irrigation, diffuse irrigation and drip irrigation were studied. It was found that the yield of maize fed with rain was the lowest at different densities. There was no significant difference in yield between drip irrigation and diffuse irrigation at the density of 67500 strains of hm-2 and 45000 strains of hm-2). The yield of drip irrigation was 6.7% higher than that of diffuse irrigation at high density of 90000 plants (hm-2). Under high density, drip irrigation could obtain higher leaf area index, total dry matter accumulation and nitrogen accumulation, and significantly improve water and nitrogen use efficiency.
【学位授予单位】：中国农业大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：S513

【参考文献】