【作者】 赵光明；

【导师】 张福锁； 马德全； 苗宇新；

【作者基本信息】 中国农业大学 ， 植物营养学， 2014， 博士

【摘要】 为满足人口增长对水稻产量提高的需求,协调水肥资源过度消耗,资源利用效率低的矛盾,同时实现高产和资源的高效是当前水稻生产的重要目标。本文以黑龙江农垦寒地水稻典型代表区域七星农场为例,研究该地区水稻高产高效的限制因素,并在此基础上探索实现水稻高产高效的技术途径。首先,本文通过对当地农户生产现状的广泛调查研究,了解当前的水稻产量、养分效率的提高潜力,明确限制当前水稻生产增产增效的主要因素。在此基础上,利用课题组10个水稻试验的大样本数据,分析了寒地水稻的生长发育、产量构成对最终产量形成的影响,重点研究了高产水稻不同生育阶段的生物量累积和氮素吸收规律。根据以上结果,结合文献资料,集成了针对三江地区寒地水稻的包括优化栽培密度、水分和养分管理的高产高效综合管理技术体系(IRM),并进行了田间小区试验验证。最后,本文又将IRM进行了不同尺度农户田块的示范与推广,探索IRM的示范推广应用效果、前景及存在的问题。取得的主要结果如下：(1)通过大量农户生产现状的调查数据,借鉴本课题组Oryza2000水稻模型的模拟结果、结合高产典型资料收集,研究发现本地区寒地水稻仍有30-54%的产量和19%的效率提高潜力,并找到产量和效率提高的限制因素。限制当前产量和效率提高的主要因素有：(a)对品种特性了解不够、栽培密度偏稀,60%以上的农户栽插密度每平方米不足27穴；(b)氮肥施用盲目、前期施用比例过大,将近90%的氮肥用在了前期,并有将近一半的农户后期不追氮；(c)50%的农户磷肥施用过量、40%的农户钾肥施用不足；(d)水分管理上,仍有相当一部分的农户认为水稻需要持续的有水层灌溉。(2)通过对10个水稻试验综合分析研究,发现寒地水稻产量的提高更多依赖于单位面积穗数和生物量的增加,穗粒数和收获系数对其影响较小,与结实率和千粒重关系不显著；穗分化至抽穗期是生物量累积和氮素吸收最快、最多的时期,穗分化-抽穗、花后氮素吸收量和花后生物量的高量累积及比例是高产和中低产产量差异的主要原因。(3)根据以上研究结果,结合水肥优化管理文献资料查阅,集成了IRM,并进行了田间小区试验验证。与农户常规管理体系相比,仅优化水肥的高效管理技术体系在保证相同产量水平的基础上,氮肥回收利用率(RE)、农学利用率(AE)和偏生产力(PFP)分别提高63%、46%和49%；IRM在RE、AE、PFP分别提高97%、95%和51%的同时,产量提高10%。另外,与FP相比,IRM能够改善群体质量,显著降低倒伏风险。与高投入的高产管理体系(HYM)相比,IRM在保证产量相同的情况下,节省氮肥21%,AE和PFP分别提高22%和27%。(4)本文又将IRM进行了农户田块不同尺度的示范与推广,结果表明,高产高效示范管理平均产量、PFP和AE较农户常规管理相对提高了9%、10%和26%,有一定的示范推广前景。但示范产量和氮肥利用率提高程度的差异比较大,从高到低依次为示范田块、辐射田块和大面积推广田块,技术上的简化、污染和技术本身的一些局限性是造成这种差异的主要原因。更多还原

【Abstract】 To feed the increasing population and improve the resources use efficiency (RUE), the goal of rice (Oryza sativa L.) production is to achieve high grain yield and high RUE simultaneously. This study has focused on the rice production in cold region in Heilongjiang Province, with Qixing Farm as a case study, to identify the limited factors to improve yield and then develop an integrated rice management system (IRM). Initially, through intensive farm surveys, the potential and constrains for further increasing grain yield and RUE were investigated. Using results of ten field experiments, this study analyzed the influence of rice development and yield components on final yield, and the dynamics of dry matter and nitrogen (N) accumulation. Based on the above analyses, together with the reported results for current optimized rice management in literatures, we have developed the IRM, which included the optimization of density, nutrient and water management. Meanwhile, IRM was validated by field trials to evaluate the agronomic performance on population quality, yield and RUE. Finally, the IRM was further applied to different sizes of farms to further explore the effect, prospects and problems of IRM application over large areas. The main results were as follows:(1) Through farm surveys, simulations with Oryza2000model in our group, together with the recorded yield, we found local rice still has the potential to increase yield by30-54%and RUE by19%. The factors to constrain grain yield improvement included (a) Limited understanding of variety characteristics;(b) Lower planting density with more than60%of farmers below27hills m"2;(c) Improper timing of N application, with nearly90%of N fertilizer being applied at the early growth stage and half farmers not applying topdressing N fertilizers;(d) Unsuitable P and K fertilization, with50%of farmers overused phosphate fertilizer and40%of farmers failed to applied enough potassium fertilizer;(e) Improper water management, with many farmers still believing that rice need continuous flooding for whole growing season.(2) Through ten field experiments, we found yield improvement relied on panicle number per unit area and dry matter accumulation, and was less affected by grains per panicle and harvest index. Yield was not significantly affected by spikelet fertility and thousand grain weight. Panicle initiation to heading stage was the most important and fastest stage for dry matter and N accumulation. N and dry matter accumulation from panicle initiation to heading and post-anthesis had the most important influence on grain yield.(3) Based on the above analysis, together with the reported results for current optimized management in literatures, we have developed the IRM and verified it in fields. Compared with farmers’ practice, the N recovery use efficiency (RE), N agronomic use efficiency (AE), and N partial factor productivity (PFP) were improved by63%,46%, and49%, respectively, if only water and N management were optimized while grain yield was maintained. Compared with fanners’ practice, the IRM improved the RE, AE and PFP by97%,95%, and51%, respectively, while grain yield was increases by10%. Meanwhile, the IRM increased the population quality and reduced the risk of lodging in large extent. Compared with the high yield system,21%of N fertilizer was reduced in IRM while high grain yield was maintained. Meanwhile, AE and PFP were improved by22%and27%, respectively in IRM.(4) The IRM has been further applied to different sizes of farms as demonstrations. The results showed IRM could increase grain yield, PFP and AE by9%,10%and26%, respectively. However, the percent of improvements in yield and NUE was reduced from small demonstration fields, technology influenced fields to large extension fields. These differences were caused by simplification of management, technology contamination and technology limitations, etc.更多还原