【作者】 王宜伦；

【导师】 李潮海；

【作者基本信息】 河南农业大学 ， 作物栽培学与耕作学， 2010， 博士

【摘要】 超高产栽培是提高玉米总产量、保障国家粮食安全的重要战略途径,目前超高产夏玉米生产普遍存在施肥过量（尤其是氮肥）、养分配比不平衡、施肥时期不合理等现象,明确超高产夏玉米养分限制因素,氮磷钾肥增产效应及合理的配比,氮素吸收积累特性、适宜的氮肥用量和施氮时期等,对实现夏玉米高产、高效和简化生产具有重要的理论意义和实践价值。然而,超高产夏玉米需肥规律及合理的施肥技术鲜见报道,本文从2007²009年,在河南省浚县夏玉米高产区,通过田间试验（氮磷钾肥平衡施肥效应、氮肥用量、施氮时期、不同品种氮肥效应以及缓控释肥一次性施肥等）,研究了超高产夏玉米养分限制因子及养分吸收积累特性,重点研究了超高产夏玉米氮素吸收积累特性、氮肥经济最佳用量及其效应、氮肥后移增产效果及其生理基础、施氮量对不同超高产夏玉米品种产量及氮素吸收利用的影响、缓/控释氮肥一次性施肥技术及其效果等,以期为超高产夏玉米合理施肥提供理论依据和技术支撑。通过研究获得如下结论。1、超高产夏玉米养分限制因子和植株养分吸收积累特性研究表明,用ASI法推荐的氮磷钾平衡施肥产量最高,分别达到12051.2 kg·hm^-2和13246.3 kg·hm^-2,施用氮肥平均增产8.92%,钾肥平均增产7.14%,增产效果显著,氮和钾为超高产夏玉米养分主要限制因子。超高产夏玉米植株体内氮、磷、钾的积累量均随生育期的延长而增加,到成熟期达到最大值,养分积累量的大小顺序为氮>钾>磷,每生产100 kg经济产量吸收N:P2O5:K2O比例为2.40:1:2.73。拔节期至吐丝期是养分吸收的关键时期,养分吸收速率大,积累量高,吐丝后植株仍能吸收较多的氮和磷。从出苗到吐丝,叶片是氮、磷的分配中心,生育后期茎叶中氮、磷的转运率较高,而钾转移比例较小。超高产夏玉米整个生育期能持续吸收养分,吐丝后适当追肥保证灌浆期养分充足供应对夏玉米超高产至关重要。氮磷钾平衡施肥有利于夏玉米籽粒品质的改善,提高了夏玉米蛋白质产量。2、超高产夏玉米经济最佳氮肥用量及其效应研究结果表明,随着氮肥用量增加,夏玉米产量呈先增加后降低趋势,以施氮量300 kg·hm^-2产量和收益最佳,分别为11753.64 kg·hm^-2和13246.32 kg·hm^-2、2063.33元·hm^-2和2364.84元·hm^-2,经济最佳施氮量为255.4 kg·hm^-2,超过450 kg·hm^-2夏玉米施氮已无经济效益。适宜的施氮量有利于提高硝酸还原酶、蔗糖磷酸合成酶和谷氨酰胺合成酶的活性,促进氮代谢的适宜氮肥用量为300 kg·hm^-2,有利于氮素的吸收积累。夏玉米氮肥利用效率随着氮肥用量增加而降低,施氮量300 kg·hm^-2的氮肥利用率、农学效率和偏生产力两年平均值分别为16.12%、3.69 kg·kg^-1和41.67 kg·kg^-1。从产量、经济收益、氮代谢、氮素积累和氮肥利用效率等方面综合考虑,超高产夏玉米合理的氮肥用量为255～300 kg·hm^-2。3、超高产夏玉米氮肥运筹研究表明,超高产夏玉米吐丝后氮素吸收积累量占总积累量的40.30%⁴7.78%,保证后期氮素养分充足供应对于夏玉米达到超高产水平至关重要;氮肥后移可维持夏玉米生育后期较高的叶面积指数和叶绿素含量,促进超高产夏玉米后期的氮素吸收积累,降低夏玉米茎和叶片氮素的转运率,显著增强灌浆期夏玉米穗位叶硝酸还原酶活性、蔗糖磷酸合成酶和谷氨酰胺合成酶活性,提高灌浆期叶片游离氨基酸和可溶性糖含量,增加蛋白质产量;氮肥后移比习惯施氮增产2.27%⁵.33%、氮肥利用率提高1.88%⁹.70%、农学效率提高0.96².21 kg·kg^-1,以“30%苗肥+30%大喇叭口肥+40%吐丝肥”方式施用氮肥的产量和氮肥利用效率最佳。4、超高产夏玉米缓/控释氮肥一次性施肥效果研究结果表明,苗期一次性施用缓/控释氮肥的植株氮素积累量比常规2次施氮提高了6%⁷%,产量提高了3%⁴%,氮肥利用率提高5%,氮肥农学效率提高了1.26¹.59 kg·kg^-1;施用缓/控释氮肥有利于超高产夏玉米生育后期氮素吸收利用,维持了灌浆期叶片较高的叶绿素含量,有利于籽粒灌浆,显著提高了夏玉米籽粒油分、粗蛋白、粗脂肪含量,同时提高了夏玉米产量和氮肥利用效率。采用夏玉米专用缓/控释肥一次性施肥简化了施肥程序,实现了超高产夏玉米简化、高产、优质和高效施肥。5、施氮对两个超高产夏玉米品种的效应研究表明,郑单958在低氮时产量和收益最高,分别为12051.18 kg·hm^-2和1722.40元·hm^-2,而浚单20在高氮时产量和收益最佳,分别为13166.00 kg·hm^-2和1343.92元·hm^-2,在0、240和450 kg·hm^-2三个氮水平下比郑单958分别增产9.90%、5.20%和12.00%;浚单20在大喇叭口-吐丝期的氮素吸收积累和吸收速率高于郑单958,灌浆后期高氮水平的氮素吸收速率亦远大于郑单958;高氮水平下浚单20的氮素利用效率、氮肥利用率和氮肥偏生产力显著高于郑单958,高施氮量有利于浚单20获得较高的蛋白质产量。从产量、氮素吸收、氮素效率及蛋白质产量综合考虑,浚单20是氮肥高效品种。6、氮肥运筹对晚收夏玉米的效应研究表明:氮肥后移和缓/控释氮肥使夏玉米在晚收条件下较习惯施氮增产7.23%⁹.52%,蛋白质产量增加6.26%¹0.73%,晚收较习惯收获产量增加2.12%⁶.42%、蛋白质产量增加1.11%～7.68%、氮积累量增加1.10%³.18%;晚收夏玉米茎和籽粒氮积累量增加,而叶和其它器官中积累量减少;氮肥后移和缓/控释氮肥在晚收条件下氮肥利用率提高了3.52%⁶.87%,氮肥农学效率提高了0.82¹.60 kg·kg^-1。更多还原

【Abstract】 The production of super-high-yield summer maize is an important strategic way to improve the production of maize and ensure the national food security. At present phenomenons such as excessive fertilizer（especially nitrogen）、unbalanced nutrient ratio、unreasonable fertilizer application times and so on were widespread. Therefore it has the important theoretical and practical value to clear the limiting nutrient factors、yield responses to applied NPK and balanced nutrient ratio、the characters of assimilation and accumulation of nitrogen、appropriate nitrogen application and reasonable fertilizer application times and so on, then to realize the aim of high yield , high efficiency fertilization, simplify of super-high-yield summer maize. However, the reports about the nutrition requirement of crops and appropriate fertilization techniques of super-high-yield summer maize are rarely to seen. Therefore, in the area of high yield of summer maize of xunxian, Henan Province, according to different soils, we recommended balanced fertilization from 2007 to 2009. We also made research on the limiting nutrient factors and the characters of nutrient assimilation and accumulation of super-high-yield summer maize systematically; This paper focused on the characters of nitrogen assimilation and accumulation、economic optimum nitrogen fertilizer and its effect、the effect of postponing N application on increasing yield and its physiological bases、the effect of nitrogen fertilizer on yield and nitrogen absorption and utilization of different kinds of super-high-yield summer maize、the techniques of single application of base fertilizer （slow/controlled release N fertilizer） and its effect, which to provide theoretical basis and technological support for proper fertilizer management of super-high-yield summer maize.1. The research of soil nutrient restrictive factors and plant nutrient uptake and accumulation of super-high-yield summer maize showed that the maize yields are highest under the OPT treatment （By ASI）, 12051.2 kg·hm^-2 and 13246.3 kg·hm^-2 in 2007 and 2008 respectively. The nitrogen and potassium fertilization could evidently increase the yields by 8.92% and 7.14%, which indicates N and K are main nutrient restrictive factors. The accumulations of nitrogen, phosphorus and potassium of super-high-yield summer maize plants are increased with the extension of the bearing period, and the nutrient accumulation amounts are maximum at the maturity stage. The order of nutrient accumulations is K2O>N>P2O5, and the absorbed nutrient ratio with 100 kilogram maize of N, P2O5 and K2O are 2.40:1:2.73. The key period of nutrient absorption is from the jointing stage to silking stage, and the absorbed nutrient rates are the highest. After the silking stage, maize plant absorbs more nitrogen and phosphorus. Leaf is distribution center of nitrogen and phosphorus from the seeding stage to silking stage, and the transfer efficiency of nitrogen and phosphorus are higher in stems and leaves at the late stages, while the transfer proportion of potassium is small. Nutrients are absorbed continuously at the whole growth period of super-high-yield summer maize, it is essential to super-high-yield topdressing after the silking stage that ensure adequate nutrients at the grain filling stage. Balanced NPK fertilization can improve quality of maize grain, increase production of maize protein, chlorophyll content, leaf area index and harvest index.2. The results of economic optimum nitrogen fertilizer of super-high-yield summer maize and its effect showed that with the increased nitrogen levels, the production of summer maize was fist increased then decreased, under 300 kg·hm^-2 nitrogen application, the yield and incomes were the best, 11753.64 kg·hm^-2 and 13246.32kg·hm^-2、2063.33yuan·hm^-2 and 2364.84 yuan·hm^-2 respectively, the economic optimum nitrogen application is 255.4 kg·hm^-2, there were no economic benefits for summer maize when exceeded nitrogen application of 450 kg·hm^-2. Proper nitrogen application could increase the activity of nitrate reductase、sucrose phosphate synthase and glutamine synthetase. The proper nitrogen application to promote nitrogen metabolism is 300 kg·hm^-2, it also could promote the assimilation and accumulation of nitrogen. With the increase of nitrogen application, the nitrogen use efficiency of summer maize was decreased, with the nitrogen application of 300 kg·hm^-2, the means of two years’data of nitrogen use efficiency、agronomic efficiency and partial factor productivity were 16.12%、3.69 kg·kg^-1 and 41.67 kg·kg^-1 respectively. Considering the yield、economic benefits、nitrogen metabolism、accumulation of nitrogen、nitrogen use efficiency and so on, the proper nitrogen application were 255-300 kg·hm^-2 of super-high-yield summer maize.3. The research on effect of postponing N application on yield, nitrogen absorption and utilization in super-high-yield summer maize and its physiological bases showed that compared with conventional fertilizer application, postponing N application increased grain yield by 2.27%–5.33%. The N absorption proportion after silking stage was 40.30%–47.78% of the total, so it is important to provide maize plants with sufficient N in later growth stage for realizing super-high-yield. At later stage postponing N application could keep high leaf area index and chlorophyll content, promote N absorption and accumulation of super-high-yield summer maize at later stage, decrease N transfer efficiency in stem and leaf, increase activity of nitrate reductase、sucrose phosphate synthase、glutamine synthetase and content of free amino acids and soluble sugar in ear leaf at filling stage, and raise protein yield of summer maize. In comparison with conventional fertilizer application, the N fertilizer utilization rate and N fertilizer agronomy efficiency were increased by 1.88%–9.70% and 0.96–2.21 kg·kg^-1 respectively by postponing N application. The highest yield and nitrogenous fertilizer use efficiency were obtained by applying 30% of nitrogen fertilizer at seedling stage and trumpeting stage respectively and 40% of nitrogen fertilizer at silking stage.4. The studies on single application of base fertilizer （slow/controlled release N fertilizer）of super-high-yield summer maize showed that the plant N accumulation , yield, N fertilizer utilization rate and N fertilizer agronomy efficiency of CRNF improved by 6-7%, 3-4%, 5%, and 1.26-1.59 kg·kg^-1 compared with the conventional fertilizer application respectively; CRNF increased N absorption and utilization in the late growing periods, kept high chlorophyll content in leaf at filling stage, promoted grain filling and increased the content of maize kernel oil, crude protein, crude fat, protein yield, yield and nitrogen use efficiency. Applying CRNF was beneficial to realize single appli0cation of base fertilizer and the aim of simplify, high yield and high efficiency fertilization of super-high-yield summer maize.5. The research on effect of nitrogen fertilizer on yield and nitrogen absorption and utilization of two kinds of super-high-yield summer maize showed that the yield and incomes of Zhengdan 958 were the highest under low nitrogen condition, 12051.18 kg·hm^-2 and 1722.40 yuan·hm^-2 respectively, but the yield and incomes of Xundan 20 were the best under high nitrogen condition, 13166.00 kg·hm^-2 and 1343.92 yuan·hm^-2 respectively, the yield at three levels(N 0, 240 and 450 kg·hm^-2 )of Xundan20 increased by 9.90%、5.20% and 12.00% respectively, compared with Zhengdan958; From trumpeting stage to silking stage, the amount of assimilation and accumulation of nitrogen and absorption rate of nitrogen of Xundan 20 were higher than those of Zhengdan 958. At high N level, the absorption rate of nitrogen of Xundan 20 was also much more than that of Zhengdan958 at the later filling stage; The N use efficiencies, N use rate and N partial factor productivity of Xundan20 at high N level were significantly higher than those of Zhengdan 958, higher N application was beneficial to Xundan20 to get more production of protein. Considering the yield、nitrogen absorption、nitrogen efficiency and production of protein, Xundan20 is a nitrogen-efficient maize compared with Zhengdan 958.6. The results of the effect of nitrogen management on yield, quality, nitrogen absorption and utilization of summer maize in later harvest time showed that compared with local farmer habitual usage of N, postponing N fertilizer application and slow/controlled release N fertilizer could increase grain yield by 7.23%-9.52% and production of protein by 6.26%-10.73% in later harvest time; Compared with accustomed harvest, later harvest’s yield increased by 2.12% - 6.42%, production of protein increased by 1.11%-7.68% and N accumulation increased by 1.10%-3.18%;The stem and grain N accumulation increased in later harvest time, while the leaves and other organs is reduced;Postponing N application and slow/controlled release N fertilizer increased N use efficiency by 3.52%-6.87% and N agronomic efficiency by 0.82-1.60 kg/kg in later harvest time.更多还原