【作者】 李旭毅；

【导师】 马均；

【作者基本信息】 四川农业大学 ， 作物栽培学与耕作学， 2011， 博士

【摘要】 生态条件、氮肥调控措施和栽培方式均是影响水稻生产的重要因素,研究不同生态条件下各栽培方式适宜的氮肥调控原则和高产机制,对实现肥料的高效利用及水稻高产、稳产具有重要意义。本研究于2009-2010年在大田试验条件下,以代表性水稻品种杂交籼稻Ⅱ优498为材料,研究了温江和汉源两地不同施氮量和氮肥运筹方式下宽窄行栽培、三角形栽培、宽行窄株栽培、抛秧栽培对水稻库源构建、光合生产及产量形成的影响。主要研究结果如下：1、两种生态条件下氮肥调控和栽培方式对水稻群体质量及产量形成的影响温光条件优越的汉源点水稻群体质量指标得到改善,抽穗前后物质积累量显著增加,产量性状全面提高是其产量潜力显著增大的原因；高产群体的产量形成方面,温江点表现为穗稳(满足一定穗数)、粒足(每穗颖花数多)、结实率高,而汉源点则表现为足穗大穗。施氮量过高或过低均不利于在较高LAI水平上实现群体质量的提高；穗肥施用比例的增加虽然降低了LAI,但有利于改善抽穗后群体质量。结合群体质量、物质生产及产量结果看,各栽培方式在两地最佳施氮量均为180 kg hm2，此施氮量下宽窄行和三角形栽培氮肥运筹措施以基肥：蘖肥：穗肥比例为6：3：1最佳,宽行窄株栽培方式以5：2：3的氮肥运筹比例最佳,抛秧栽培温江点和汉源点最佳氮肥运筹比例分别为4：1：5和5：2：3。因此,在不同生态条件针对栽培方式采取适宜的氮肥调控措施是在合理群体基础上实现改善群体质量,增加抽穗后物质生产能力,从而提高产量的根本途径。本研究也提出了不同生态条件下的杂交稻高产群体质量指标,且发现不同栽培方式群体构建差异较大,达到高产群体指标的难易不一,但在温江点均能通过适宜的氮肥调控措施实现在较高水平下群体质量的改善,然而在温光条件更为优越的汉源点宽窄行、宽行窄株及抛秧栽培构建超高产群体的难度增大,增产潜力不及三角形栽培。2、两种生态条件下氮肥调控和栽培方式对水稻库源构建的影响在汉源点库源特征表现为库大源强,穗颈维管束性状虽得到提高,但源端输出同化物的增加导致流负荷有所增大,库端同化物的供应仍相对不足,灌浆强度难以提高,然而灌浆活跃时间的延长使籽粒接受的灌浆物质更为充足,籽粒充实率和充实指数升高,最终库容有效充实率和实际充实量均显著增加。此外,温江点产量的提高在于一定库容下籽粒充实水平的提高,且该生态条件下籽粒灌浆充实水平的下降和流负荷的增大有关；而汉源点产量的提高则在于库容扩大的同时籽粒充实水平有所提高,库容扩大后流的限制对籽粒灌浆充实的影响较小,因此加强源的供应能力成为提高籽粒灌浆充实水平的关键。适宜施氮量可以促进水稻群体叶源、茎鞘源和根源的协调发展,源能力加强,库容得到扩大,维管束的转运效率增强,灌浆充实良好,在较高水平下实现库源流的协调发展,从而库容实际充实量得到提高。随穗肥施用比例的提高,源能力加强的同时群体库容虽有所减少,促进了籽粒灌浆充实,最终增加库容有效充实度以提高库实际充实量。然而在汉源点,过多增加穗肥施用比例难以进一步提高籽粒充实程度,库容量和库有效充实度同时降低,库容实际充实量下降。不同生态条件下各栽培方式高产库源特征所采用的氮肥调控措施并不一致,表现为：在适宜的施氮量和较高的基蘖肥施用比例下,宽窄行和三角形栽培群体源能力加强,流经穗颈的同化物虽然增多但流负荷并无显著增加,促进了籽粒灌浆充实,最终库容实际充实量提高,然而在温光条件更为优越的汉源点该施氮量下三角形栽培更有利于实现更高水平下的源、库、流协调,库容实际充实量最大。对宽行窄株和抛秧栽培而言,基蘖肥施用比例的减少是改善其抽穗后“源”质量,增强源生产能力,协调库源关系,促进籽粒灌浆充实,进而提高库容实际充实量的重要措施。3、两种生态条件下氮肥调控和栽培方式对光合生产的影响汉源点水稻冠层结构更为合理,单叶和群体光合性能改善,各生育阶段群体生长率(CGR)增加,光合生产能力(尤其是抽穗后)显著高于温江点。氮肥施用量的增加扩大了上三叶光合面积,提高了剑叶净光合速率(Pn),生育前期CGR因叶积(LAD)的增加而提高,但剑叶Pn位差的增大不利于提高下部叶片光合性能,抽穗后CGR受净同化率(NAR)影响表现为显著降低,因而施氮量过低过高均不利于抽穗后光合生产能力的提高。随穗肥施用比例的提高冠层内的透光条件得到改善,植株叶片光合性能得以提高,群体呼吸消耗所占比例(CR/TCAP)减少,抽穗后CGR受NAR主导呈上升趋势,但过多的增加穗肥施用比例导致群体光合速率(CAP)难以提高。氮肥调控措施对各栽培方式光合生产的影响并不一致,表现为三角形栽培和宽窄行栽培改变植株的田间分布,在基蘖肥比例较高的条件下上三叶大小、叶片厚度及冠层透光性能提高,抽穗后植株叶片和群体光合性能均得到提高,抽穗后LAD和NAR的同步增加促进了CGR的提高,抽穗后光合生产优势明显,当温光条件改善后三角形栽培光合生产的优势得到加强,而宽窄行栽培光合生产优势并无体现。在适宜的氮肥运筹比例下,宽行窄株栽培和抛秧栽培抽穗后冠层特性相关指标等方面的差异减小,叶片同化能力和碳代谢增强,群体光合生产能力得以提高,LAD、NAR的同步上升促进了CGR的升高,抽穗前后光合生产得到协调发展。4、两种生态条件下氮肥调控和栽培方式对太阳辐射利用率(RUE)的影响不同生态条件下,RUE和产量存在极显著的正相关关系。在温江点结实中前期RUE和产量关系密切,增加高效和有效叶面积率及比叶重以改善群体质量是提高整个结实期RUE水平的关键,而在汉源点拔节至抽穗后15d这一阶段RUE的提高是发掘水稻产量潜力的关键,且RUE的增加更强调群体数量基础上质量的提高。试验结果还表明,在较高的穗肥比例下窄行和三角形栽培有利于提高抽穗后RUE,进而提高整个大田生长期的RUE,但温光条件改善后宽窄行栽培RUE高的优势减弱,三角形栽培却得到加强；宽行窄株栽培和抛秧栽培关键时期RUE乃至整个大田生长期RUE的提高则有赖于穗肥施用比例的提高。因此,各栽培方式应根据生态条件采用适宜的氮肥调控措施,实现提高RUE,进而发掘产量潜力的目的。更多还原

【Abstract】 Ecological condition, nitrogen regulation and cultivation model are important factors affect rice production, the study on optimization nitrogen regulation principle and high-yielding mechanism for kinds of cultivation models at different ecological condition would have a great significance in fertilizer efficient utilization and high and stable yields for rice. The effects of nitrogen regulation and cultivation models on sink-source construction, photosynthetic production and yield formation were studied under field at Wenjiang and Hanyuan by hybrid rice Eryou 498 during 2009 to 2010. the nitrogen regulation measure included nitrogen application rate and nitrogen application stagey, and cultivation models included wide-narrow row spacing cultivation, triangle cultivation, planting with the wide row and narrow plant space, scattered planting cultivation. The main results are follows:1. Effects of nitrogen regulation and cultivation modes on population and yield formation in rice at two ecological conditionsBecause of improving population quality, increasing dry matter accumulation and comprehensively improving yield components at Hanyuan with a superior temperature and light condition, the yield potential improved significantly; The high yield population had suitable productive panicles number, more spikelet number per panicle and higher seed setting rate at Wenjiang, while had sufficient productive panicles number and large panicle at Hanyuan. It is no avail to improving population quality basing on high LAI (leaf area index) under too high or too low nitrogen application rate. With increasing ratio of nitrogen application at panicle initiation stage, the LAI decreased, but population quality after heading improved.From the above, the 180 kg ha-1 of nitrogen application is the optimum amount for all cultivation models. when the total nitrogen application amount was 180 kg ha-1, the rational ratio of nitrogen application for transplanting stage, tillering stage and booting stage was 6:3:1 under wide-narrow row spacing cultivation and triangle cultivation, 5:2:3 under planting with the wide row and narrow plant space,4:1:5 and 5:2:3 under scattered planting cultivation at Wenjiang and Hanyuan respectively. It was suggested that achieving high yield by improving crop population quality basing on reasonable population size and increasing dry matter production after heading should adopt suitable nitrogen application strategy according to ecological condition and cultivation model. The study also proposed population quality indexes of super-high yielding-rice at two kinds of ecological conditions, and found there were different ways to construct population under different cultivation models, so the difficulty of each cultivation models in meeting requirement of high yield population was various. All kinds of cultivation models could improving population quality basing higher levels under suitable nitrogen regulation, but it is difficult to construct high yield population for wide-narrow row spacing cultivation and planting with the wide row and narrow plant space as well as scattered planting cultivation at Hanyuan with a superior temperature and light condition, their yield potential was lower than triangle cultivation.2. Effects of nitrogen regulation and cultivation modes on sink-source construction in rice at two ecological conditionsThe sink-source characteristics at Hanyuan showed that sink potential enlarged and source enhanced. Though the characters of the vascular bundles of the neck-panicle improved, the flow loading not decreased for more assimilates exported from source, and assimilates supplying rate for sink was insufficient, so it was difficult to increase filling intensity. However, because filling substance received by grain was more abundant by prolonging active filling time, grain filling rate and grain plumpness index increased, and accordingly effective sink-filling rate and actual sink-filling amount improved significantly.Besides, improve grain filling level basing enough size of sink was critical to increasing grain yield at Wenjiang, and overburden flow loading resulted in poor grain filling; Obtaining a high yield at Hanyuan depended on simultaneous enlarging sink size and improving grain filling to some extent, because the effects of flow limitation caused by enlarging sink size on grain filling decreased, the supply capacity of source was the key to achieve high level of grain filling. Under suitable nitrogen application rate, the capacity of source improved by coordinative development in leaf and stem as well as root, sink potential enlarged, transfer efficiency of the vascular bundles increased, so grain filling showed good, sink and source as well as flow got a coordinate development at a high level, actual sink-filling amount improved finally. With increasing ratio of nitrogen application at panicle initiation stage, the capacity of source improved although sink potential decreased, it is beneficial to promote grain filling. As a result, actual sink-filling amount improved by increasing effective sink-filling rate at Wenjiang. but at Hanyuan, it was difficult to improve grain filling by excessive increasing ratio of nitrogen application at panicle initiation stage, which would led to decreasing actual sink-filling amount for cutting down sink potential. In order to establish high yield population at different ecological condition, the suitable nitrogen regulation measures should be adopted according to different cultivation model. Under suitable nitrogen application rate or higher ratio of nitrogen application at basic and tillering, for wide-narrow row spacing cultivation and triangle cultivation, the source-capacity improved, assimilates through neck-panicle increased while flow loading not increased significantly, the grain filling was better, so their actual sink-filling amount improved. Because of getting a coordinate development in sink and source as well as flow under triangle cultivation, its actual sink-filling amount was higher than others. For planting with the wide row and narrow plant space and scattered planting cultivation, it was critical to limiting development of population at early-middle stage, increasing source production ability by improving source quality after heading, coordinating sink-source relationship, promoting grain filling, and improving actual sink-filling finally by decreasing ratio of nitrogen application at basic and tillering.3. Effects of nitrogen regulation and cultivation modes on photosynthetic production in rice at two ecological conditionsThough establishing more reasonable canopy morphological structure, improving single leaf and population photosynthetic characteristics and increasing crop growth rate (CGR), photosynthetic production at Hanyuan was higher than at Wenjiang(especially after heading).With increasing nitrogen application rate, photosynthetic area from flag leaf to third leaf of productive tillers expanded, photosynthetic rate(Pn) in flag leaf was increased, CGR increased with leaf area duration increased during early stage, but photosynthetic characteristics of lower leaf degradation because of rising in photosynthetic disparity in leaf position for Photosynthetic rate in flag leaf, CGR impacted by net assimilation rate(NAR) decreased significantly after heading, so too low or too high nitrogen application rate was not favorable for improving capacity of photosynthetic production. By increasing ratio of nitrogen application at panicle initiation stage, the canopy light transmittance performance improved, leaf photosynthetic characteristics increased, ratio of canopy respiration to total canopy apparent photosynthesis (CR/TCAP) tended to decrease, CGR impacted by NAR showed an increasing tendency, and it was difficult to promote canopy apparent photosynthesis (CAP) under excess nitrogen application rate. The effects of nitrogen regulation on photosynthetic production for cultivation models were not in agreement, it showed that:wide-narrow row spacing cultivation and triangle cultivation change distribution form of plants on field, when the ratio of nitrogen application was 6:3:1, their area from flag leaf to third leaf of productive tillers and Leaf specific weight as well as canopy light transmittance performance all improved, leaf and population photosynthetic characteristics tended increase, CGR was raised for both LAD and NAR increasing, so they had a great advantage in photosynthetic production after heading. However, once temperature and light conditions was improved at Hanyuan, the advantage of triangle cultivation enhanced, while wide-narrow row spacing cultivation reduced. For sprase planting by expanding spacing and reducing plant space and scattered planting cultivation, the difference between them with other cultivation models on canopy characteristics after heading reduced, increase amplitude in leaf assimilation capacity and index related carbon metabolism was higher, capability of photosynthetic production improved, CGR promoted by increasing of both LAD and NAR, so their photosynthetic production Pre-and post heading get a harmonious development under suitable nitrogen application stagey.4. Effects of nitrogen regulation and cultivation modes on radiation use efficiency (RUE) at different ecological conditionCorrelation analysis indicated that there existed very significantly positive correlations between RUE with grain yield at different ecological conditions. There was a close relationship between RUE during early-middle period of filling stage with grain yield at Wenjiang, improving crop population by increasing leaf area from flag leaf to third leaf of productive tillers, leaf area of productive tillers and leaf specific weight was the key to improve RUE during filling stage. But at Hanyuan, improving RUE from jointing to 15 days after heading was the key of yield increase, and the better crop population basing on enough population quantity played a critical role in improvement of RUE. When ratio of basic and tillering nitrogen applied was high, it is beneficial to improve RUE after heading for wide-narrow row spacing cultivation and triangle cultivation, thus their RUE improved during the whole lifetime. Once temperature and light conditions have improved, the advantage in RUE under wide-narrow row spacing cultivation decreased, while the advantage under triangle cultivation increased. The improvement of RUE under planting with the wide row and narrow plant space or scattered planting cultivation during critical stage and even whole lifetime depended on increasing ratio of nitrogen application at panicle initiation stage. In order to reach high yield by improving RUE, each cultivation model should adopted respective suitable nitrogen regulation according to ecological condition.更多还原