【作者】 覃夏；

【导师】 王绍华； 薛利红；

【作者基本信息】 南京农业大学 ， 作物栽培学与耕作学， 2011， 硕士

【摘要】 本研究以常规籼稻为材料,在江西鹰潭双季稻区对早、晚稻设置不同密度、不同氮肥和不同密肥互作处理,研究双季稻群体生长、产量和氮素吸收与利用对密度、氮肥和密肥互作的响应,以不同年份、不同氮肥水平试验为基础,建立基于冠层NDVI的水稻LAI、植株干物质积累量和植株吸氮量的监测模型,并利用三年不同的独立试验数据对模型进行检验,主要研究结论如下：1、密度对早、晚稻群体生长和氮素吸收与利用的效应随着密度的减小,早、晚稻群体茎蘖数、LAI和干物质积累量都显著下降,早稻各个时期的植株吸氮量逐渐升高,而晚稻呈现先升高后降低的趋势,氮素利用效率都随着密度的增加先增后降；在低密度处理下,早、晚稻宽行窄株较等行株距茎蘖数、LAI和干物质积累量有所降低,而较高密度处理时宽行窄株较等行株距茎蘖数、LAI和干物质积累量增加,而在相同基本苗下,栽插穴数少、每穴栽插苗数多时早、晚稻各个时期茎蘖数、LAI和植株干重都显著下降,在株行距为10.0 cm×26.7 cm时,早稻和晚稻都获得较高产量2、氮肥对早、晚稻群体生长和氮素吸收与利用的效应氮肥用量的增加使群体茎蘖数、LAI和干物质积累量都呈增加的趋势,对植株吸氮量影响显著,在低氮水平,早稻植株吸氮量和氮素利用效率随基肥比例的增加而降低,氮水平较高时,则随着基肥比例的增加呈先增后降的趋势,晚稻植株吸氮量随着氮肥用量增加而增加,氮素转运率、氮素生理效率、氮素农学效率、氮素回收效率和氮肥偏生产力则表现为下降的趋势,随着基蘖肥用量的增加,晚稻氮素回收效率和氮肥偏生产力显著下降,而对氮素转运率和氮素生理效率影响不大；早稻氮肥-产量报酬曲线为明显的抛物线,最高产量出现在氮肥用量为180 kg/hm2和基肥：蘖肥：穗肥=33：42：25时,晚稻在较低氮肥用量就能获得较高产量,适宜的氮肥用量为180 kg/hm2且基蘖肥：穗肥=6：4。3、氮肥和密度对早、晚稻群体生长和氮素吸收与利用的效应不同的密度最适宜的氮肥用量不同,水稻前期在同一密度处理下,随着氮肥用量的增加茎蘖数、LAI、干物质积累量都有所增加,而拔节期以后随着氮肥用量的增加呈先增加后减少的趋势,早稻在同一密度处理下随着氮肥用量的增加吸氮量增加,晚稻则在低密度处理时吸氮量随氮肥用量增加而增加,在较高密度时则呈先增后减的趋势；早稻和晚稻最高产量都出现在株行距为13.3 cm×30.0 cm的密度处理下,此时早稻的氮肥用量为195 kg/hm2,晚稻为165 kg/hm2。4、基于冠层NDVI的双季稻群体长势监测和氮素诊断模型以4个氮肥试验数据为基础,分析了冠层NDVI与水稻LAI、植株干物质积累量和植株吸氮量的关系。结果表明,早稻分蘖期冠层NDVI与LAI、干物质积累量和吸氮量呈极显著的线性正相关,拔节期和齐穗期则呈现极显著的指数相关；晚稻分蘖期冠层NDVI与LAI呈极显著的线性正相关,拔节期和齐穗期冠层NDVI与LAI则呈现极显著的指数相关,而分蘖期、拔节期和齐穗期冠层NDVI与干物质积累量和吸氮量间均呈显著的指数相关。基于冠层NDVI与LAI、植株干物质积累量和植株吸氮量的关系,建立了18个监测模型,并利用6个独立试验数据对模型进行了检验,结果表明监测模型预测效果较好。更多还原

【Abstract】 These experiments was carried out to study the effects of different density, nitrogen fertilizer and their interaction on population growth, grain yield, nitrogen uptake and utilization of double-cropping rice (conventional varieties) at Yingtan City, Jiangxi Province. The monitoring model between canopy NDVI and LAI, dry matter accumulation, plant nitrogen uptake was developed using the data of experiment with different nitrogen and years, and the models were tested using independent experiment data of 3 years. The main conclusions were as followed:1. The effects of different density on population growth, nitrogen uptake and utilization of early and late riceWith the density decreasing, the population tiller number, LAI and dry matter accumulation at different growth stages of early and late rice decreased significantly, plant nitrogen uptake at different growth stages of early rice increased gradually, while late rice first increased then decreased, the nitrogen use efficiency of early and late rice both first increased then decreased. Under low density, the tiller number, LAI and dry matter accumulation of wide row and short space treatment lower than the same row and space treatment, and under the high density the trend is inversed. Under the same basic seedling, the tiller number, LAI and dry matter accumulation at different growth stages of early and late rice decreased significantly when more less transplanting pits and more planting seedling number per pits. The highest grain yield of early and late rice appeared at the planting spacing of 10.0 cm×26.7 cm treatments.2. The effects of different nitrogen fertilizer on population growth, nitrogen uptake and utilization of early and late ricePopulation tiller number, LAI and dry matter accumulation at different growth stages of early and late rice were increasing with nitrogen rate increasing. Under the low nitrogen levels, the increase of basal nitrogen ratio decreased the plant nitrogen uptake and nitrogen use efficiency of early rice, and first increased then decreased with the increasing of basal nitrogen ratio when nitrogen content was higher. With the nitrogen rate increasing, plant nitrogen uptake of late rice increased, nitrogen translocation efficiency (NTE), physiological efficiency (NPE), agronomic efficiency (NAE), recovery efficiency (NRE), and partial factor productivity of applied nitrogen (PEP) were decreasing, with basal fertilizer increased, recovery efficiency (NRE), and partial factor productivity of applied nitrogen (PEP) were decreased significantly, but the nitrogen translocation efficiency (NTE), physiological efficiency (NPE) have no significant difference.Nitrogen fertilizer were significantly curve correlated with the early rice grain yield, the treatment with the highest grain yield, were 180 kg/hm2 nitrogen level, and the ratio of basal, tiller and panicle was 33:42:25, and the optimum nitrogen rate of late rice was 180 kg/hm2, the ratio of basal and panicle nitrogen was 6:4.3. The effects of different nitrogen fertilizer and density on population growth, nitrogen uptake and utilization of early and late riceDifferent density has different optimum nitrogen fertilizer, in the early growth period of double-cropping rice, the increase of nitrogen rate increased the tiller number, LAI and dry matter accumulation while treated in the same density, but first increased then decreased after the jointing stages. In the same density, plant nitrogen uptake of early rice increased with the nitrogen increased, but late rice were increased in the low density treatment, first increasing then decreasing in higher density. At the planting spacing of 13.3 cm×30.0 cm treatments, the grain yield of early and late rice were the highest, and the nitrogen rate were 195 kg/hm2,165 kg/hm2 respectively.4. The models of growth condition monitoring and nitrogen nutrition diagnosis of double-cropping rice based on canopy NDVIAnalysis the relationship between canopy NDVI and LAI, plant dry matter accumulation and nitrogen uptake using the data of 3 years field experiment with different nitrogen treatments. The results shows that canopy NDVI was highly significant linear correlated with LAI, plant dry matter and nitrogen uptake of early rice at tillering stage, and was highly significant index correlated at jointing and full heading stages. At the tillering stage, the canopy NDVI was highly significant linear correlated with LAI, and was highly significant index correlated at jointing and full heading stages, and canopy NDVI was highly significant index correlated with plant dry matter accumulation and nitrogen uptake at different growth stages. And the author establishments 18 monitoring models tested those models using 6 independent experiment data, the tested results shows that those monitoring models forecasts better.更多还原