The erect panicle （Ep） type is an important characteristic for japonica super rice in Northeast China and plays a significant role in enhancing yield. The Ep type is considered to be a genetic ideotype resource to t...The erect panicle （Ep） type is an important characteristic for japonica super rice in Northeast China and plays a significant role in enhancing yield. The Ep type is considered to be a genetic ideotype resource to the japonica super rice group by virtue of its agronomic advantages such as grain number per panicle and biomass. This study addresses the effects of nitrogen and planting density conditions on yielding performance regarding panicle type （PT） using the recombinant inbred line （RIL） population derived from the cross between an Ep variety Liaogeng 5 and non-Ep variety Wanlun 422. The genetics underlying the Ep type proved to be robust not only for panicle-type optimization but also plant height, panicle length, flag leaf length and seed density. We also found that regardless of nitrogen and density, correlation between harvest index （HI） and plant height was not significant in Ep type whatever the nitrogen and density. The application of Ep type provides a potential strategy for yield improvement by increasing biomass through HI maintainable in rice.展开更多
In order to establish methods for indentification and screening of rice genotypes with high nitrogen （N） efficiency, N absorption efficiency （NAE）, N utilization efficiency （NUE） and N harvest index （NHI） in t...In order to establish methods for indentification and screening of rice genotypes with high nitrogen （N） efficiency, N absorption efficiency （NAE）, N utilization efficiency （NUE） and N harvest index （NHI） in ten rice genotypes were investgated at the elongation, booting, heading and maturity stages under six N levels in a pot experiment with soil-sand mixtures at various ratios. NAE in various rice genotypes firstly increased, peaked under a medium nitrogen rate of 0.177 g/kg and then decreased, but NUE and NHI always decreased with increasing nitrogen levels. NAE in various rice genotypes ever increased with growing process and NUE indicated a descending tendency of elongation stage〉heading stage〉maturity stage〉booting stage. N level influenced rice NAE, NUE and NHI most, followed by genotype, and the both effects were significant at 0.01 level. In addition, the interaction effects of genotype and nitrogen level on rice NAE and NUE were significant at 0.01 level, but not significant on rice NHI. Because the maximum differences of NAE and NUE were found at the elongation stage, it was thought to be the most suitable stage for identification and screening these two paremeters. Therefore, the optimum conditions for identification and screening of rice NAE, NUE and NHI in a pot experiment were the nitrogen rate of 0.157 g/kg at the elongation stage, low nitrogen at the elongation stage, and the nitrogen rate of 0.277 g/kg at the maturity stage, respectively.展开更多
A field study to evaluate the impact of different tillage regimes and nitrogen levels on yield and yield components of maize (Zea mays L.), was conducted during autumn 2014 at Students Farm, Department of Agronomy, Un...A field study to evaluate the impact of different tillage regimes and nitrogen levels on yield and yield components of maize (Zea mays L.), was conducted during autumn 2014 at Students Farm, Department of Agronomy, University of Agriculture, Faisalabad. The experiment was laid out in RCBD (Randomized Complete Block Design), with split plot arrangement having three replications. The experiment was comprised of three tillage regimes (Minimum, Conventional and Deep) and three nitrogen levels viz: 100, 200 and 300 kg•ha<sup>-1</sup>. Urea was used as a source of nitrogen, sulphate of potash as a source of potassium and triple super phosphate as a source of phosphorous. The amount of phosphorous and potash was constant in all the treatments i.e. 125 kg•ha<sup>-1</sup> and 100 kg•ha<sup>-1</sup> respectively. Results of present study are summarized as yield parameters are significantly affected by different nitrogen levels and tillage regimes. Maximum number of plants at harvest (7.93), number of grain rows per cob (17.70), number of grains per row (34.31), number of grains per cob (678.58), and cob weight (187.50 g) were observed in deep tillage at 200 kg•ha<sup>-1</sup> nitrogen application. 1000-grain weight (275.52 g), biological yield (15.66 t•ha<sup>-1</sup>), grain yield (6.16 t•ha<sup>-1</sup>) and dried stalk yield (9.91 t•ha<sup>-1</sup>) were observed maximum in deep tillage at 200 kg•ha<sup>-1</sup> nitrogen application. Harvest index significantly affected by tillage regimes and maximum harvest index (39.58%) were recorded in deep tillage which was statistically at par with conventional tillage (38.83%). It was concluded that higher grain yield of maize can be obtained by deep tillage with the application of 200 kg•ha<sup>-1</sup> nitrogen application under the prevailing conditions of Faisalabad.展开更多
为通过不同灌水施氮方式调控干旱区作物收获指数提高资源利用效率,以制种玉米"金西北22号"为供试材料,进行了为期2 a的田间试验。试验采用灌水方式(交替灌水、固定灌水、均匀灌水)与施氮方式(交替施氮、固定施氮、均匀施氮)...为通过不同灌水施氮方式调控干旱区作物收获指数提高资源利用效率,以制种玉米"金西北22号"为供试材料,进行了为期2 a的田间试验。试验采用灌水方式(交替灌水、固定灌水、均匀灌水)与施氮方式(交替施氮、固定施氮、均匀施氮)完全随机组合设计,测定生育期内作物耗水量(evapotranspiration,ET)和成熟期植株的生物量、籽粒产量及其构成(穗长、穗粗、行粒数和千粒质量等)和作物吸氮量,折算收获指数(harvest index,HI)、水分利用效率(water use efficiency,WUE)和氮利用效率(nitrogen use efficiency,NUE)。结果表明,灌水施氮方式只对行粒数有显著影响。ET只受灌水方式影响,交替灌水较其他灌水方式显著减小ET。WUE表现为:灌水方式相同时,交替施氮和均匀施氮大于固定施氮;施氮方式相同时,交替灌水>均匀灌水>固定灌水。玉米的吸氮量、HI和NUE与WUE表现出相似的规律。2013年交替灌水均匀施氮下制种玉米的HI、WUE和NUE最大,较均匀灌水均匀施氮分别增加5.46%、11.41%和19.73%。交替灌水交替施氮(水氮同区)的表现与交替灌水均匀施氮相似。2014年的结果与2013年一致。综上,交替隔沟灌溉均匀施氮和交替隔沟灌溉交替施氮(水氮同区)有利于提高制种玉米的产量和水氮利用效率。展开更多
基金supported by the National Key Research and Development Program of China(2016YFD0300504)the Cultivation Plan for Youth Agricultural Science and Technology Innovative Talents of Liaoning Province,China(2014046)
文摘The erect panicle （Ep） type is an important characteristic for japonica super rice in Northeast China and plays a significant role in enhancing yield. The Ep type is considered to be a genetic ideotype resource to the japonica super rice group by virtue of its agronomic advantages such as grain number per panicle and biomass. This study addresses the effects of nitrogen and planting density conditions on yielding performance regarding panicle type （PT） using the recombinant inbred line （RIL） population derived from the cross between an Ep variety Liaogeng 5 and non-Ep variety Wanlun 422. The genetics underlying the Ep type proved to be robust not only for panicle-type optimization but also plant height, panicle length, flag leaf length and seed density. We also found that regardless of nitrogen and density, correlation between harvest index （HI） and plant height was not significant in Ep type whatever the nitrogen and density. The application of Ep type provides a potential strategy for yield improvement by increasing biomass through HI maintainable in rice.
基金supported by the National High-Tech Research&Development program(Grant No.2003AA206030)the National Natural Science Foundation of China(Grant No.30030090)
文摘In order to establish methods for indentification and screening of rice genotypes with high nitrogen （N） efficiency, N absorption efficiency （NAE）, N utilization efficiency （NUE） and N harvest index （NHI） in ten rice genotypes were investgated at the elongation, booting, heading and maturity stages under six N levels in a pot experiment with soil-sand mixtures at various ratios. NAE in various rice genotypes firstly increased, peaked under a medium nitrogen rate of 0.177 g/kg and then decreased, but NUE and NHI always decreased with increasing nitrogen levels. NAE in various rice genotypes ever increased with growing process and NUE indicated a descending tendency of elongation stage〉heading stage〉maturity stage〉booting stage. N level influenced rice NAE, NUE and NHI most, followed by genotype, and the both effects were significant at 0.01 level. In addition, the interaction effects of genotype and nitrogen level on rice NAE and NUE were significant at 0.01 level, but not significant on rice NHI. Because the maximum differences of NAE and NUE were found at the elongation stage, it was thought to be the most suitable stage for identification and screening these two paremeters. Therefore, the optimum conditions for identification and screening of rice NAE, NUE and NHI in a pot experiment were the nitrogen rate of 0.157 g/kg at the elongation stage, low nitrogen at the elongation stage, and the nitrogen rate of 0.277 g/kg at the maturity stage, respectively.
文摘A field study to evaluate the impact of different tillage regimes and nitrogen levels on yield and yield components of maize (Zea mays L.), was conducted during autumn 2014 at Students Farm, Department of Agronomy, University of Agriculture, Faisalabad. The experiment was laid out in RCBD (Randomized Complete Block Design), with split plot arrangement having three replications. The experiment was comprised of three tillage regimes (Minimum, Conventional and Deep) and three nitrogen levels viz: 100, 200 and 300 kg•ha<sup>-1</sup>. Urea was used as a source of nitrogen, sulphate of potash as a source of potassium and triple super phosphate as a source of phosphorous. The amount of phosphorous and potash was constant in all the treatments i.e. 125 kg•ha<sup>-1</sup> and 100 kg•ha<sup>-1</sup> respectively. Results of present study are summarized as yield parameters are significantly affected by different nitrogen levels and tillage regimes. Maximum number of plants at harvest (7.93), number of grain rows per cob (17.70), number of grains per row (34.31), number of grains per cob (678.58), and cob weight (187.50 g) were observed in deep tillage at 200 kg•ha<sup>-1</sup> nitrogen application. 1000-grain weight (275.52 g), biological yield (15.66 t•ha<sup>-1</sup>), grain yield (6.16 t•ha<sup>-1</sup>) and dried stalk yield (9.91 t•ha<sup>-1</sup>) were observed maximum in deep tillage at 200 kg•ha<sup>-1</sup> nitrogen application. Harvest index significantly affected by tillage regimes and maximum harvest index (39.58%) were recorded in deep tillage which was statistically at par with conventional tillage (38.83%). It was concluded that higher grain yield of maize can be obtained by deep tillage with the application of 200 kg•ha<sup>-1</sup> nitrogen application under the prevailing conditions of Faisalabad.
文摘为通过不同灌水施氮方式调控干旱区作物收获指数提高资源利用效率,以制种玉米"金西北22号"为供试材料,进行了为期2 a的田间试验。试验采用灌水方式(交替灌水、固定灌水、均匀灌水)与施氮方式(交替施氮、固定施氮、均匀施氮)完全随机组合设计,测定生育期内作物耗水量(evapotranspiration,ET)和成熟期植株的生物量、籽粒产量及其构成(穗长、穗粗、行粒数和千粒质量等)和作物吸氮量,折算收获指数(harvest index,HI)、水分利用效率(water use efficiency,WUE)和氮利用效率(nitrogen use efficiency,NUE)。结果表明,灌水施氮方式只对行粒数有显著影响。ET只受灌水方式影响,交替灌水较其他灌水方式显著减小ET。WUE表现为:灌水方式相同时,交替施氮和均匀施氮大于固定施氮;施氮方式相同时,交替灌水>均匀灌水>固定灌水。玉米的吸氮量、HI和NUE与WUE表现出相似的规律。2013年交替灌水均匀施氮下制种玉米的HI、WUE和NUE最大,较均匀灌水均匀施氮分别增加5.46%、11.41%和19.73%。交替灌水交替施氮(水氮同区)的表现与交替灌水均匀施氮相似。2014年的结果与2013年一致。综上,交替隔沟灌溉均匀施氮和交替隔沟灌溉交替施氮(水氮同区)有利于提高制种玉米的产量和水氮利用效率。
