摘要：
To determine the effect of wide plant spacing on yield formation of hybrid rice in southern China, a field experiment was conducted in Wuzhou, Guangxi Province in late rice-growing season in 2010. Grain yield, yield components and biomass production of two hybrid rice cultivars (Liangyoupeijiu and II-you 602) were compared between wide (20 x 27 cm) and normal plant spacings (16 x 23 cm). Wide plant spacing produced 10% lower grain yield than normal plant spacing for Liangyoupeijiu, while for II-you 602 the difference was consistent but not significant. For Liangyoupeijiu, wide plant spacing had 12% more spikelets per cm panicle but 13% lower spikelet filling percentage and 4% smaller grain weight than normal plant spacing. Aboveground biomass, harvest index and crop growth rate were less under wide plant spacing than under normal plant spacing by 10, 2 and 9%, respectively. Wide plant spacing is unsuitable for hybrid rice production in southern China.
摘要：
为探讨南方双季超级稻对氮、磷、钾养分的吸收积累及利用规律,于2008—2010年在湖南长沙和浏阳以超级早稻陆两优996、陵两优268和超级晚稻丰源优299、天优华占为材料进行大田定位试验,比较了“三定”栽培、免耕摆栽和传统栽培条件下双季超级稻不同生育期植株体内氮、磷、钾吸收积累特点及氮肥利用率。与传统栽培相比,“三定”栽培双季超级稻生长前期(分蘖中期)氮、磷、钾的吸收量较低,幼穗分化期差异小,而齐穗期(早季平均为10.71、2.23和11.82 g m~(-2),晚季平均为12.25、2.69和16.37 g m~(-2))和成熟期(早季平均为13.61、3.01和13.71 g m~(-2),晚季平均为17.16/3.31和18.31 g m~(-2))较高;氮肥的偏生产力(平均为53.40 kg kg~(-1))、吸收利用率(平均为55.98%)、农学利用率(平均为22.27 kg kg~(-1))较高,分别提高29.00%/88.92%和46.67%。免耕摆栽双季超级稻不同生育时期氮、磷、钾的吸收特点与“三定”栽培相似,但其氮肥的偏生产力、吸收利用率和农学利用率(平均为50.24 kg kg~(-1)/52.75%和19.33 kg kg~(-1))分别比“三定”栽培降低6.29%/6.12%和15.19%。由此可见,双季超级稻生产采用“三定”栽培技术有利于提高氮肥利用率。
关键词：
Direct seeding;Panicle number;Panicle size;Physiological factor;Super hybrid rice
摘要：
Super hybrid rice Liangyoupeijiu was grown by transplanting (TP) at a spacing of 20 cm x 20 cm with one seedling per hill and by direct-seeding (DS) at a seeding rate of 22.5 kg ha(-1) (about 120 seeds m(-2)) in Changsha, Hunan Province, China in 2004-2010. Grain yield and yield components were measured each year, and some physiological factors were determined in 2009. There was no significant difference in mean grain yield across years between DS and TP. DS produced more panicles per m(2) but less spikelets per panicle than TP. The differences in number of spikelets per m(2), spikelet filling percentage and grain weight between DS and TP were not significant. A large number of panicles per m(2) in DS was derived from the increased number of tillers per m(2) rather than increased rate of panicle-bearing tillers, and the number of tillers per m(2) was mainly determined by the number of hills per m(2) because the number of tillers per hill was small in DS plants. Tillering rate, tillering duration as well as carbohydrate and nitrogen metabolism were critical to the reduced number of tillers per hill in DS. In DS plants with fewer spikelets per panicle, the numbers of primary branches and secondary branches per panicle, spikelets per primary and secondary branches, and also panicle length and spikelets per unit panicle length were smaller. These differences were attributed to the smaller source leaf size as well as lower root activity and the nutritional status at panicle initiation.
关键词：
super hybrid rice;yield;panicle number;panicle size
摘要：
Chinese super hybrid rice breeding project has developed many new varieties with great yield potential. It is controversial which yield component should be emphasized in super hybrid rice production. The present study was conducted to compare super hybrid rice with common hybrid and super inbred rice and analyze contributions of yield components to grain yield of super hybrid rice under experimental conditions, and evaluate relationships between grain yield and yield components of super hybrid rice in farmer’s paddy fields. Field experiments were done in Changsha, Guidong, and Nanxian, Hunan Province, China, from 2007 to 2009. Eight super hybrid varieties, one common hybrid variety, and one super inbred variety were grown in each location and year. Rice production investigation was undertaken in high-yielding （Guidong）, moderate-yielding （Nanxian）, and low-yielding （Ningxiang） regions of Hunan Province, China, in 2009. Grain yield and yield components were measured in both the field experiments and rice production investigation. Super hybrid rice varieties outyielded common hybrid and super inbred varieties across three locations and years. Yield potential has been increased by 11.4% in super hybrid rice varieties compared with common and super inbred varieties. The higher yield of super hybrid varieties was attributed to improvement in panicle size. Panicles per m2 had the highest positive contribution to grain yield with the exception under yield level of 10.0 to 12.0 t ha-1, and was positively related to grain yield in farmer’s field at all of the high-, moderate-, and low-yielding regions. Our study suggests that panicle per m2 ought to be emphasized in super hybrid rice production.
摘要：
为探讨南方双季稻区超级稻高产栽培技术，于2008-2010年在湖南长沙和浏阳以超级早稻陆两优996、陵两优268和超级晚稻天优华占、丰源优299为材料进行大田定位试验，比较了“三定”栽培、免耕摆栽和传统栽培下双季超级稻的产量形成特点和生理特性。与传统栽培相比，“三定”栽培齐穗期的颖花伤流量、根系氧化力、根冠比、叶面积指数及籽粒结实期剑叶的光合速率较高，齐穗后剑叶SPAD值下降缓慢、干物质积累量大，有效穗数和每穗粒数多，早季平均产量为7.18 t hm~(-2)，增产11.68%，晚季平均产量为8.39 t hm~(-2)，增产7.41%；免耕摆栽干物质积累量大、有效穗数多，但其收获指数、每穗粒数和结实率居劣势，使其单季增产效果不显著。由此可见，南方双季超级稻在“三定”栽培下后期生理优势明显，产量构成因子协调，增产效果显著。
作者机构：
Crop Physiology,Ecology,and Production Center,Hunan Agricultural University,Changsha,Hunan 410128,Ch;Crop Physiology and Production Center(CPPC),MOA Key Laboratory of Crop physiology,Ecology and Cultiv;Crop and Environmental Sciences Division,International Rice Research Institute(IRRI),DAPO Box 7777,M
会议名称：
全国第十四届水稻优质高产理论与技术研讨会
会议时间：
2011-08-01
会议地点：
长沙
会议论文集名称：
全国第十四届水稻优质高产理论与技术研讨会论文集
关键词：
Alternate wetting and drying irrigation;Grain filling;Grain yield;Nitrogen rate;Water use efficiency
摘要：
Rice production in Asia is increasingly constrained by water limitation as a consequence of global water crisis.One of the technology options that can help farmers cope with water scarcity at the field level is alternate wetting and drying (AWD).Nitrogen (N) is also an important factor which often interacts with water and influences rice growth.
作者机构：
College of Biological Science and Technology,Hunan Agricultural University,Changsha,Hunan 410128;Institute of Rice Research,College of Agronomy,Hunan Agricultural University,Changsha,Hunan 410128;Research Center of Modernization of Chinese Herbal Medicines,College of Chemistry and Chemical Engin;Institute of Land Utilization and Information Technology,College of Resources and Environment,Hunan;Huilongxu Town,Jiangyong County,Hunan province
会议名称：
全国第十四届水稻优质高产理论与技术研讨会
会议时间：
2011-08-01
会议地点：
长沙
会议论文集名称：
全国第十四届水稻优质高产理论与技术研讨会论文集
关键词：
aromatic rice;soluble protein;L-proline;soil total nitrogen;GC-MS
