栽植密度和播期对水稻广两优5号产量形成的影响

吴建平　陈少愚　李阳　赵锋　徐得泽　蔡海亚　游艾青　万晟杰　费长亮　程建平　张旅峰　章桃娟　皮楚舒

摘要：考察了栽植密度、播期对广两优5号产量形成的影响。结果表明，广两优5号栽植密度为22.5万穴/hm2、播期在4月25日产量最高。广两优5号随栽植密度增大，茎蘖数峰值提高、有效穗数增多、每穗实粒数减少；随播期推迟，该组合分蘖峰值滞后，无效分蘖增多、穗实粒数减少。4月25日后播种、栽植密度22.5万穴/hm2时，广两优5号产量最高可达753.3 kg/667 m2；5月5日及以后播种，广两优5号产量显著降低。广两优5号在湖北省种植适宜播期为4月中下旬，栽植密度应保持22.5万穴/hm2。

关键词：杂交水稻；广两优5号；栽植密度；播期；产量形成

中图分类号：S511 文献标识码：A 文章编号：0439-8114（2015）24-6157-04

DOI：10.14088/j.cnki.issn0439-8114.2015.24.013

Abstract：To investigate yield formation factors of Guangliangyou No.5 under different planting density and sowing date， the result showed that Guangliangyou No.5 under cultivated density of 22.5×104 hill/hm2 or its sowing date on April 25 could gain the highest yield. With the increase in plant density， not only that tiller numbers peak value of rice was increased， but also unavailable tiller increased， so panicle number and grain number per spike were reduced. When sowing date was postponed， tiller peak value appearance date was delayed， the unavailable tiller increased and the number of grains per spike was reduced. This result concluded that the rice production can be up to 753.3 kg/667 m2 when its planting density is 22.5×104 hill/hm2； the rice should be seeded after the May 5th， whenever the sowing date were earlier or later， the yield was decreased. As a high-yield and late maturity hybrid rice varieties， Guangliangyou 5 is suitable to be seeded in Hubei province in mid-to-end of April， and the planting densities should be kept around 22.5×104 hill/hm2.

Key words： hybrid rice； Guangliangyou No.5； planting density； sowing date； yield formation

两系杂交中稻广两优5号是由湖北省农业科学院粮食作物研究所采用广占63-4S与香型优质恢复系香5配组而成的优质高产新组合。母本为广占63-4S（从江苏里下河地区农业科学研究所引进）；父本为香5（用扬稻6号与鄂中5号杂交，再与中国香稻复交，经多代定向选择，育成的香型优质恢复系）。该组合融合了父本的三个亲本的突出优点，遗传了中国香稻的香味、鄂中5号的米质和扬稻6号的丰产性，适于湖北省鄂西南山区以外的稻瘟病无病区或轻病区作中稻种植。为追求单季超高产，生产上往往采取密植和“大肥、大水、大药”等管理措施，不仅增加了农田面源污染、病虫害、倒伏等风险，而且降低资源利用效率和稻米品质[1，2]。

栽植密度是构建、优化水稻群体质量的起点和基本措施之一[3]，合理的播期是充分利用光温资源，充分发挥土壤生长潜力，保证个体的正常发育和群体的协调发展，进而获得高产[4，5]，同时规避不利气候条件的重要措施。……