适宜机直播的优质籼稻品种筛选及其评价指标体系

Selection of Indica rice varieties and its evaluation index system for mechanized direct-seeded rice

【目的】筛选适宜机直播的优良籼稻品种,建立适宜机直播的籼稻品种评价关键指标体系,为适宜机直播专用籼稻品种选育及应用提供参考。【方法】以近年来选育的30个优质籼稻品种为试验材料,于2017年在贵州省湄潭县进行机械化精量穴直播试验,以成苗性、抗倒性及丰产性为核心指标,筛选适宜机直播的籼稻品种,并系统研究其生长发育特性。【结果】机直播条件下各水稻品种的产量介于6.1~10.5 t/ha,单位面积成苗数介于35.8~50.6株/m2,倒伏指数介于101.6%~260.6%,以产量、单位面积成苗数和倒伏指数进行聚类分析,筛选出川优8377、蓉18优2348、德优4727、晶两优534、宜香优2115、晶两优华占、Y两优1号和F优498等8个适宜机直播籼稻品种,其产量均>8.2 t/ha,单位面积成苗数均>48.0株/m2,倒伏指数均<140.0%,其余22个品种为不适宜机直播类型。两种类型水稻品种的生长发育特性具有明显差异,且适宜机直播类型的水稻品种分蘖成穗率均>65.0%,收获指数均>0.45,茎秆基部大于4 cm的第1节间抗折力均>1500.0 g,全生育期均<150 d,穗粒数均>140.0粒,结实率均>70.0%。【结论】F优498等8个优质籼稻品种适宜机直播,该类品种总体上表现出单位面积成苗数高、植株分蘖力中等但成穗率较高、收获指数较高、茎秆抗倒伏能力较强、生育期适中、穗型较大且籽粒充实良好、产量高等特点。

【Objective】In order to screen suitable rice varieties for mechanized direct-seeded rice and establish its key index system for evaluation of the suitable rice varieties,and to provide theoretical basis and technical support for selection and breeding of the suitable rice varieties for mechanized direct-seeded rice.【Method】The seedlings per unit area,lodging index and grain yield of rice were used as common indicators to select the suitable varieties for mechanized directseeded rice with 30 high quality Indica rice varieties selected in recent years were used as materials at the middle altitude area of Guizhou(Meitan)in 2017.The rice varieties suitable for mechanized direct-seeding were selected and their growth characters were studied.【Result】The grain yield of mechanized direct-seeded rice was between 6.1 and 10.5 kg/ha,and the seedlings per unit area was between 35.8 and 50.6 seedlings per m2,and the lodging index was between 101.6%and 260.6%.The cluster analysis was performed based on grain yield,seedlings per unit area and lodging index.Eight rice varieties including Chuanyou 8377,Rong 18 You 2348,Deyou 4727,Jingliangyou 534,Yixiangyou 2115,Jingliangyouhuazhan,Y Liangyou 1,F You 498,which had the grain yield>8.2 t/ha,seedlings per unit area>48.0 seedlings per m2,and lodging index<140.0%,were suitable for mechanized direct-seeded rice.The remaining 22 rice varieties including were unsuitable for mechanized direct-seeding.There was large difference in the growth and development characteristics of the two types of rice varieties.The suitable rice varieties for mechanized direct-seeding should be based on the following characteristics:the percentage of available tiller>65.0%,harvest index>0.45,the breaking-resistant strength of the basal internode(above 4 cm)>1500.0 g,the full growth and development period<150 d,grain number per panicle>140.0,seed-setting rate>70.0%.【Conclusion】Eight high-quality Indica rice varieties such as F You 498 are suitable for mechanized direct-seeded rice.This type of varieties generally shows more seedlings per unit area,medium plant tillering capacity with high percentage of available tiller,high harvest index,strong resistance to lodging,moderate growth period,large panicle with good grain filling characteristics,and high grain yield.