两种插秧密度下不同穗型水稻品种耐密性研究

摘要

To study the density-tolerance of semi-erect panicle type in rice,14 Japonica varieties,belonging to 3 spike types,were grown in the two densities level (30 cm,25 cm).The results show that,in low density,leaf area index (LAI) of the semi-erect panicle type varieties was significantly lower than that in the curved panicle type varieties ,efficient leaf area of semi-erect panicle type variety was significantly greater than that of the upright rod spike type and curved panicle type varieties .During increasing the density ,LAI in semi-erect panicle type varieties show little changed ,but the high efficient leaf area was increased significantly.In high density ,plant height and ear length in semi-erect panicle type varieties were significantly reduced compared with the curved panicle type varieties .Grain density in semi-erect panicle type varieties was significantly lower than that in the upright rod spike type cultivars .In semi-erect panicle type,flag leaf and top 2 leaf length was significantly longer than that in the upright rod spike type cultivars ,leaf width was significantly wider than that in the curved panicle type varieties.With increasing the density ,individuals of semi-erect panicle type tend to conver-gence.In high density ,semi-erect panicle type show higher lodging resistance than the curved panicle type varieties ,higher seed setting rate than the upright rod spike type cultivars ,and higher milled rice rate and yield.Taken together ,semi-erect panicle type is more den-sity tolerant than two other spike types ,which attributed to,suitable ear rise and plant height (85 cm~90 cm),increasing individuals convergence and effective leaf area ,more panicle number per square meters and lodging resistance.Thus, the total yield of semi-erect panicle type is significantly increased in high density ,which is the key and base for high density growth cultivation.%以14个不同穗型常规粳稻品种为材料，在30 cm、25 cm两种密度水平下种植，研究半直立耐密型常规粳稻增加密度后主要性状因子的配置及耐密性。结果表明，半直耐密型品种叶面积指数极显著低于弯穗型品种，半直立耐密型品种的高效叶面积极显著地高于直立棒穗型品种和弯穗型品种。增加密度后半直立耐密型品种叶面积指数增加比例小，高效叶面积增加显著。株高显著低于弯穗型品种，穗长极显著低于弯穗型品种，着粒密度极显著低于直立棒穗型品种。剑叶和倒2叶长显著长于直立棒穗型品种，叶宽显著宽于弯穗型品种。增加密度后个体更趋于收敛。半直耐密型品种增加密度后抗倒性强于弯穗型品种，结实率高于直立棒穗型品种，出米率好，产量高。半直耐密型品种穗位上升（半直立），株高降低（85 cm～90 cm），增加密度后个体收敛，高效叶面积增加，是增加平方米穗数，增强抗倒性，提高产量和出米率的关键，是窄行增密或减肥增密配套栽培的基础。图3，表2，参8。