低纬高原和高纬平原粳稻主要耐冷相关性状的遗传分析

 利用3个来自云南低纬高原的粳稻品种和3个来自日本、韩国高纬平原地区的粳稻品种，以及应用完全双列杂交获得的30个F1为试验材料，利用加性 显性 母体效应（ADM）遗传模型，在5种不同生长环境下，对单株结实率、特定结实率、穗抽出度和抽穗天数等4个主要耐冷相关性状进行了遗传分析。4个耐冷相关性状中，单株结实率和特定结实率主要受基因型×环境互作效应的影响，不存在母体效应；单株结实率和特定结实率以互作广义遗传率最高，分别为63.5%和56.5%。单株结实率与特定结实率间的表现型、基因型、加性和显性效应的相关均达到极显著水平，相关系数介于 0.717～1.000；单株结实率与穗抽出度间的表现型、基因型、加性和显性效应相关也均达到极显著水平，相关系数介于0.161～0975。穗抽出度的变异系数变幅最大，穗抽出度也是耐冷性鉴定评价中不可忽视的重要性状。穗抽出度和抽穗天数以广义遗传率为最大，分别为59.6%和81.4%。抽穗天数主要受遗传主效应控制，受环境的影响最小。低温胁迫是选择培育耐冷性品种的必要条件，一品稻（Ilpumbyeo）×昆明小白谷是培育强耐冷性粳稻新品种的最优组合。

Genetic Analysis of Main Characteristics Related to Cold Tolerance in japonica Rice from Low-Latitude Plateau and High-Latitude Plain

Six varieties including three varieties from low-latitude plateau in Yunnan Province, China, and the other three from high-latitude plain in Japan and Korea and their 30 F1 crosses obtained by complete diallel crossing were planted under five different environments. The genetic model of additive-dominance-maternal effects (ADM) was applied to genetic analysis on four traits related to cold tolerance, i.e. spikelet fertility (SF), specific spikelet fertility (SSF), panicle exsertion (PE) and days to heading (DH). The results showed that SF and SSF were mainly affected by interaction effect between genotype and environment, with little maternal effect. Interaction heritability in broad sense between genotype and environment for SF and SSF were 63.5% and 56.5%, respectively, the highest compared with other effect values for heritability. Correlations between phenotype, genotype, additive and dominant effects of SF and those of SSF reached significant level with the correlation coefficients ranged from 0.717 to 1.000. Correlations between phenotype, genotype, additive and dominant effects of SF and those of PE also reached significant level with the correlation coefficients ranged from 0.161 to 0.975. The range of coefficient of variation varied with the traits, and that of PE were the maximum compared with other three traits. Hence PE was also a valuable trait in evaluation of cold tolerance. As for to PE and DH, their broad-sense heritabilities were 59.6% and 81.4%, respectively, the biggest compared with other effect values for heritability. DH was mainly controlled by genetic effects, with the least influence by environmental conditions. The low-temperature stress should be one of the essential conditions to breed varieties with cold tolerance. A cross between Ilpumbyeo and Kunmingxiaobaigu was an optimum combination for breeding new cold tolerant japonica variety at the booting stage.