小麦穗下节性状与灌浆速率及产量相关因素的关系

Relationship of peduncle traits to grain-filling and yield-related factors in wheat

穗下节是连接旗叶和穗的部位.为明确穗下节性状与灌浆特性及产量相关因素的关系,分析91份西南小麦材料的穗下节性状和千粒重之间的相关性,进一步以筛选出来的3种穗下节长度、粗度的18份材料进行灌浆特性和产量相关因素差异分析.结果显示:91份材料的穗下节长度变幅为22.05-52.75 cm,粗度变幅为2.33-3.63 cm,体积变幅为121.10-403.52 cm^(3),变异类型丰富;穗下节长度与粗度、穗下节长度、粗度、体积与千粒重均线性回归显著,呈正相关关系.穗下节长度最长类型灌浆特性综合表现最好,其中平均灌浆速率和最高灌浆速率分别为0.33、2.78 g/d;穗下节粗度最粗与中等类型灌浆特性无明显差异,均优于最细类型灌浆速率.从产量相关性状看,穗下节长度最长类型平均单株粒重、千粒重分别为14.87、52.44 g,均显著高于其余两种类型;穗下节粗度中等类型综合表现优于其余两种类型.因此,综合考虑灌浆特性、产量相关因素,在西南地区选择穗下节最长、粗细中等的材料有助于选育灌浆特性、产量表现优异的小麦新品种;上述结果可为西南地区小麦的株型改良与高产选育提供参考依据.(图1表3参36)

The peduncle is the joining path between the leaf and spike.The relationship of peduncle traits to grain-filling and yield-related factors needs to be characterized.We observed the relationship between peduncle traits and the thousand-grain weight of 91 wheat varieties in Southwest China via correlation analysis.Eighteen wheat genotypes selected from 91 wheat varieties were divided into three types based on peduncle length and diameter.The characteristics of the grain-filling and yield-related factors of the three types were investigated.Variation was pronounced among 91 wheat varieties,with peduncle lengths ranging from 22.05 to 52.75 cm,diameter from 2.33 to 3.63 cm,and volume from 121.10 to 403.52 cm^(3).Peduncle length,diameter,and volume were significantly correlated with thousand-grain weight in a linear regression model.The grain-filling characteristics of the longest peduncle type were the best,of which the mean grain-filling rate and max grainfilling rate were 0.33 and 2.78 g/d,respectively.No significant difference was observed between the thickest peduncle and the intermedium peduncle type of grain-filling characteristics.However,both were better than the thinnest type.Concerning yield-related factors,the average grain weight per plant and thousand-grain weight of the longest peduncle length type was 14.87 g and 52.44 g,respectively,which were significantly higher than the other two types.The comprehensive performance of the middle diameter peduncle was better than those of the other two types.Therefore,based on filling characteristics and yield-related factors together,wheat materials with the longest and middle diameter peduncle should be selected to quickly and effectively obtain wheat varieties with excellent grain-filling characteristics and yield performance in Southwest China.These experiments provide useful information for improving plant type and yield potential in wheat breeding programs in Southwest China.