国外Iodent玉米种质WY11对塘四平头群自交系“四287”的改良效果

Improvement Effect of Foreign Iodent Maize Inbred WY11 on Inbred Line “Si 287” of Tangsipingtou Group

采用裂区和NCⅡ试验设计,对Iodent种质WY11、塘四平头群自交系"四287"及其4份遗传改良系进行了耐密性和配合力研究。结果表明:6个自交系中WY11的植株最高(208.2 cm),穗位较高(80.2 cm),秃尖长中等(0.86 cm),空秆率高(2.2%),对密度压力反应较敏感,不耐密植;四287的植株最矮(173.5 cm),穗位较矮(57.8 cm),秃尖短(0.12 cm),空秆率低(0.3%),对密度压力反应不敏感,耐密性好。W87-3的株高、穗位、空秆率、秃尖长均值分别为180.4 cm,64.2 cm,0.4%,0.93 cm,对密度压力反应敏感性弱,具有耐密植潜力;W87-1、W87-2、W87-4,对密度压力反应敏感,耐密性较差。WY11的一般配合力效应值为正向最高(3.57),W87-3和四287的一般配合力效应值较高(3.27,3.22)。在高密度下筛选出四144×WY11和四144×W87-3两个总配合力效应值高的组合,具有高产潜力。W87-3是改良成功的自交系,具有重要的应用价值。

In the study, WY11, Si287 and four improved lines were crossbred with five key inbred lines by NCII mating design. The density-tolerance and combining ability were studied by Split-plot experiment design and Randomized block design. The results showed that inbred line WY11 had the highest plant （ 208.2 cm）, higher ear weight （ 80.2 cm）, middle ear tip length （ 0. 86 cm）, higher empty stem （2. 2%）and lower density-tolerance, and it was very sensitive to density pressure. Si287 had the lowest plant（ 173.5 cm）, lower ear weight （ 57.8 cm）, short tip length （ 0. 12 cm）, lower empty stem （0. 3%）and high density-tolerance, and it was insensitive to density pressure. Plant height, ear height, empty stem and tip length of W87-3 were 180. 4 cm, 64. 2 cm, 0. 4% and 0. 93cm, respectively. It had high density-tolerance and was averagely sensitive to density pressure. Density-tolerance of W87-1, W87-2 and W87-4 was lower. WYll had the highest general combining ability （3.57）, and W87- 3 and Si287 had higher general combining ability （3.27 and 3.22）. Si144×WY11 and Si144×W87-3 had higher total combining ability and potential utilization in maize breeding, and could be used to breed maize variety of high yield and dense planting. W87 -3 was a successful improved line.