蚕豆6×6双列杂交子代主要性状的遗传效应分析

Genetic Analysis of Main Traits of Cross Combinations After 6×6 Diallel Crossing in Faba Bean

为提高蚕豆优势组合的选配效率,以6个蚕豆材料(P1~P6)为亲本,采用Griffing完全双列杂交配制30个组合,分析亲本和F1的9个主要农艺性状的杂种优势、配合力和遗传力。结果表明,蚕豆产量相关农艺性状的杂种优势明显,分枝数、单株荚数、单株粒数、每荚粒数、百粒重和单株产量的超亲优势为正值,株高、始荚高和主茎节数的超亲优势为负值。配合力效应分析表明,P1和P2为选育大粒高产的优良亲本,P1×P2和P4×P6符合高产的育种目标,P2×P5和P2×P6符合大粒的育种目标;遗传力分析表明,百粒重、每荚粒数和单株粒数的广义遗传力和狭义遗传力均较高,可以相对稳定地遗传给后代,且这3个性状主要受加性效应控制,适宜进行早代选择,其他性状主要受非加性效应影响;主要性状与单株产量的相关分析表明,蚕豆育种应将单株荚数和单株粒数作为重点目标;通径分析表明,在育种过程中应重点关注分枝数、株高、百粒重、每荚粒数等农艺性状。本研究为蚕豆育种进程中的亲本选配和后代选择提供了一定的理论依据。

In order to improve the efficiency of selecting elite combinations of faba bean(Vicia faba L.),six parental lines(P1-P6)were used to develop 30 hybrids by Griffing complete diallel crossing design,and nine agronomic traits were evaluated to analyze heterosis,combining ability and heritability.The results indicated that the 30 F1 hybrids showed distinct heterosis for yield traits.Among nine traits,the number of primary branches,pods per plant,seeds per plant,seeds per pod,100-seed weight,and seed weight per plant were improved over the best parent,but the traits of plant height,first fruiting height,and nodes number of the main stem conferred negative parent values.Analysis of combination ability showed that P1 and P2 with high general combination ability(GCA)were the optimal lines for selecting high-yield varieties with large grains,and the crosses P1×P2,P4×P6,P2×P5 and P2×P6 were determined as the excellent combinations based on special combination ability(SCA).The high value of broad sense heritability and narrow-sense heritability for 100-seed weight,seeds per pod and seeds per plant indicated these traits were mainly controlled by additive effects,which could be inherited relative stablely.That meant that the three traits were more suitable for being selected at early generations other traits were controlled by non-additive effects.The coefficient between major traits and yield per plant suggested pods per plant and seeds per plant should be selected the target traits in faba bean breeding.In addition,the result of path analysis further emphasized that faba bean breeding should be focused on the number of primary branches,plant height,100-seed weight and seeds per plant.These results will provide the theoretical basis for parents and off-spring selection in faba bean breeding process.