Analysis of yield combining ability and heterosis of selective lines from the improved maize population MM

【Objective】 To further improve and utilize MM population,elite inbred lines and hybridized combinations were screened,and their breeding potentials,heterotic groups and heterosis pattern of MM population were investigated.【Method】 6 inbred lines(Dan598,WN11,Wu109,Dan599,X104 and Chang7-2) representing the domestic main advantage groups were used as testers,and the combining ability and heterosis of 9 inbred lines selected from the improved maize population MM were analyzed using NCⅡ genetic mating design.【Result】 The relative effects of GCA of the inbred lines 3,4,5,7 and 9 are high and the crosses with high relative effects of SCA for yield per plant were 9×Dan599,6×WN11,3×Wu109,8×WN11 and 1×Dan598.The crosses with high TCA for yield per plant were 9×Dan599,3×Wu109,5×Dan598,4×Dan599 and 7×Dan598 and the crosses with high control heterosis for yield per plant were 9×Dan599 and 3×Wu109.Hybridization between the MM population with WN11 and X104 had no advantage,but hybridization between the MM population with Dan598 and Dan599 had large advantages.【Conclusion】 Inbred lines 3,4 and 5 had higher yields of GCA and can be used for the preparation of the combination.Yields of combinations 9×Dan 599 and 3×Wu109 were higher than the contrast and should be further tested.The MM population is consanguinity similar to the population of Lancaster and Reid yellow dent.It was identified as the population possessing the advantages of both populations,and can be used to build heterotic patterns with Ludahonggu population and P population.