Genetic Study Of No-Reid Improved Line Based On Maize DH Breeding Technology

Corn has gradually become the most important food crop in the world in recent years.Due to its wide use,high-yield characteristics and important role and status,corn has been able to influence the social and economic development of a country,and its strategic position is outstanding.Corn DH breeding technology,that is,corn double haploid sports technology,is a new type of genetic improvement technology that has been rapidly developed at home and abroad in recent years.Compared with conventional methods,the breeding cycle is short,which significantly improves the breeding efficiency.Therefore,in this experiment,10 No-Reid improved lines were bred by maize DH breeding technology.After screening and identification,9DH151,9DH608,9DH81,J9D207 and extroversion lines PHB1 M,PH4CV were selected as fathers,and J1049,J1598,J1595,J1033 were selected.With the introduction of PH6 WC as the female parent,30 hybrid combinations(6 × 5)were designed according to the design of NC?.At a density of 60,000 plants / hectare,the heterosis and combining ability of the main agronomic traits were studied.The research results are as follows:1.The average dominance results show that under the density of 60,000 plants / ha,the average yield advantage of the combination 9DH151 × J1598 plot is the highest,at 141.25%,and the combination 9DH81 × J1598 is poor.The result of over-standard advantage shows that the combination 9DH151 × J1598 is also the highest at 122.29%,and the combination PH4 CV × J1049 performs poorly.It is comprehensively shown that the best combination of plot yield advantage is 9DH151 × J1598,which has obvious advantage of increasing yield.2.The results of general combining ability analysis showed that,under the density of 60,000 plants / ha,the maternal inbred line with the highest yield combining ability effect value was J1595;the male inbred line with the highest combining ability effect value was 9DH151.The maternal inbred line with the highest combining ability effect value for panicle weight is J1595;the male inbred line with the highest combining ability effect value is 9DH151.The maternal inbred line with the highest combined effect value of 100-grain weight is J1033;the male inbred line with the highest combined effect value is J9D207;the maternal inbred line with the highest combined effect value of panicle length is J1595;Generally,the male parent inbred line with the highest effect value of combining ability is 9DH81.Comprehensive analysis results show that the female inbred line J1595 and the male inbred line 9DH151 are the best.3.The result of special combining ability shows that under the density of 60,000 plants / hectare,the combination with the highest special combining ability in plot yield is 9DH151 × J1598,and the combination with the highest combining ability of ear thickness and ear weight is also 9DH151 × J1598,with special combination of ear length The combination with the highest force is PH4 CV × J1595,and the combination with the highest 100-grain weight special combination is 9DH151 × J1049.In summary,the combination 9DH151 × J1598 is the best.4.Analysis of genetic parameters showed that traits such as shaft thickness and 100-grain weight were mainly controlled by additive gene effects,while ear length and weight were mainly controlled by non-additive gene effects.