Analysis On Maize DH Lines Heterosis And Genetic Characteristics, Research On Haploid Genetic Separation

Two aspects of genetic studies on Maize DH lines and haploid genetic separation characteristics were studied in this paper.Firstly,on the basis of Reid class group main germplasm PH09B×PH6WC bred 6 DH lines DH1-DH6 as female parents,Non-Reid group backbone inbred lines PH4 CV,J9D207,J1881 and Dom group backbone inbred lines S122,Chang7-2 as male parents,mated design 30 crosses combinations by NCII,under the density of 60000 plants/hm2,studies heterosis,combining ability and genetic parameter of DH lines.Through the yield performance of cross combinations,evaluated the potential applications of DH lines.And the inheritance of plant height,ear height and hundred-grain weight of maize was tested by using genetic models.Secondly,cross combinations J9D207×KWMM31,J1828×KWMM31,M5972×KWMM31 as the female induction base material,high frequency induction line JS9 as the male parent,hybrid induced haploid,in combination with SSR markers,analysis the population genetic separation characteristics of the haploid on molecular level.The results are as follows:The heterosis results of six DH lines showed that,under the density of 60000 plants/hm2,the highest acre yield average-heterosis and check-heterosis(Xianyu335)of 30 cross combinations is DH2×PH4CV,is 127.72%,16.59%.The second is DH3×PH4CV,average-heterosis and check-heterosis is127.35%,15.66%.We can do further identification on stable yield ability and high yield ability of these two potential advantage combinations.The average-heterosis of ear high,ear weight and cob weight is obvious.The combining ability analysis results of six DH lines showed that,the highest general combining ability effect value inbred line of yield is DH2,every other traits general combining ability effect value is also higher.Based on the analysis of the specific combining ability and total combining ability effect,cross combinations DH2×PH4CV and DH2×J1881are high yield advantage.So we think that at first,the inbred line DH2 is more potential in improving the yield character.The genetic model test showed that,the inheritance of ear height of maize was consistent with additive-dominance genetic model,plant height and hundred-grain weight of maize was consistent with additive-dominance-epistatic genetic model.The genetic parameter analysis results of six DH lines showed that,plant height,ear height,stem diameter,ear length,ear coarse,cob weight,bare top length,ear row number and hundred-grain weight should focuses on the use of general combining ability;The line grain number,ear weight and yield should focuses on the use of special combining ability.Ear row number,plant height,ear height,ear length,bare top length,Hundred-grain weight and stem diameter should be selected at the early generation;Ear coarse,ear weight,line grain number and acre yield should be selected at the late generation.The SSR marker research of haploid segregation distortion shows that,J1828×KWMM31 and M5972×KWMM31 as the base material,in the process of hybrid induced haploid,The segregation ratio in accordance with Mendel separation rule(1:1).Nevertheless,J9D207×KWMM31 as the base material,in the process of hybrid induced haploid,in41 SSR markers,there are 3 markers located in the maize chromosome 8,preference for female parent inbred lines J9D207,may constitute the hot spots of segregation distortion,the whole haploid group is also exist segregation distortion.