Study On Heterotic Grouping Of Maize Inbred Lines

It’s significant to group maize inbred lines correctly and set up correspondingheterotic patterns in maize breeding.At present, too many clusters are divided in manystudies of grouping maize inbred lines,it’s adverse to simplify heterotic patterns andincrease breeding efficiency.In this study, Simple sequence repeat(SSR) was used todetect genetic variation among116maize inbred lines and6testers. The results weresummarized as follows:1.The optimized SSR marker detection system was established by selecting SSRprimers,optimization design of PCR system and sifting primers’ optimum annealingtemperature. The optimum SSR reaction system in maize was as follows:total volumewas10μL,10×PCR buffer(with Mg2+)1.0μL, dNTP(2.5mmol/Leach)0.3μL,primers(10μmol/L)0.3μL each,DNA60ng,Taq DNA polymerase0.5U.The optimum annealing temperature of primers were sifted by gradient PCR.2.122maize inbred lines were fingerprinted with70SSR markers.A total of257alleles were detected.The average alleles per locus were3.67with a range from2to7.The mean value of the polymorphism information content(PIC) was0.597with arange from0.252to0.817.The genetic similarity (GS) was estimated with an averagevalue of0.660,which was from0.482to0.902.3.By UPGMA (unweighted pair group method arithmetic average),122inbredlines could be classified into5clusters which could be simplified into SS (I,II) andNSS(III,IV,V) heterotic groups.