The Genetic Diversity And Heterotic Group Classification Of Maize Inbred Line In Spring Sowing Medium-late Maturing Area In Shanxi Based On SSR Marker Summary

Maize is a high yield and multi-purpose crop which plays an important role in Chinesenational economy. It is a dominant crop in Shanxi province with its leading cultivationacreage, unit yield and total output. Shanxi is a long and thin area stretching6.3Latitudefrom the south to north and4.2Longitude from the east to west. Within the territory thereare mountains ups and downs and show an elevation difference about1800meters. Theclimate in Shanxi is extremely diverse and ecosystem-type complex. The maize cultivationarea in Shanxi are divided into four four kinds of ecosystems, including spring sowingextreme of spring sowing extreme early maturing, spring sowing early maturing, springsowing medium late maturing and summer sowing medium early maturing. Among themthe spring sowing medium-late maturing has the largest acreage, the highest unit yield andaround half output accounting for the total in the province. It is considered critical for theevolution of the agricultural industry that institutes and researchers develop the capability ofgenetic improvement for increasing the yield and quality of maize.As an important material basis for genetic improvement, crop germless resources arethe key to promote breeding efficiency. On this purpose, molecule marker technology SSRwas employed and6domestic inbred lines as standard inspection seeds, genetic diversityanalysis and heterotic group classification was conducted for32inbred lines of18certifiedvarieties in spring sowing medium-late maturing area in Shanxi. The results are thefollowing:(1) The genetic diversity of maize inbred lines in spring sowing medium latematuring area in Shanxi was studied based on SSR marker. The results showed as thefollowing: Total210alleles in32maize lines were detected with an average of5.2rangedfrom2to11per locus by40SSRs covered the entire maize genome. Mean PIC was0.67ranged from0.41to0.84. Mean MI was2.94ranged from0.82to5.14, and mean NE was3.42ranged from1.70to6.39.(2) Total35rare alleles and31unique alleles were identified.35rare alleles weredetected at24loci, at bnlg2331locus,4alleles were identified. At19loci there were rare alleles, so there were total31unique alleles were identified. At mmc0191locus and phi126locus,4rare alleles were identified, which suggested that genetic diversity in spring sowingmedium late maturing maize area was fairly rich.(3) Genetic distances of the32inbred lines were measured: The32maize inbred lineswere clustered into four groups through UPGAM cluster analysis method. In the Group I(BSSS germplasm)，there were3subgroups. As for the1stsubgroup, there were standardgermplasm B73, but no experimental material; In the2nd subgroup(PA germplasm)，therewere6material, and in the3rd subgroup (Lancast germplasm)，there were2materials; InGroup II(lvdahonggu germplasm)， there were13materials. For the Group III (PBgermplasm)， there were7materials and the Group IV(tangsipingtou germplasm)4materials.