| Corner stone parents is important for breeding and creation of winter wheat.Genetic diversity is important for wheat breeding program. To assess the genetic diversity of Aimengniu and its derivatives from the agronomic traits, quality traits, HMW-GS and SSR. The results showed that there was abundant diversity among different varieties, which could afford reference in wheat breeding.1 Genetic diversity of Aimengniu and its derivatives was studied with agronomic traitsGenetic diversity in 91 accessions of Aimengniu and its derivatives was assessed using seven agronomic traits .The results shown that heading dates were from 184d to 223d with an average 195d , Coefficient of variations and diversity indexe of it were 2.30%, 1.23 respectively. Flower dates 196d-233d with an average 204d , Coefficient of variations and diversity indexe of it were 2.06%, 0.98 respectively, plant height 60-120cm with an average 85.4cm , Coefficient of variations and diversity index of it were 13.20%, 1.95 respectively, spike length 6.2-16cm with an average 9.67cm , Coefficient of variations and diversity index of it were 16.0%, 1.94 respectively, Flag leaf area 18.77 -52.46cm2, Coefficient of variations and diversity index of it were 24.10%, 1.98 respectively, Length below spike were 3.53 -21.3cm, Coefficient of variations and diversity index of it were 33.10%, 2.06 respectively, 1000-grain weight 21.9 -58.7g with an average 42.09g, Coefficient of variations and diversity index of it were 15.40%, 2.03 respectively, Except of Heading date and Flower date, Coefficients of variations and diversity indexes of agronomic traits had significant range, which indicate genetic difference among them was significant.2 Genetic diversity of Aimengniu and its derivatives was studied with quality traitsFor six quality traits , diversity indexes were 1.86-2.00,coefficients of variations for six quality traits were 7.11%-35.21%,and were more than 20% for three farinogram parameters. Coefficients of variations and rang indicated that genetic difference among them was significant. protein content were from 10.05% to 14.60% with an average 11.68% , Coefficient of variations and diversity indexe of it were 7.11%, 2.00 respectively. wet gluten content 28.30-52.80 % with an average 38.63% , Coefficient of variations and diversity indexe of it were 12.72%, 1.98 respectively, SDS-sedimentation value, 20.71-59.00ml with an average 33.02ml , Coefficient of variations and diversity indexe of it were 19.53%, 1.93 respectively, Dough development time 1.90-6.30min with an average of 3.16min , Coefficient of variations and diversity indexe of it were 22.47%, 1.94 respectively, Dough stability time 1.30-6.10min,Coefficient of variations and diversity indexe of it were 35.21%, 1.87 respectively, Dough breakdown times were 2.80-9.00min, Coefficient of variations and diversity indexe of it were 25.00%, 1.86 respectively.Except of SDS-sedimentation value (33.02ml) and wet gluten content (38.63%) , other quality traits indexs were small which indicated dough rheological properties and quality of dough gluten of Aimengniu and its derivatives were not good.3 HMW-GS component analysis of Aimengniu and its derivativesThe diversity among 91 accessions of Aimengniu and its derivatives was evaluated by employing the method of SDS-PAGE. It showed that :â‘ At the Glu-A1 locus, the frequency of 1 subunits was highest (51.65%),secondly is Null subunit (42.86%). The 2* subunit was rare, only 5.49%.â‘¡At the Glu-B1 locus, 7+8 subunit occupied almost 69.23%.The High-quality subunits 14+15,7 related with qualityâ‘¢At the Glu-B1 locus, the frequency of subunit 2+12 (80.22%) was higher and that of desirable subunit 5+10 was only 6.59%.â‘£There are 19 HMW-GS types in these winter wheat varieties. The frequency of 1, 7+8, 2+12 is 31.87%,which is the major type. Good subunit composition is lack.4 Effects of HMW-GS on quality traits of Aimengniu and its derivativesWheat quality is affected by many factors, High Molecular Weight Glutenin Subunit (HMW-GS) is one of the most important factors. Subunits on Glu-B1was not the most important to quality of wheat, the contributions of variation in Glu-A1 to the quality traits were determined 2* or Null. Quality effects in Glu-D1 mainly come from 5+10. The varieties (lines) which had 2*subunits in Glu-A1 locus had higher Protein content,sedimentation and longer stablity time than those other subunits.There were three kinds of HMW-GS on Glu-A1,the contributions of variation in Glu-A1 to the quality traits were determined as 2*>1>null. There were five kinds of HMW-GS on Glu-B1, The contributions of variation in Glu-B1 to the protein contents were determined as 7>14+15>7+9>7+8>6, There were four kinds of HMW-GS on Glu-D1 , Their contributions to the protein contents were determined as 5+12>5+10>4+12>2+12.Their contributions to the sedimentation value were 2*>1>N, 14+15>7+9>7+8>7>6, 5+10>5+12>2+12>4+12,Their contributions to dough development time were 1>2*>N, 14+15>7>7+9>7+8>6, 5+10>5+12>2+12>4+12, Their contributions to dough stability time were 2*>1>N, 14+15>7>7+8=7+9>6, 5+10>5+12>2+12>4+12,Combining the protein contents, the sedimentation value , Dough development time and Dough stability time as the evaluation index , the best subunit combinations was 2*/14+15/5+10.Although using different quality traits to detemine the effects of the subunits , 2* and 1 were better than Null, 5+10 was the best on Glu-D1 generally. 5 Genetic diversity of Aimengniu and its derivatives on SSR MarkersGenetic diversity in 91 accessions of Aimengniu and its derivatives was assessed using SSR markers. The 20 pairs of SSR informative primers generated a total of 120 alleles. Each pair of SSR primer could detect 3 to 9 alleles with an average of 6.0. Genetic similarities among 91 accessions ranged from 0.411 to 0.961,which indicated that genetic difference among them was significant. Aimengniu and its derivatives could be clustered into four groups with UPGMA cluster analysis. It could be a suitable index for genetic divergences among wheat cultivars. The genetic diversities of Aimeng niu ,s derivatives have the tendency of increasing with time slightly, This is related with using Aimengniu and its derivatives repeatly of breeding units. A set of derived lines have been developed from crosses between Aimengniu and Shannong Fu 66, Shannong Fu 63,selecting parents of hybrid reasonably is significant.
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