Moleculer Identification Of Hardness-related Genes And Analysis Of Yield And Quality Parameters Associated With Grain Hardness Genes

Grain hardness is one of the important traits in wheat quality,according to thegrain hardness,common wheat was divided into three types in world,soft wheat,hardwheat and medium hybrid whrat.The hard wheat has the characteristics of highhardness,high protein content,high gluten strength,coarser flour particles,bibulous ratelow and is suitable for baking bread,etc.The soft wheat with soft endospermtexture,low protein content and weak gluten strength is suitable for producing allkinds of pastries.The medium hybrid wheat with moderate hardness and mediumgluten strength is suitable for making class food which need shorter fermentationtime.In order to adapat to the present situation that the demand for high quality wheatis continue growing in our contry,this paper studied the haraness genes so as to findhigh-quality genotype and provide effective information for quality improvement.This experiment chosses45new wheat varieties of huanghuai area which were inthe regional test experiment and167huanghuai history and mean varieties.Throughfield investigation and indoor quality experiments,we get the field and qualitytraits.By sequencing the products of primer amplification specificity,enzyme andgelectrophoresis appraisal methods to identify genotype.At the same time,thisexperiment also selected the64hexaploid triticale to study the distubution of hardnessgene in triticale and the relationship between hardness gene and the genotype.Mainconclusions are as follows:1In167huanghuai history and mean vatities, Puroindoline b-2（Pinb-2）hasmany allelic variation types, pinb-2v4was in group A while pinb-2v1was in group D,four allelic variation types including Pinb-B2v2,Pinb-B2v3a,Pinb-B2v3b and Pinb-B2v3c was in group B.Acroding to analyze the relationship between differentvariation types and yield traits,we found that Pinb-2v3b genotype possessed thehighest1000-grain weight, grain diameter, grain number per spike, grain weight perspike, and grain weight per plant. Therefore, Pinb-2v3b genotype possibly has morepreferable yield-related traits than other three genotypes. Additionally, Pinb-2v3agenotype possessed the highest flag leaf width, length, and area. Genetic mappingindicated that Pinb-2was located on the long arm of chromosome7B close to SSRmarker Barc315.2In45new wheat varieties which were in the regional test experiment, At thePinb-B2locus,there are also four alleles including Pinb-B2v2,Pinb-B2v3a,Pinb-B2v3band Pinb-B2v3c in group B.Analysis of the relationship between different variationtypes and grain traits indicated that Pinb-2v3b genotype had the highest SKCShardness and Pinb-2v3c genotype had the lowest hardness in soft wheat. However,there was no significant difference on1000-kernel weight and grain diameter betweenwheat cultivars with different Pinb-B2alleles. Analysis of Pinb-B2alleles withmixolab parameters indicated that the C4and C5values of Pinb-2v2genotype weresignificantly lower than Pinb-B2v3a,Pinb-B2v3b and Pinb-B2v3c genotypes.3There are3common wheat materials in64triticale,and in the rest triticalematerials we found many allelic variation types of sina and sinb.In this research wefound3new alleles for sina while2new alleles for sinb,according to the rules ofnaming,they are named sina-R1b,sina-R1c,sina-R1d and sinb-R1e,sinb-R1f.Thehomology of the nucleotide level between sinb-R1e,sinb-R1f and sinb-R1is98.9%,and the similarity in amino acid level is98.8%.sinb-R1e and sinb-R1f are highlysimilar to hardness gene of oats in the nucleotide level,which is accord with the studyof Li Genying and Simeone.There are9genotype combinations in triticale of thisexperiment, sina-R1b/sinb-R1c and sina-R1c/sinb-R1d are the2main genotypecombinations. Analysis of the SKCS hardness of different genotype combinations oftriticale materials indicated that hardness range between different materials of thesame genotype combination is bigger,therefore genotypes of sina and sinb is may notthe key fators to decide the hardness of grain in triticale materials,there are other fators which has a great influence on the hardness of triticale.