| Apple is a agricultural products which have competitive advantage in internationalmarket after china accessed to the WTO.At present, the apple juice product processingin urgent need to develop appropriate for the variety of high acid apples.In order to laid the foundation for development of titratable acid content and provide physical, inherited,molecular evidence for cultivated varieties of suitable high acid apples,The apple hybrid combinations (Fuji×Pinklady) and 128 F1 generation groups were used to analyze the genetic characteristics of mature fruit titratable acid content,fruit shape index,fruit firmness,fruit weight,fruit soluble solid content. On that basis,the linked marker was screened by BSA method and SSR technology and verified by F1 population hybrid. The aim of the study was not only to give theoretical support and reference for molecular marker assisted breeding and early sellection of acid/low-acid trait,but also laid the foundation for further apple positioned and clone acidity gene.The main results were as follows:1. The genetic law was studied of Fuji×Pink Lady on behalf of the 6 F1 hybrid character shaped like a titratable acid content, fruit shape index, fruit firmness, fruit weight, peel color, flesh firmness, soluble solids. The results showed titratable acid content, fruit shape index, fruit firmness, fruit weight, soluble solids were tested positive distribution of the continuous variation. The fruit weight in hybrids were widely separated, the average value of hybrid groups lower than the middle of two parents, have obvious recession. But a small amount of large fruit will appear to provide the conditions for greater fruit of breeding. F1 red skin color with yellow and red showing a simple genetic control and red is dominant. From the genetic variation coefficient of F1, the titratable acidity of 6 shapes showed largest coefficient of variation, 58.49%, indicating larger genetic potential and bigger chance for selection in breeding plants with high acid. From the genetic transfer power perspective, the genetic traits passed 6 power order: flesh firmness> soluble solids> titratable acid> fruit shape index> fruit weight. Transmission power which the maximum firmness, indicating that this trait is genetically more stable, reliable choice. 2.The best reaction response to SSR-PCR are as follows through amplification conditions optimized:The reaction(20μl)system contained:DNA 1.0μL,10×Buffer(50 mmol/L Tris-HCl pH 8.8,16 mmol/L(NH4)2SO4,0.1%Tween20)2.0μL,25 mmol/ L Mg2 +1.9μL,2.5 mmol/ L dNTP 1.6μL,1μL of each primer (50 ng/μL),Taq enzyme(5 U/μL)0.2μL.SSR amplification thermal cycling parameters were:94℃predegeneration 4 min,then 94℃denaturation 55 sec,57.5℃annealing 1 min,72℃extension 90 sec,there were 38 cycles a total,and at last extended 72℃10 min.PCR products with 6% polyacrylamide gel electrophoresis, silver staining. Amplified by the repeated test shows good reproducibility and stability of the system.3. A SSR marker Hi01e10 linked to acid/low-acid trait gene were screened from 80 SSR primer pairs by analyzing the genetic characteristics of 76 F1 generation groups,the genetic distance was 10.014cM.The validity of this SSR maker was verified by F1 population hybrid tests and its genetic characteristics of titratable acid. The acid/low-acid trait gene was governed by a major gene, Hi01e10 can be used in early selection and molecular marker assisted selection.
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