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Mixed Inheritance and QTL Location Study on Earliness and Its Related Traits of Short Season Cotton

Author: DongNa
Tutor: WangQingLian
School: Henan Institute of Science and Technology
Course: Crop Genetics and Breeding
Keywords: Short-season cotton The precocious and related traits Hybrid Genetic The main gene - multiple genes QTL mapping
CLC: S562
Type: Master's thesis
Year: 2010
Downloads: 19
Quote: 1
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Abstract

Our people will be less, the main cotton-producing areas and grain producing areas, the breeding and promotion of short-season cotton varieties, ease the grain and cotton contention to contradiction, an effective way of grain and cotton double harvest. Therefore, to study the short-season cotton the precocious and related traits genetic find molecular markers linked closely associated with genes important for the short-season cotton breeding. In this study, the major gene - polygenes mixed inheritance model and analysis method of short-season cotton the precocious and related traits, genetic analysis, application of the composite interval mapping method to detect and locate short-season cotton precocious and related traits QTL. A short-season cotton the precocious and related traits mixed genetic building one hundred cotton 2 × TM-1 combination of P ₁ P ₂, of F _{1 < / sub> B ₁, _{B 2} F ₂ 6 generations groups, respectively, in China's Yellow River cotton (environment I) and two different ecological environment of the the northwestward cotton (Environmental II), the major gene - polygenic mixed genetic models and analysis methods to carry out a genetic analysis of the short-season cotton precocious and related traits. The results are as follows: 1. Addition to environmental Ⅱ blooming period clothes exceptionally, other traits were detected in two environments to the main gene, indicating that the universality of the short-season cotton precocious and related traits master gene. 2. Optimal genetic model of growth period in the two environments are the same major gene with polygenic component trends fruiting branches beginning section and boll weight optimal genetic model, its mode of inheritance in different environments are relatively stable; major gene with polygenic component trends contrary, its genetic law has yet to be further explored; seedling stage, bud stage, the blooming period and lint genetic model component of a major gene with polygenic heritability varied, indicating different environment there is a big impact on the gene expression of these traits, their choice only in the specific environment in order to improve breeding efficiency. Estimate the short-season cotton precocious and related traits segregating major gene polygenic inheritance rate determined trait selection of the most efficient generations; comparative analysis of the two environments for each trait heritability found that the growth period, the seedling stage, bud stage, high and low the fruiting branches beginning section height and fruiting branches beginning Festival heritability trend is relatively stable growth period as an important symbol of the cotton precocious traits traits, genetic rate highest total in the two environments in different ecological environment early generation select effective fruiting branches beginning of the section height and fruiting branches beginning section can be used as identification reliable form of earliness indicators. The mode of inheritance of each trait in the two environments is different. Growth period, the bud stage and fruiting branches beginning section height in the two environments are the main genetic-based; seedling stage, the blooming period, fruiting branches beginning section and lint major gene-based environmental Ⅰ, Ⅱ in the environment the polygenic inheritance main; bell polygenic inheritance mainly focuses on the environment Ⅰ major gene-based environmental Ⅱ. Traits can be used for major gene-based single cross restructuring or simple backcrossing polymerization backcross or recurrent selection cumulative favorable allele method can be used to improve breeding efficiency based on multiple genetic traits. , Short-season cotton the precocious and related traits QTL position to build one hundred cotton 2 × TM-1 combination F2 mapping population, the use of the SSR and Joinmap 3.0 software to build a genetic linkage map using WinQTLCart2.5 composite interval for Figure 8 precocious and related traits in the F2 population QTL mapping. The results are as follows: 1. Constructed a 152 SSR markers, 40 linkage groups, with a total length 1010.3cM, covering 22.6% of the cotton genome, the average distance between markers genetic linkage map for 5.91cM short-season cotton molecular markers. The map is a short-season cotton continental hybridization marker density biggest first genetic linkage map. 40 linkage groups have been targeted to the 21 chromosomes, has laid a good foundation for further saturated molecular genetic linkage map for the short-season cotton. Detected 22 QTL to control precocious and related traits, including four growth period QTL seedling stage of QTL bud stage QTL, flowering and boll period of the QTL fruiting branches starting section height of QTL 1 a fruit branch beginning Festival QTL, a bell weight QTL and the QTL 4 lint percentage explained 1% -16% of the phenotypic variation, respectively, 8% -44%, 5% -46% 1% -10%, 10% , 6% and 6% -7% and 5% -24%. Molecular markers detected a major QTL main gene - multi-gene analysis results have been very good complementary authentication. Different traits QTL on chromosome regions clustered distribution shows that may be present in the cotton genome gene-rich region of highly repetitive, the precocious traits associated genes may be tightly linked or pleiotropic effects, from the molecular level to explain them the between genetic relationship. Control the precocious and related traits QTL allele from one hundred cotton, its genetic effects are dominant effects. Major QTL detected in this study can be used for short-season cotton marker-assisted selection breeding.}

Mixed Inheritance and QTL Location Study on Earliness and Its Related Traits of Short Season Cotton

Abstract

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