Marking method for resistance gene homologues based on EST(Expressed Sequence Tag) data mining

Abstract

The invention discloses a marking method for resistance gene homologues based on EST data mining. The method comprises the following steps: (1) sequence mining and primer designing; (2) RGA sequence mining and primer designing, wherein 96 R protein sequences of different species are collected through literature, 196 R protein sequences of Arabidopis thaliana are downloaded at the same time, and EST data of three cotton species are downloaded from TIGR; and (3) genetic mapping of developed markers, wherein a BC1 population between Gossypium hirsutum and G. barbadense is used, then polymorphism is screened by using the parent of Hubei cotton-22 and 3-79 under the condition of electrophoresis of single-strand conformation polymorphism, screened polymorphism markers are used for polymorphism analysis of the BC1 population, and obtained data are introduced into JoinMap3.0 for construction. The method provided in the invention has the advantages of low cost, no need for cost for amplification of degenerate primers and considerable monoclonal sequencing, a greater number of obtained sequences, more abundant sequence varieties and capacity of providing effective molecular markers for molecular breeding.

Description

technical field [0001] The invention belongs to the technical field of cotton disease-resistant breeding, and more specifically relates to a method for marking resistance genes homologues (RGHs) based on EST data mining. Breeding for disease resistance shortens breeding time and reduces costs. Background technique [0002] During the growth of crops, they will be harmed by various diseases and insect pests, resulting in a decline in yield or quality. Cultivating disease-resistant varieties through molecular breeding plays an important role in reducing disease damage, ensuring high yield and high quality, and reducing the use of pesticides. [0003] Except for a few crops whose genomes have been sequenced, such as rice and corn, most crops have a weak research foundation or some natural weaknesses. Some crops have large genomes with many repetitive sequences, or low polymorphism ratios, making it difficult to construct high-density genetic linkage maps, making it difficult ...

AI Technical Summary

Problems solved by technology

For example, many degenerate primers are designed based on the P-loop, Kinase2, Kinase3a, and GLPLAL of the NBS region of the R gene, and the amplification product can only include the NBS region, and it is not difficult to obtain NBS flanking sequences.

It is also difficult to obtain homologous sequences for some genes that are not suitable for designing degenerate primers

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