A method for creating new strains of yellow catfish by backcross breeding

Abstract

The invention discloses a method for creating a new strain of yellow catfish by backcross breeding, which comprises the following steps: (1) taking the yellow catfish as the female parent and the yellow catfish as the male parent, and obtaining the hybrid yellow catfish through interspecific hybridization Catfish F 1 generation; (2) F 1 Breeding and cultivating, and screening to obtain fertile diploid F 1 generation male individuals; (3) with fertile diploid F 1 The generation male individual is the male parent, and the yellow catfish is the female parent, and the backcross offspring of the hybrid yellow catfish is obtained, that is, the backcross yellow catfish, which is the new strain of the yellow catfish; (4) using the microsatellite marker method and Morphological discriminant function method for identification of backcrossed yellow catfish and hybrid yellow catfish. The growth rate of the backcross yellow catfish obtained by the method is equivalent to that of the male parent hybrid yellow catfish, more than 20% faster than the female parent yellow catfish, and stronger than the male hybrid yellow catfish in terms of low oxygen tolerance. It can quickly and accurately identify hybrid yellow catfish and backcross yellow catfish. The fish will not die during the operation, and the identified samples can continue to be used for breeding or research.

Description

technical field [0001] The invention relates to a method for creating a new strain of yellow catfish by using backcross breeding, and belongs to the field of genetic breeding of yellow catfish. Background technique [0002] Backcross breeding is one of the important means of hybrid breeding, which aims to recross hybrids with one of the parents, so that the offspring can strengthen some excellent traits of the recurrent parents, reduce the separation of hybrid offspring, and retain a few good traits of the non-recurrent parents , thus creating an excellent recombination type. At present, the backcross breeding is mainly widely used in crop varieties such as peanuts, rice, and potatoes. In aquatic animal strains, it is mainly concentrated in fishes such as tilapia, carp and crucian carp, and bream. And the backcross offspring all showed better genetic improvement effect. [0003] Pelteobagrus is the general term for fish of the genus Pelteobagrus, which belongs to the orde...

AI Technical Summary

Problems solved by technology

The hybrid yellow catfish is a hybrid offspring obtained by crossing the yellow catfish as the female parent and the yellow catfish as the male parent. The hybrid yellow catfish has a strong growth advantage, and its growth rate is faster than that of the unselected yellow catfish. The fish population is 22.42% to 35.64% higher, and it has the advantages of strong disease resistance, the seedlings of the year can be grown into market specifications, the low oxygen resistance is stronger than that of the peltrelative catfish, and the strip shape is good. It has been favored by most farmers. It is recognized that it is a new variety with great potential for development; but most individuals are sterile, the ovaries of female individuals are degenerated, and the testes of male individuals are degenerated, and only a small number of spermatocytes of male individuals can be converted into sperm; Compared with catfish, hybrid yellow catfish still has the defect of poor hypoxia tolerance

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