Breeding method of a low-temperature-resistant strain of backcross scallop

Abstract

The invention relates to a selective breeding method for a hybridized-Argopecten irradians backcross low-temperature-resistant scallop line. The method is characterized by comprising the steps: firstly, selecting individuals, which are high in growth speed and high in low-temperature resistance, from a family or population of a first filial generation of Argopecten irradians and Argopecten purpuratus as parent scallops; carrying out back crossing on individuals, with high low-temperature resistance, of the first filial generation and Argopecten irradians ova so as to establish a backcross family or population; and then, carrying out selective breeding on low-temperature resistant breeding core groups for at least three times. According to the method, the first filial generation which is high in growth speed and remarkable in heterosis is adopted as a male parent and then is subjected to back crossing with the Argopecten irradians (a female parent) so as to polymerize a chilling-resistant gene of the Argopecten irradians to a first generation of hybridized-Argopecten irradians backcross, the individuals, with high low-temperature resistance, of the first generation of hybridized-Argopecten irradians backcross are taken as a breeding core group and is subjected to continuous 3 generations of low-temperature resistant breeding, the low-temperature resistance is extended to 0 DEG C, the growth speed is increased by 15% compared with that of the Argopecten irradians, and then, a low-temperature resistant new line which is applicable to wintering of Shandong sea area is obtained. Apparently, the method is simple and convenient in operation and is extensively applied to the selective breeding of hybridized low-temperature resistant scallop lines.

Description

technical field [0001] The invention belongs to the breeding technology of shellfish aquaculture, and in particular relates to a method for cultivating low-temperature-resistant strains of backcrossed scallops from the sea. Background technique [0002] The bay scallop (Argopecten irradians irradians) is native to the Atlantic coast of the United States and was introduced to my country in 1982. Due to its fast growth, short breeding cycle and wide temperature tolerance range (-1-31°C), the scallop has become the main cultured species in northern my country (Zhang Fusui, 2000), and its output once reached more than 800,000 tons in 2005. However, due to its own small commodity size (about 5-6 cm), short life span (about 13 months) (Dall., 1909; Minchin., 2003), and long-term sterility after introduction, resulting in breeding quality degradation, resulting in smaller and smaller commercial shellfish (Zhang Guofan et al., 2003), high mortality rate in the breeding process, for...

AI Technical Summary

Problems solved by technology

However, due to its own small commodity size (about 5-6 cm), short life span (about 13 months) (Dall., 1909; Minchin., 2003), and long-term sterility after introduction, resulting in breeding quality degradation, resulting in smaller and smaller commercial shellfish (Zhang Guofan et al., 2003), high mortality rate in the breeding process, for example, in 2007, the bay scallop mortality rate was as high as about 70%, which has seriously restricted the development of the bay scallop aquaculture industry in our province. develop

In response to this phenomenon, domestic shellfish breeders have improved the germplasm of bay scallops through introduction and rejuvenation, and achieved some results, but failed to fundamentally solve the problem of germplasm degradation.