Studies Of The Molecular Markers And Growth Characteristics Of The Multiple Pengze Crucian Carp

In the breeding practice, it was found that there was differentiation of appearance among the offspring of pengze crucian carp eggs stimulated by sea carp sperm. Some of the offspring are similar to the female parent in shape, but at the same time some partly have some features like the male parent. The length of their mouth, the number of their squama and the hunch of their back are like their male parent sea carp but different from pengze crucian carp. And the color of pectoral fin and pelvic fin is just between that of female parents and male parents. It suggests a fusion of the genome of male parents and that of female parents. These with male parent's character were called multiple pengze crucian carp.A research was did in the analysis of the content of DNA of multiple pengze crucian carp by flow cytometry and found that there were two different types. The DNA content in one type accorded tetraploid, but that in another type was just between triploid and tetraploid called aneuploid. In order to distinguish the tetraploid faster from the aneuploid, 5 tetraploid and 5 aneuploid with the result of the analysis of the DNA content have been chosen, and Random Amplified Polymorphic DNA(RAPD) amplification has been done with their DNA. After optimizing the system and situation of the reaction, 8 random primers which can amplify specially in the tetraploid but not in the aneuploid have been found out from 56 RAPD random primers. But the localization of RAPD itself that it can hardly be repeated restricts the use of the random primers. In order to find out a molecule marker which can sort out the tetraploid easier, faster, more efficiently and more steadily, the special DNA bands that was amplified by the random primers was reclaimed, cloned and measured the sequence, and a pair of primers with 24bp according to the sequence was designed, and then using this special primer to amplify the special DNA sequence in the tetraploid, known as Sequenced Characterized Amplified Regions (SCAR) . After research, 4 SCAR markers have been successfully established which can distinguish tetraploid from aneuploid effectively. By measuring the growth of offspring of multiple pengze crucian carp produced by different type of "crossbreed" and the growth of pengze crucian carp, and calculating the average weight and special growth rate (SGR)of them in different stages, it is proved that pengze crucian carp grows faster than pengze crucian carp. And by designing different "crossbreed"groups, it is found that the offspring acquired using the sperm of sea carp as a heterogenous sperm have more advantage in growth than using other sperm, and the growth advantage of multiple pengze crucian carp can be inherited steadily.