| As a kind of high quality fish, aquatic science research institute in Jiangxi Province and aquatic science research institute in Jiujiang have bred Carassius auturas var pengze. It has been cultivated in nation-wide. There were some reports about its ways of reproduction and heredity, but these results are no in agreement with each other.Several important biological characteristics such as fertilization cytology and hereditary property of Carassius auturas varpengzehad been analyzed in this paper. The results are summarized as follows:1. Cytogenesis of chromosome number and ploidy of carassius auturas var pengzeChromosomes preparation of Carassius auratus var pengze was made from kidney cells in vivo. Statistics analysis of chromosome number of carassius auturas var pengze show the metaphases of which chromosome number is over 150 have some small chromosomes.Analysis of karyotype shows that the 150 basic chromosomes can be divided into four sections according to the position of centromere. The number of homologous chromosome groups in each section is as much as the number of homologous chromosome pairs in diploid species of the Carassius auratus. Each homologous chromosome group has three homologous chromosomes.In subtelocentric chromosome section, all of the three chromosomes of the third homologous chromosome group have satellites at their short arms. Obviously, these three satellite homologous chromosomes can be regarded ascytogenetic characteristic of triploid.DNA relative content of muscle cells of Carassius auratus var pengze and Carassius auratus Far red were measured through flow cytometer. DNA relative content of muscle cells of Carassius auratus var pengze revealed that the ratio of DNA relative content of Carassius auratus var pengze and that of diploid Carassius auratus varred is 1. 55 : 1. It is consistent with the analysis result of chromosome. In those metaphases which the chromosome number is over 150, there is unstable number of little chromosomes that can not be classified into the four sections. Therefore, these little chromosomes can be considered supernumerary chromosomes.These results suggest that carassius auratus var pengze is a triploid Carassius auratus. Chromosome number is 3n=150+. Statistical analysis of chromosome number of kidney cell shows that chromosome set of Carassius auratus var pengze consists of 150 basic chromosomes and 0 to several little supernumerary chromosomes. Karyo formula is 3n=33m+51sm+33st+33t.2. gynogenetic Cytology of carassius auratus var pengzeWith the method of histological section, it was observed that fertilization cytology of Carassius auratus var pengze(♀) × Carassius auratus var pengze ( ♂) . After inseminated, it was observed that a sperm entered egg through micropyle and a polarbody was extruded. But after a sperm entered the egg, spermatozoon nucleus beside female pronucleus was condensed and cannot fuse with female pronucleus. The result shows that Carassius auratus var pengze is gynogenetic reproductive modes. There were no pairs of homologous chromosome in meiosisI metaphase of spermatocyte of Carassius auratus var pengze. It shows the unusual meiosis I during spermatogenesis. Theratio of DNA relative content of tail fin cell and sperm of Carassius auratus var pengze is 2. 218:1, it reveals that DNA relative content of sperm is half of somatic cell. During spermatogenesis, meiosis I is abnormal, this section preliminarily analyzed the mode of the stability of chromosome ploidy of Carassius auratus var pengze and the different mechanism of ogenesis and spermatogenesis in order to better understand the reproductive modes and formation mechanism of triploid of Carassius auratus var pengze.3. Isozyme comparison of carassius auratus var pengze and carassius auturas var redWith the method of vertical polyacrylamide gradient gel electrophoresis (PAGE), to comparison study the lactate dehydrogenase (LDH), malate dehydrogenase (MDH) and esterase (EST) in muscle, kidney, liver and tail fins of gynogenetic c...
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