Studies On The Cytogenetics Of Bufo Raddei Strauch In Lanzhou Section Of The Yellow River

The studay measured and compared with the results of the investigation on the Karyotypes, the Ag-NORs, the micronucleus frequency, the sister chromatid exchange(SCE) of Bufo raddei strauch in Lanzhou section of the Yellow River(Liujiaxia region, Gaolan region, Lanzhou region). The results showed that:Bufo raddei strauch in Lanzhou section of the Yellow River had a diploid chromosome number of 22 and its karyotype fomular is 20m+2sm, NF=44.The chromosomes of Bufo raddei strauch were characterized by six pairs of macrochromosomes and five pairs of microchromosomes. All of them were metacentric and submetacentric, accorrding to the size and position of the centromeres, they can be arranged in 4 groups. In these groups, the No.4 pairs can be identified unequivocally by direct observation for the presence of satellites on the arms. In this experiment we found there is no visible evidence of sex chromosome dimorphism.The main Ag-NORs were located in the short arms of the No.4 chromosomes, and also were located in the long arms of the No.4 chromosomes.By the method of tadpole micronuclei assay, the results of water quality inducing red blood corpuscles micronuclear and abnormal core from three resources, water of Yellow river in Lanzhou , water of Yellow river in Liujiaxia, water of Yellow river in Gaolan, were compared. The aired drink water as blank assay, results shows that tadpole red blood corpuscles nuclear cell rate and core unusual cell rate from lanzhou group show higher rate than contrasted group (P<0.05) after one week. Especially for tadpole red blood corpuscles nuclear cell rate of the Lanzhou group, it is marginally higher than the other two groups water (P<0.05). Tadpole red blood corpuscles nuclear cell rate and core unusual cell rate in Gaolan group(100% concentration, 50% concentration) not statically higher than that of the contrasted group(P>0.05).The micronucleous rates of the red blood corpuscles of Bufo raddei strauch from three groups, Lanzhou group, Gaolan group and Liujiaxia group, were compared. The results is as follows: The red blood corpuscles nuclear cell rate between the Lanzhou group and Liujiaxia group was statistically difference (P<0.05), and between the Lanzhou group and Gaolan group was statistically difference (P<0.05).The sister chromatid exchange(SCE) of the marrow cell of Bufo raddei strauch from three groups, Lanzhou group, Gaolan group, Liujiaxia group, were compared. There was statistically difference (P<0.05)between the Lanzhou group and Liujiaxia group, we also found that the SCE frequency of marrow cells in Bufo raddei was relatively high, which was higher than that of mammals in general.In the present study, we preliminarily discussed the chromosome diversity of Bufo raddei strauch in the Lanzhou section of the Yellow River and the relation between the water pollution and Bufo raddei strauch, provideing a theoretical basis about that to further study on Amphibians in Lanzhou section of the Yellow River in future.