|
|
|
Protasov, A.A., 1997. The Phenotype Diversity of Some Zebra Mussel (Dreissena polymorpha Pallas) Populations from the Ukraine, Byelorussia, and Poland, National Academy of Sciences of Ukraine Abstract from The Seventh International Zebra Mussel and Other Aquatic Nuisance Species
Conference, New Orleans, Louisiana, January 1997
The populations of organisms can be defined by some types of their structure — age, sex, body-size and others. But one of the most interesting and informative is phenotype structure. The phenotype is composition of separate alternative signs (morphological, for example), marking the genetic peculiarities of different groups of individuals in populations. The most significant property of phenes is their adaptability, i.e. enormous number of theoretically possible phenotypes (compositions of phenes) are presented in real natural conditions with limited number of adapted forms. The diversity of morphological signs of zebra mussels is known very well, but now the convenient system of description of morphological signs is absent. We are suggesting a new original symbol system for the coding of Zebra mussels shells phenotype with 19 signs, including signs of pattern, sculpture and metric indices. The elementary signs, phenes of pattern are zigzag, arched,wavy and radial lines, spotted, pattern of "chevron" -type and ray-type. The signs of sculpture are roughness of shell surface connected with growth zones and other sculpture. The degree of colour intensity was estimated too. The shells of "zero-pattern"- type was only light or dark. As far as one shell could have many signs all phenotype could be described by phene-formula in letter symbols. In rivers Pripiat, Dnieper, Sasyk lake (Ukraine), Konin lakes system (Poland) it was marked more than 80 phenotypes of Zebra mussels. The increase of melanist specimen portion from river Prypiat to low Dnieper was noticed. Together with this phenomenon the decrease of intrapopulation diversity was observed: 6.32 + 0.21 and 3.06 + 0.23 (calculated by Zthyvotovski, 1982). Phenotype diversity (by Shannon) was higher in Sasyk lake — 4.54 bit/phenotype, in Konin lakes it was 2.9-3.7 bit/phenotype, and phenotype diversity was decreased from river Prypiat to low Dnieper: 4.3-2.7 bit/phenotype as well as intrapopulation diversity. The similarity of phenotype of zebra mussels from river Prypiat (basin of Dnieper), Konin lakes (basin of Oder river) and Sasyk lake (basin of Danube) was noticed. Phenotype structure of population from Kachovskoje reservoir was not similar to other investigated water bodies. Contact: A.A. Protasov, Institute of Hydrobiology, National Academy of Sciences of
Ukraine, 12, Prosp. Garoyev Stalingrada, Kiev-210 254655, MSP, Ukraine |