Мазманян M.А., Карагян Г.А., Степанян И.Э., Нестерова О.Л.
Кариологический анализ некоторых партеногенетических популяций Bromius obscurus (Linnaeus, 1758) (Coleoptera, Chrysomelidae)
It is known that leaf beetle Bromiusobscurus L. from geographically isolated populations has the races with different reproduction mode and ploidy. Parthenogenetic females of some European populations have triploid chromosome number (3n=24), while bisexual populations from North America are diploid (2n=16, Xyp) (Suomalainen, 1965). Thus, we considered that it would be interesting to study and compare the karyotypes of additional populations of B. obscurus in order to elucidate the karyological polymorphism of this species.
B. obscurus specimens from three geographically isolated populations from Armenia (“Kajaran”, “Spandaryan”, “Margahovit”), one population from Russia (“Moscow”) and one Byelorussian population (“Minsk”) were collected on Chamerion angustifolium L.
All specimens studied were triploid parthenogenetic, with chromosome number 3n=24 (n=8). The chromosome set is similar in all populations studied with minor differences in size of some chromosomes. But, in “Minsk” population, the one chromosome of the large metacentric triplets displayed secondary chromosomal strangulation on the one of arms. Besides, the triplet of acrocentric chromosomes was consist of chromosomes of nearly equal size in “Moscow”, “Minsk” and “Margahovit” populations, while one of these acrocentrics was quite longer than the others in specimens from “Kajaran” and “Spandaryan” populations. Additionally, between the karyotypes of the studied populations were found some differences in the number of chromosomes with visible pericentromeric heterochromatic blocks.