Karyological and cytogenetical studies on conifer plants in extreme conditions
a:2:{s:4:"TEXT";s:68:"E. N. MURATOVA, T. S. SEDEL’NIKOVA, O. V. GORYACHKINA, A. V. PIMENOV";s:4:"TYPE";s:4:"text";}
a:2:{s:4:"TEXT";s:122:"V. N. Sukachev Institute of Forest SB RAS Federal Research Center “Krasnoyarsk Science Center SB RAS”, Krasnoyarsk, Russia";s:4:"TYPE";s:4:"text";}
Keywords: Pinaceae, Cupressaceae, chromosome number, karyotype, chromosome and genome mutations, nucleolar regions, fluorescent hybridization in situ, extreme conditions
Abstract
Results of karyological and cytogenetical studies in populations of conifer species of Pinaceae and Cupressaceae families from extreme conditions are summarized. In conifers growing in southern and northern borders of areas, on ecological limits of distribution, in anthropogenically disturbed ecosystems, at the introduction, chromosome variability is revealed. A high frequency of changes in the number of chromosomes (mixoploidy, aneuploidy and polyploidy) and their morphology were noted. Different types of chromosome anomalies (ring and polycentric chromosomes, fragments, multiple chromosome irregularities), B-chromosomes occurrence, irregularities of mitosis and meiosis are found. Using classical methods and fluorescent in situ hybridization (FISH), studies of the polymorphism of the nucleolar regions of chromosomes were carried out, and features of the loci of the 5S and 45S ribosomal RNA genes were revealed.
|
