Open AccessChromosomal polymorphism in isolated populations of Elymus ( Agropyron ) in the Aegean:
Author(s) -
HENEEN WAHEEB K.
Publication year - 1977
Publication title -
hereditas
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.819
H-Index - 50
eISSN - 1601-5223
pISSN - 0018-0661
DOI - 10.1111/j.1601-5223.1977.tb01231.x
Subject(s) - biology , selfing , meiosis , genetics , karyotype , chromosome , ploidy , elymus , botany , cytogenetics , genome , anaphase , evolutionary biology , population , gene , poaceae , demography , sociology
Elymus rechingeri is a tetraploid (2n = 28) cross‐fertilizer which grows in small isolated populations mainly on the Aegean islands. Chromosome morphology was studied in plants raised from seeds collected in nature and in plants resulting from inter‐ and intrapopulation crosses as well as selfing. Chromosomal polymorphism predominated in the material originating from nature and was observed both between and within populations. This polymorphism was expressed in the variable appearance of the three pairs of satellite chromosomes. The most common constitution of satellite chromosomes was found in Aegean and Egyptian materials and was considered to be the constitution characteristic of the species. Expected combinations of different types of satellite chromosomes were found in the offspring after inter‐ and intrapopulation crosses and after selfing. Some offspring plants also showed structural and numerical chromosome deviations. Fertility was lower in crosses between than within populations indicating genetical differences between populations. The karyotype of E. rechingeri shows great similarities to the karyotypes of E. furctus ssp. boreo‐atlanticus (2n = 28) and E. striatulus (2n = 14). The genome formula J 1 J 1 J 3 J 3 was suggested for E. rechingeri . Meiosis was generally normal but asynapsis and multivalent formation at metaphase I and separation difficulties at anaphase I were also encountered.