Open AccessChromosome Pairing Patterns in Interspecific Hovdeum Lechleri × H. Vulgare (Cultivated Barley) Hybrids with 2n = 21–29
Author(s) -
Bothmer Roland,
Salomon Björn,
LindeLaursen Ib
Publication year - 1999
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.1601-5223.1999.00109.x
Subject(s) - chiasma , biology , pairing , meiosis , hybrid , chromosome pairing , hordeum vulgare , hordeum , chromosome , genetics , ploidy , interspecific hybrids , genome , botany , poaceae , gene , superconductivity , physics , quantum mechanics
Individual chromosomes or the whole genome of cultivated barley are often eliminated in interspecific Hordeum lechleri × H. vulgare crossing combinations (rarely one or a few chromosomes of H. lechleri are eliminated). This produces series of plants with chromosome numbers ranging from 2n = 21 (true trihaploids of H. lechleri and rarely aneuploids), through 2n = 22‐27 (aneuploids) to 2n = 28, 29 and 30 (true hybrids and aneuploids). In such material the effect on meiotic pairing was studied for 1. influence of parental genotypes; 2. influence on pairing by chromosome number; and 3. influence on pairing by presence/absence of individual chromosomes identified by C‐banding of root‐tip cells. A total of 126 plants representing combinations of seven varieties of cultivated barley and ten accessions of H. lechleri were investigated. Overall there was a large variation in pairing between plants ranging from 0.12–10.09 chiasmata/cell. True trihaploids of H. lechleri (2n = 21) without barley chromosomes had a “basic pairing” ranging from 0.78–4.58 chiasmata/cell. In aneuploids and euploid hybrids the presence of individual barley chromosomes or the entire complement of barley generally resulted in higher pairing than in trihaploids. This contradicts previous proposals of a depressing effect of the H. vulgare genome in interspecific Hordeum hybrids. Some hybrid combinations showed a large difference in pairing according to parental origin. There seemed to be no clear tendencies of pairing related to different chromosomal numbers. The presence of chromosome 4H of barley had a negative effect on meiotic pairing. The greater part of the recorded pairing is assumed to reflect homoeologous pairing between the three genomes of H. lechleri whereas allosyndetic pairing between H. vulgare and H. lechleri chromosomes is considered low.