Karyotype analysis and genome relationships of 22 diploid species in the tribe Triticeae

Abstract

Karyotypes were analyzed on 24 diploid taxa (mostly perennials) belonging to eight Triticeae genera, which are defined by genome content (basic set of seven chromosomes): (i) Agropyron (P genome), (ii) Thinopyrum (J genome), (iii) Secale (R genome), (iv) Hordeum (i genome), (v) Pseudoroegneria (S genome), (vi) Psathyrostachys (N genome), (vii) Australopyrum (W genome), and (viii) Critesion (H genome). In addition to traditional karyotype preparations, the metaphase root-tip chromosomes were analyzed by an interactive microcomputer program that printed an idiogram in which chromosomes were arranged by length. Genomes, arranged by decreasing length, are R, I, P, N, J, S, H, and W (with lengths ranging from 61.29 to 39.39 μm). Almost without exception, karyotypes of species within a genus manifest a pattern that is unique to the genome. Morphologically unique genomes are useful diagnostic features in genome identification and can complement interpretation of chromosome pairing in genome analysis.Key words: Triticeae, diploid, karyotype, genome relationship.

.BETA.-amylase Variation in Wild Barley Accessions

“…Several reports have provided evidence supporting his hypothesis (Bothmer et al 1983, 1986, Doebley et al 1992, Jørgensen 1986, Kataoka et al 1987, Linde-Laursen et al 1990, 1992a, Pelger and Bothmer 1992. However, there are also reports that these two species were significantly different or not very closely related (Hsiao et al 1986, Shcherban and Vershinin 1992, Xu et al 1990. Molnar et al (1989) suggested that the ribosomal DNA of H. bulbosum was more closely related to that of the H. murinum complex than to H. vulgare.…”

Meiotic associations at metaphase I in diploid, triploid, and tetraploid Russian wildrye (Psathyrostachys juncea (Fisch.) Nevski.

“…It appeared that chromosome length was not responsible for the variations in trivalent frequency. Both the N and R genomes have similar, long chromosomes (Hsiao et al 1986), and the short chromosomes of the S and H genomes formed 2.74 to 4.96 trivalents in their autotriploids (Wang 1990). The R-genome chromosomes could also form up to four chiasmata per bivalent, but the mean chiasmata per bivalent was 2.00 (Galindo and Jouve 1989).…”

Genetic diversity and relationships among accessions of five crested wheatgrass species (Poaceae: Agropyron) based on gliadin analysis

“…Mellish et al (2002) also reported that the majority of the AFLP variance (88%) was found within the Agropyron species population, which may be because they are all outcrossing species. Hsiao et al (1986) described that although A. mongolicum and A. cristatum had similar genome lengths, there were some structural rearrangements between their P genomes, which were called the P c and P m genome. Similarly, A. mongolicum was not closely related to A. cristatum and other species in the study.…”