Ansari Helal Ahmad, Ellison Nicholas, Stewart Alan Vincent, Williams Warren Mervyn
AgResearch Ltd, Grasslands Research Centre, Palmerston North 4412, New Zealand Grasslands Research Centre Palmerston North New Zealand.
PGG Wrightson Seeds, Kimihia Research Centre, 1375 Springs Road, RD4, Lincoln 7674, New Zealand Kimihia Research Centre Lincoln New Zealand.
Comp Cytogenet. 2022 Mar 24;16(1):39-54. doi: 10.3897/compcytogen.v16.i1.79056. eCollection 2022.
The - complex of the subtribe Loliinae (Poaceae) includes several economically important forage and turf grasses. This complex encompasses Linnaeus, 1753, Festuca Linnaeus, 1753 subgenus Schedonorus (P. Beauvois, 1824) Petermann, 1849 and Romero Zarco et Cabezudo, 1983. New FISH results of 5S and 18S-26S rDNA sequences are presented for three species and the results are interpreted in a review of distribution patterns of 5S and 18S-26S rDNA sequences among other species in the complex. Romero Zarco et Cabezudo, 1983 (2 = 2 = 14) displayed a distribution pattern of rDNA sequences identical to that of Hudson, 1762, supporting a close phylogenetic relationship at the bottom of the phylogenetic tree. "" Lamarck, 1779 accessions sourced from Morocco showed a different pattern from European and could be a unique and previously uncharacterised taxon. North African Hochstetter ex A. Richard, 1851 had a marker pattern consistent with allotetraploidy and uniparental loss of one 18S-26S rDNA locus. This allotetraploid has previously been suggested to have originated from a hybrid with (Festucaarundinaceavar.glaucescens Boissier, 1844). However, the distribution patterns of the two rDNA sequences in this allotetraploid do not align with , suggesting that its origin from this species is unlikely. Furthermore, comparisons with other higher alloploids in the complex indicate that was a potential donor of two sub-genomes of allohexaploid (Linnaeus) Villars, 1787. In the overall complex, the proximal locations of both rDNA markers were conserved among the diploid species. Two types of synteny of the two markers could, to a considerable extent, distinguish allo- and autogamous species. The ancestral parentage of the three allotetraploids has not yet been determined, but all three appear to have been sub-genome donors to the higher allopolypoids of sub-genus . Terminal locations of both the markers were absent from the diploids but were very frequently observed in the polyploids.
黑麦草亚族（禾本科）的复合体包含几种具有重要经济价值的饲料和草坪草。这个复合体包括1753年的林奈草属、1753年的羊茅属Schedonorus亚属（P. Beauvois，1824年）、Petermann，1849年以及Romero Zarco和Cabezudo，1983年的相关分类。本文展示了三个物种5S和18S - 26S rDNA序列的新荧光原位杂交（FISH）结果，并在对该复合体中其他物种5S和18S - 26S rDNA序列分布模式的综述中对结果进行了解释。Romero Zarco和Cabezudo，1983年（2n = 2x = 14）显示出与1762年的哈德逊草相同的rDNA序列分布模式，支持了系统发育树底部的密切系统发育关系。1779年拉马克描述的来自摩洛哥的种质显示出与欧洲种质不同的模式，可能是一个独特的、以前未被描述的分类单元。北非的1851年由A. Richard依据Hochstetter标本描述的物种具有与异源四倍体和一个单亲本18S - 26S rDNA位点缺失一致的标记模式。此前有人认为这个异源四倍体起源于与（1844年Boissier描述的Festucaarundinaceavar.glaucescens）的杂交种。然而，该异源四倍体中两个rDNA序列的分布模式与该物种不一致，表明其不太可能起源于该物种。此外，与该复合体中其他更高倍性的异源多倍体比较表明，它是1787年Villars描述的异源六倍体（林奈草）两个亚基因组的潜在供体。在整个复合体中，两个rDNA标记的近端位置在二倍体物种中是保守的。这两个标记的两种类型的同线性在很大程度上可以区分异交和自交物种。这三个异源四倍体的祖先亲本尚未确定，但这三个似乎都是Schedonorus亚属更高倍性异源多倍体的亚基因组供体。这两个标记的末端位置在二倍体中不存在，但在多倍体中经常观察到。
