Poa sect. Poa subsect. Nivicolae (Prob.) Tzvelev was circumscribed to include four species of the Soviet Union: Poa shumushuensis, Poa caucasica, Poa irkutica, and Poa veresczaginii. Bayesian phylogenetic analyses of plastid and nuclear‐ribosomal DNA revealed that it is polyphyletic, none of these species are closely related. Poa shumushuensis, type of sect. Nivicolae, or its ancestor, likely displayed the nrDNA genotype characteristic of the higher polyploid P. sect. Malacanthae. Genotype codes are designated for each species: Hx, C c, Php, and Shp. Poa sect. Nivicolae s.s. is restricted to P. shumushuensis; P. sect. Irkuticae is restricted to P. irkutica; P. caucasica is moved to P. subg. & sect. Caucasicae nov.; and P. sect. Dschungaricae is resurrected for P. veresczaginii and two other species. Although diclinous breeding systems are known in many western hemisphere species of Poa, dicliny is infrequent and little studied in Asian Poa. Poa shumushuensis is judged to be either sequentially gynomonoecious or gynodioecious. A ratio of 2 perfect‐, to 2 mixed‐, to 1 pistillate‐flowered inflorescences from different plants in P. shumushuensis is suggestive of a recessive allele for stamen suppression, and this is associated with subtle sexual‐dimorphism. Poa irkutica is diclinous with a breeding system between simple gynomonoecy and sequential gynomonoecy; P. caucasica is perfectly flowered; and P. veresczaginii has infrequent abortive anthers, indicative of limited dicliny, or sterility for other reasons possibly related to its reticulate origin. In total, 23 Asian species are here reported to be diclinous and their breeding systems are characterized. A lectotype is designated for P. fauriei.

中文翻译：

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早熟禾中的育种系统和系统发育，特别关注东北亚：早熟禾树 Ohwi 和 sect. 的问题。Nivicolae（禾本科）

Poa 教派。Poa 小节。Nivicolae (Prob.) Tzvelev 被限定为包括四种苏联物种：Poa shumushuensis、Poa caucasica、Poa irkutica 和 Poa veresczaginii。对质体和核-核糖体 DNA 的贝叶斯系统发育分析表明它是多系的，这些物种都没有密切关系。Poa shumushuensis，宗派类型。Nivicolae 或其祖先可能显示出较高多倍体 P. sect 的 nrDNA 基因型特征。马尾藻。为每个物种指定基因型代码：Hx、C c、Php 和 Shp。Poa 教派。Nivicolae ss 仅限于 P. shumushuensis；P. 教派。Irkuticae 仅限于 P. irkutica；P. caucasica 移至 P. subg。＆节。高加索十一月；和体育教派。Dschungaricae 因 P. veresczaginii 和其他两个物种而复活。尽管在许多西半球的早熟禾品种中已知二棱繁殖系统，但在亚洲早熟禾中二棱繁殖并不常见且很少被研究。Poa shumushuensis 被判断为顺序雌雄同株或雌雄异株。来自 P. shumushuensis 不同植物的 2 个完美花序、2 个混合花序和 1 个雌蕊花花序的比率表明存在抑制雄蕊的隐性等位基因，这与微妙的两性异形有关。Poa irkutica 在简单雌雄同体和连续雌雄同体之间具有繁殖系统；P. caucasica 完全开花；和 P. veresczaginii 具有罕见的败育花药，表明有限的二期，或由于其他可能与其网状起源有关的原因而导致不育。总共，据报道，这里有 23 种亚洲物种是二异性的，它们的繁殖系统也有特征。为 P. fauriei 指定了选型。