Sokoloff Dmitry D, Yadav Shrirang R, Chandore Arun N, Remizowa Margarita V
Biological Faculty, M.V. Lomonosov Moscow State University, 119234 Moscow, Russia.
Shivaji University, Vidyanagar, Kolhapur 416 004, MS, India.
Plants (Basel). 2020 Oct 24;9(11):1424. doi: 10.3390/plants9111424.
Eriocaulaceae (Poales) differ from potentially related Xyridaceae in pattern of floral organ arrangement relative to subtending bract (with median sepal adaxial). Some Eriocaulaceae possess reduced and non-trimerous perianth, but developmental data are insufficient. We conducted a SEM investigation of flower development in three species of to understand whether organ number and arrangement are stable in , a species with a highly reduced calyx and reportedly missing corolla. Early flower development is similar in all three species. Male and female flowers are indistinguishable at early stages. Despite earlier reports, both floral types uniformly possess three congenitally united sepals and three petals in . Petals and inner stamens develop from common primordia. We assume that scanning electron microscopy should be used in taxonomic accounts of to assess organ number and arrangement. Two types of corolla reduction are found in Eriocaulaceae: suppression and complete loss of petals. Common petal-stamen primordia in do not co-occur with delayed receptacle expansion as in other monocots but are associated with retarded petal growth. The 'reverse' flower orientation of is probably due to strictly transversal lateral sepals. Gynoecium development indicates similarities of Eriocaulaceae with restiids and graminids rather than with Xyridaceae.
谷精草科（禾本目）在相对于苞片（中萼片近轴）的花器官排列模式上与可能相关的黄眼草科不同。一些谷精草科植物具有退化且非三轮的花被，但发育数据不足。我们对三种谷精草属植物的花发育进行了扫描电子显微镜研究，以了解在一种萼片高度退化且据报道缺少花冠的谷精草属植物中，器官数量和排列是否稳定。所有三个物种的早期花发育相似。雄花和雌花在早期阶段难以区分。尽管有早期报道，但在该谷精草属植物中，两种花型均一致地具有三个先天联合的萼片和三个花瓣。花瓣和内轮雄蕊由共同原基发育而来。我们认为在谷精草属植物的分类描述中应使用扫描电子显微镜来评估器官数量和排列。在谷精草科中发现了两种花冠退化类型：花瓣抑制和完全缺失。该谷精草属植物中常见的花瓣 - 雄蕊原基不像其他单子叶植物那样与延迟的花托扩展同时出现，而是与花瓣生长迟缓相关。该谷精草属植物“反向”的花取向可能是由于严格横向的侧萼片。雌蕊发育表明谷精草科与帚灯草科植物和禾本科植物相似，而不是与黄眼草科相似。
