Environmentally Dependent Morphological Variability in Seven Apomictic Microspecies from Alchemilla L. (Rosaceae)

Abstract

Apomictic microspecies, for example those of the genus Alchemilla, are often difficult to distinguish. Still, their differences are thought to be persistent due to apomixis. Apomicts are argued to have general-purpose genotypes. The present study aims to assess the variation of morphological characters of Alchemilla depending on environmental conditions both in nature and experimentally; to evaluate the efficacy of characters for identifying the different microspecies; to assess the similarity of different microspecies; and to determine if Alchemilla microspecies have general-purpose genotypes that are not dependent on environmental conditions. The variability of selected characters in seven microspecies of Alchemilla was studied in nature and five microspecies were grown in a common garden experiment. The growing conditions of the latter were subjected to various manipulations (fertilization, shading and irrigation). Typical natural habitats of Alchemilla exhibited only small differences. Environmental conditions therefore had little effect on morphological characters. Neither cultivation in the common garden nor manipulation of conditions therein had a significant impact on the discrimination of microspecies. However, the metric characters were larger in the garden relative to those observed in nature, particularly under fertilization. Fertilization affected most characters, whereas shading and irrigation did not. The most effective characters for discriminating between microspecies were the ratios of the metric characters. Two species pairs: A. vulgaris and A. micans, as well as A. glaucescens and A. hirsuticaulis were morphologically close; however, the species within these pairs could still be distinguished. The morphological characters of Alchemilla microspecies were only slightly dependent on the environmental conditions.

Evolution and biogeography of alpine apomictic plants

“…In the majority of cases, genotypes or clones of asexual lineages are restricted to a single locality (reviewed in Hörandl & Paun, 2007). Experimental studies on apomictic plants (De Kovel & Jong, 1999 on Taraxacum;Pihu & al., 2009 on Alchemilla) and parthenogenetic animals (e.g., Gade & Parker, 1997;Robinson & al., 2002;Vorburger & al., 2003) do not confirm a high morphological plasticity under different environmental conditions, and instead show that asexual lineages have rather narrow ecological niches. These studies do not support the "general purpose genotype" hypothesis.…”

Determination of apomixis by flow cytometry in two species of Lachemilla (Rosaceae) in Ecuador

“…Apomictic species are characterized by the formation of microspecies (i.e. populations with morphological variation), which are often problematic for taxonomic determination [10,17,20].…”

Variability of leaf blade characters of some microspecies from <i>Alchemilla</i> L. (Rosaceae) in nature coenopopulations and culture on the territory of Mari El Republic

“…Практически на одном уровне точность классификации A. acutiloba (81%) и A. gracilis (79%). Близость этой пары микровидов показана рядом авторов по результатам исследования морфометрических признаков [22] и анализа генетического полиморфизма [23]. Заключение Получили изображения эталонной конфигурации листовой пластинки для микровидов A. acutiloba, A. gracilis, A. monticola, A. sarmatica, A. schistophylla, A. substrigosa.…”