Micromorphological characters variation of lemma and palea in subtribe of Loliinae (Poaceae)

Light and scanning electron microscopy observations on morphological diversity of Rosaceae stigma and its taxonomic significance

The stigma morphology can provide a reference for exploring plant systematics and pollination biology. In this study, we observed the stigma morphological characteristics of Rosaceae in Beijing urban area in detail using light microscopy and scanning electron microscopy. The stigma of Rosaceae is entire or bilobed and mostly baculate, crateriform, cristate, discoid, or flattened. The stigma surface may have irregular, strongly raised ridges; or flat without papillae; or composed of densely or loosely arranged papillary cells. Surface ornamentation includes fossulate, psilate, psilate-striate, rugulate, scabrate, striate, and striate-rugulate. There are similarities in stigma morphology among genera and differences in stigma morphology among species within genera. The stigma shape supports the view of molecular systematic classification, that is, the former subfamilies Maloideae, Prunoideae, and Spiraeoideae are grouped into subfamily Amygdaloideae.

Implications of foliar epidermal micromorphology using light and scanning electron microscopy: A useful tool in taxonomy of Korean irises

The genus Iris L., comprising approximately 210 species, is one of the most species-rich genera in the family Iridaceae. In this study, the first comprehensive leaf micromorphological characters of Korean irises were studied using light and scanning electron microscopy. Our objective was to evaluate the foliar micromorphological characteristics (namely epidermal cells, stomata types, and guard cell size) of Korean Iris taxa in a systematic context. All the investigated Korean Iris taxa had amphistomatic or hypostomatic leaves with anomocytic stomatal complexes. Guard cell length varied among species, ranging from 24.8 μm (I. rossii) to 56.0 μm (I. domestica). Although the presence of papillae on the outer periclinal wall is not of taxonomic significance, leaf margin pattern, guard cell size, and sunken stomata type were useful for species-level identification of Korean Iris species. The occurrence of polymorphic stomatal types was reported here for the first time, and the correlation between genome size and epidermal guard cell length was discussed.

The morphology of stigma of Asteraceae observed by scanning electron microscopy

The morphology of stigma has taxonomic values. To further explore the taxonomy of family Asteraceae, the morphological characteristics of stigma of 28 genera, 32 species, and two varieties in the family were observed using scanning electron microscopy. The results indicated that the stigma morphology of these Asteraceae plants could be divided into 10 types, of which eight are reported for the first time. The morphological characteristics of stigma support the close relationship between genera Aster and Erigeron and among genera Sonchus, Taraxacum, and Youngia. Our results enriched the stigma type diversity data and provided a morphological basis for the study of the phylogenetic evolution of Asteraceae.