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In the present study, physiological and biochemical responses of Dunaliella salina exposed to acrylamide were investigated. The indicators were as follows: the growth, photosynthetic pigments, the contents of carbohydrate and protein, antioxidant system of Dunaliella salina. Besides, the ultrastructure and cell cycle distribution were also analyzed. The results showed that acrylamide could significantly inhibit the growth of D. salina (P

The study observed the pollen morphology and ontogeny of Maianthemum bifolium (L.) F.W. Schmidt and explored the development and structure of its anther wall using conventional paraffin section and histochemical techniques. The results showed that it has four anthers, consecutive cytokinesis, tetragonally arranged microspore tetrads, two-celled mature pollen grains, and a secretory tapetum. Fascicular crystals were found in the connective tissues and anther wall during pollen ontogeny. The distribution of carbohydrates and lipids changes regularly in the process of pollen development and is related to their physiological activities such as cell division and material synthesis. Under a light microscope, its pollen grains are ellipsoid and have a sulcus and exine with fine, reticulate ornamentation.

Microsporogenesis and development of the male gametophyte of Allium senescens L. were studied by use of paraffin sections. The anther was found to be four-sporangia. Its wall includes four layers: epidermis, endothecium, middle layer, and secretory tapetum. Cytokinesis during meiosis of microspore mother cells (MMCs) is successive. Most mature pollen grains are two-celled, a few are three-celled. In addition, anomalies were observed during meiosis of MMC and in uninucleate microspores, including laggard chromosomes, lagging chromosomes, anaphase bridges, and micronucleus. These anomalies are possible reasons for abortive pollen.

In this article, we studied the pollen morphology and wall development, microsporogenesis, male gametophyte development, and anther wall structure changes during pollen development of Cardiocrinum giganteum (Wall.) Makina from the genus Cardiocrinum (Endl.) Lindl. (Liliaceae) using paraffin sections, scanning and transmission electron microscopy, and fluorescence microscopy. The results showed that C. giganteum has oval-shaped pollen with a single sulcus and reticulate ornamentation. The exine is of the semi-tectum type and can be divided into the tectum layer, columellate layer and basal layer. Meiosis in the microsporocyte is accompanied by successive cytokinesis. The mature pollen is three-celled. The anther wall prior to maturity is built by one layer of epidermis, 1–2 layers of endothecium cells, 4–5 middle layers and 2 layers of tapetum, while upon maturity it is only built by one layer of epidermis, one layer of endothecium cells and one middle layer. The tapetal cells are secretory, with two or more nuclei. Ubisch bodies originate from rough endoplasmic reticulum except a few from mitochondria.

In this study, pollen morphology of 11 taxa of Hosta in China, three Chinese species, five introduced species, and three cultivars, was observed by scanning electron microscopy (SEM) and compared with that of related genera (Hemerocallis, Agave, and Yucca). Pollen grains of Hosta were long-ellipsoidal or ellipsoidal, 20–65 × 52.5–142.5 μm in size, bilaterally symmetrical, and monosulcate on the distal face. Reticulate and rugulate exine ornamentation was observed in different taxa, and the rugulate type can be further divided into rugulate, rugulate–baculate, and rugulate–granulate subtypes. The exine ornamentation may have evolved in the order: reticulate → rugulate → rugulate–baculate → rugulate–granulate. Furthermore, the rugulate exine ornamentation was the predominant ornamental type in Hosta except for one species with the reticulate type; this is markedly different from that of Hemerocallis, Agave and Yucca. Thus, our data support the proposal by Dahlgren and Clifford (The Monocotyledons: a comparative study. Academic Press, London, 1982) that these Hosta species constitute an independent family–Hostaceae.