These connections are believed to be routes of transport for substances between tapetal cells and the plasma membrane and cytoplasm in both pollen grains and spores. In Selaginella, "wicks" which are plasmodesm
With the origin of pollination in ancient seed plants, the male gametophyte (“pollen”) began to evolve a new and unique life history stage, the progamic phase, a post-pollination period in which pollen sexual maturation occurs in interaction with sporophyte-derived tissues. Pollen performance tr...
Some observations are also reported from pollen development and structure in the South American species Laurelia sempervirens, mature pollen of which can be distinguished from that of L. novae-zelandiae. The aperture begins to develop while pollen of L. novaezelandiae is still in tetrads, and ...
One of the distinguishing features of the Brassicaceae family is the structure of their flowers, which are four-petaled and arranged in a cross shape. This makes the pollen collection and analysis quite similar across the plant family and enabled us to develop one crop-specific chip for the ...
A typical anther is bilobed. It is a tetragonal structure consisting of four microsporangia. These microsporangia form pollen sac which on maturity gets filled with a pollen grains. Pollen grains represent the male gametophytes, their cell wall is very hard. Pollen grains of many species cause...
Surface features and observation of microbial presence onP. radiatapollen was examined under a scanning electron microscope (SEM). Fresh pollen grains were initially sputter-coated with palladium (Emitech K975X coater) before being placed in a JEOL JSM IT-300 variable pressure SEM. Microscopy was ...
Pollen grains from wild-type and transgenic lines were stained with I2–KI solution. The results were shown in Fig. 2. The majority of pollen grains from the 35S-Zm908s anthers were malformed and the pollen I2–KI staining rate was dra- matically reduced. In ...
Above all, half of the pollen grains in F1 hybrids were aborted because of failure during the first mitosis, little starch accumulation and defects in pollen wall structure. To investigate the developmental defects of embryo sacs in the F1 hybrids, confocal laser scanning microscopy was used to ...
Considering the higher expression of CsALC in male gametophytes (Fig. 1e), we first investigated the pollen devel- opment and viability by Alexander staining and in vitro germination assays. As shown in Supplementary Fig. 2d, Csalc pollen grains were morphologically normal and able to germinate...
Most pollen consists of a single grain, which is sometimes connected to two or more grains (Komosińska-Vassev et al., 2015). Pollen grains considerably differ in shape and size. In the dry state, these are mostly spherical or spindle-shaped formations, and after swelling, they may have ...