Anther and pollen development are crucial processes of plant male reproduction. Although a number of genes involved in these processes have been identified, the regulatory networks of pollen and anther development are still unclear. EMBRYONIC FLOWER 2b (OsEMF2b) is important for rice development. Its biological function in floral organ, flowering time and meristem determinacy have been well-stu...

We identified the Arabidopsis MALE STERILITY1 (MS1) gene by transposon-mediated mutagenesis. In the transposon-inserted allele ms1-8, normal immature microspores separated from tetrads, but their subsequent maturation was abnormal: the outer layer of the microspore was absent, and both the microspore and the tapetal layer gradually became vacuolated. Empty locules resulted. The MS1 gene was exp...

Sexual reproduction of plants starts with the formation of gametes and a 2-fold reduction in the number of chromosomes (ploidy) of these cells. Fertilization, the union of sperm and egg cell restores the ploidy level to its normal value again. During the formation of pollen grains, the structures that contain the male gametes, the reduction in the number of chromosomes happens when the vegetati...

Pollen fecundity is crucial to crop productivity and also to biodiversity in general. Pollen development is supported by the tapetum, a metabolically active sporophytic nurse layer that devotes itself to this process. The tapetum in cereals and a vast majority of other plants is of the nonamoeboid type. Unable to reach out to microspores, it secretes nutrients into the anther locule where the m...

A spontaneous male-sterile, female-fertile mutation affecting bivalent arrangement at the metaphase plate and cytokinesis was detected in line BR98-197 of the soybean breeding program developed by Embrapa - National Soybean Research Centre. Untill diakinesis, meiosis was normal with chromosome pairing as bivalents. From this phase, in several meiocytes, bivalents were not able to organize a sin...

In flowering plants, male meiosis occurs in the microsporocyte to produce four microspores, each of which develops into a pollen grain. The image at top left is a transmission electron micrograph of a wild-type microspore from Arabidopsis thaliana, showing the single, central nucleus. The tetraspore (tes) mutant of Arabidopsis fails to undergo cytokinesis at the end of male meiosis and all four...

Stamens are the male reproductive organs of flowering plants. They consist of an anther, the site of pollen development, and in most species a stalk-like filament, which transmits water and nutrients to the anther and positions it to aid pollen dispersal. Within the anther, male sporogenous cells differentiate and undergo meiosis to produce microspores, which give rise to pollen grains, whereas...

Twelve accessions of tronchuda cabbage landraces were tested for their ability to produce embryos through microspore culture in NLN-13 medium. A sample from all the isolations was stained with DAPI for determination of microspore developmental stage. The relationship between the microspore developmental stage and the production of microspore-derived embryos was evaluated. Embryos were obtained ...

The pollen cell wall is important for protection of male sperm from physical stresses and consists of an inner gametophyte-derived intine layer and a sporophyte-derived exine layer. The polymeric constituents of the robust exine are termed sporopollenin. The mechanisms by which sporopollenin is anchored onto microspores and polymerized in specific patterns are unknown, but the primexine, a tran...

In a previous review of male gametophyte development (McCormick, 1993), it was noted that the two areas posed by Mascarenhas (1975) as fruitful areas for future research were the following. What are the differences in the two cytoplasms that determine the different cell fates of the generative and vegetative cells? And what are the functions of pollen-specific proteins? Now, 10 years later, the...