Pollen presentation theory (PPT) allows for a re-examination of some classic themes in pollination biology. Here, we outline its implications in the context of beeand birdadapted species of Penstemon and Keckiella (Scrophulariaceae). PPT models the optimal schedule of pollen presentation, based on the frequency of visits by pollinators, and the capacities of those pollinators to remove and depo...

Sexual reproduction in plants requires development of haploid gametophytes from somatic tissues. Pollen is the male gametophyte and develops within the stamen; defects in the somatic tissues of the stamen and in the male gametophyte itself can result in male sterility. The maize fuzzy tassel (fzt) mutant has a mutation in dicer-like1 (dcl1), which encodes a key enzyme required for microRNA (miR...

Sexual reproduction is a critical process in the life-cycle of plants and very sensitive to environmental perturbations. To better understand the effect of high temperature on plant reproduction, we cultivated tomato (Solanum lycopersicum) plants in continuous mild heat. Under this condition we observed a simultaneous reduction in pollen viability and appearance of anthers with pistil-like stru...

The accumulation of proline in anthers of Petunia was followed during flower bud development. Accumulation proceeded continuously from the microspore stage to anthesis except for an intervening period when bud length was between 15 and 35 mm. The second rise in proline content co­ incided with the stage of anther desiccation. The metabolism of proline 3 lA was studied in isolated branches fed w...

Among the >200 members of the leucine-rich repeat receptor kinase family in Arabidopsis thaliana, only a few have been functionally characterized. Here, we report a critical function in anther development for the SOMATIC EMBRYOGENESIS RECEPTOR KINASE1 (SERK1) and SERK2 genes. Both SERK1 and SERK2 are expressed widely in locules until stage 6 anthers and are more concentrated in the tapetal cell...

The maize (Zea mays) spikelet consists of two florets, each of which contains three developmentally synchronized anthers. Morphologically, the anthers in the upper and lower florets proceed through apparently similar developmental programs. To test for global differences in gene expression and to identify genes that are coordinately regulated during maize anther development, RNA samples isolate...

In flowering plants, the meiocytes develop within nourishing tissues – the anthers or the ovaries. Although most plants bear one or more anthers in each bisexual or male flower, the size of anthers that undergo meiosis is relatively small, and each anther contains only a small fraction of male meiocytes. As a consequence, the isolation of plant meiocytes is very challenging due to their relativ...

Different experimental conditions have been compared to achieve a high efficiency in embryogenic calli initiation from 'Macabeo' and 'Tempranillo' anthers. Specifically, two stages of anther development were tested (corresponding to tetrad cells or uninucleate pollen), and direct culture of anthers was compared to culture after a cold treatment of inflorescences (4 °C during 48 h). In addition,...

Molecular mechanisms governing development of the male reproductive organs of flowers, the anthers, are largely unknown. In this article, we report on the investigation of the molecular basis of a mutation involving the expression of a gene encoding the flavonoid biosynthesis enzyme chalcone flavanone isomerase (CHI) in anthers of petunia. In petunia, the gene Po regulates the expression of CHI...