We report here on a comparative developmental profile of plant hormone cytokinins in relation to cell size, cell number and endoreduplication in developing maize caryopsis of a cell wall invertase-deficient miniature1 (mn1) seed mutant and its wild type, Mn1, genotype. Both genotypes showed extremely high levels of total cytokinins during the very early stages of development, followed by a mark...

The molecular mechanisms responsible for postpollination changes in floral scent emission were investigated in snapdragon cv Maryland True Pink and petunia cv Mitchell flowers using a volatile ester, methylbenzoate, one of the major scent compounds emitted by these flowers, as an example. In both species, a 70 to 75% pollination-induced decrease in methylbenzoate emission begins only after poll...

In the Brassicaceae, intraspecific non-self pollen (compatible pollen) can germinate and grow into stigmatic papilla cells, while self-pollen or interspecific pollen is rejected at this stage. However, the mechanisms underlying this selective acceptance of compatible pollen remain unclear. Here, using a cell-impermeant calcium indicator, we showed that the compatible pollen coat contains signal...

Many flowering plants exhibit an important intraspecific reproductive barrier phenomenon, that is, self-incompatibility (SI), in which S-RNase genes play a significant role. To clarify the specific function of S-RNase genes in Chinese pears, the full length cDNA of PbS 26 -RNase was isolated by rapid amplification of cDNA ends (RACE) technology from Chinese white pear (Pyrus bretschneideri) cul...

Seed set is usually low and differs for different crosses of flower lotus (Nelumbo nucifera Gaertn.). The reasons remain unknown, and this has a negative impact on lotus breeding. To determine the causes, we carried out two crosses of flower lotus, that is, "Jinsenianhua" × "Qinhuaihuadeng" and "Qinhuaihuadeng" × "Jinsenianhua" and pollen viability, pistil receptivity, and embryo development we...

Self-incompatibility (SI) is one of the important factors that can result in seedless fruit in Citrus. However, the molecular mechanism of SI in Citrus is not yet clear. In this study, two suppression subtractive hybridization (SSH) libraries (forward, F and reverse, R) were constructed to isolate differentially expressed genes in pollen from "Wuzishatangju" (SI) and "Shatangju" (self-compatibi...

INTRODUCTION There are many potential factors that can modulate bronchial reactivity, including exposure to allergens, viral infections, and medications. The aim of this study was to analyze the effect of grass pollination intensity on the bronchial reactivity in seasonal allergic rhinitis (SAR) patients subjected to subcutaneous allergenic immunotherapy (SCIT). MATERIAL AND METHODS This stud...

PREMISE OF THE STUDY Changes in the pollinator communities of marginal plant populations can affect their pollination quantity or quality. Geographic variation in pollination success can alter the reproductive advantage that female plants require to persist within gynodioecious populations. Particularly valuable is determining the pollination success at the prezygotic stage in self-compatible g...

Pollination regulates a syndrome of developmental responses that contributes to successful sexual reproduction in higher plants. Pollination-regulated developmental events collectively prepare the flower for fertilization and embryogenesis while bringing about the loss of floral organs that have completed their function in pollen dispersal and reception. Components of this process include chang...