Pollination mechanism

Anthocyanins typically absorb at 520-560 nm, a region of the spectrum to which mammalian eyes are most sensitive. These compounds are important pigments in flowers and fruits and play major roles in pollination mechanisms and fruit dispersal (Harbome, 1991). Chlorophyll, carotenoids, and phytochrome have minimal absorption in this region. 

Animals live in a world of chemical communication and receive both olfactory and visual cues that indicate appropriate host plants. When the animal has located the flower against the generally green background, it may be attracted to the nectar by nectar guides on the petals. These are derived from differential distribution of pigments within the flower tissue. The biochemistry of plant pollination mechanisms has not been studied extensively. 

Alexandra Ley and Regine Classen-Bockhoff (Chapter 10) study the variation in the elaborate pollination mechanism of Marantaceae. By mapping major... 

In the present chapter we summarize recent phylogenetic and floral structural findings for the Marantaceae. By using additional ecological and geographical data, we reconstruct the major character transformations per node and test the hypotheses of the pollination mechanism being (1) a key innovation for speciation or (2) exclusively a tool for optimization of the mating system. 

Based on the current knowledge there is no indication that the explosive pollination mechanism has acted as an important isolation factor during the evolution of the Marantaceae. The key innovation hypothesis is thus rejected, giving rise to the question of which other forces may have driven speciation. 

Stebbins, G. L. (1970). Adapdve radiadon of reproductive characteristics in angiosperms, 1 pollination mechanisms. Annual Review of Ecology and Systematics, 1,307-326. 

Owens, J.N., S.J. Morris and G.L. Catalano. 1994. How the pollination mechanism and prezygotic and postzygotic events affect seed production in Larix occidentalis. Can. J. For. Res. 24 917-927. 

Gelbart, G., and P. von Aderkas. 2002. Ovular secretions as part of pollination mechanisms in conifers. Annals of Forest Science 59 345-357. 

Owens, J.N., S.l. Simpson and M. Molder. 1981. The pollination mechanism and the optimal time of pollination in Douglas-fir Pseudotsuga menziesii). Canadian Journal of Forest Research 11 36-50. 

Lit. R.Frankel, E.Galun Pollination Mechanism, Reproduction and Plant Breeding Springer Verlag New York (1977)... 

The orchids single benefit from supplying this rich reward is, of course, pollination. To ensure that the orchid bees perform as desired, the plants have devised incredible strategies. There are trigger mechanisms that shoot a pollen packet at the bee with considerable force, knocking him down but ensuring that the packet sticks to his body. There are flowers constructed like the western-prairie fringed orchid, so that a bee picks up a compact mass of... 

Ethylene-dependent mechanism terminates flower life after successful pollination as a way to benefit survival of the species. Usually, in species with short-lived flowers, such an ethylene-dependent termination apparently is not beneficial as the life of individual flowers is short anyway. Similarly, in species with numerous flowers in one flower head in which continuous visits of pollinators are required, ethylene-dependent termination is not beneficial. ... 

Schemske DW, Bradshaw HD (1999) Pollinator preference and the evolution of floral traits in monkeyflowers (Mimulus). Proc Natl Acad Sci USA 96 11910-11915 Wang HC, Huang XM, Hu GB, Yang Z, Huang HB (2005) A comparative study of chlorophyll loss and its related mechanism during fruit maturation in the pericarp of fast- and slow-degreening litchi pericarp. Sci Hortic 106 247-257...

Baker, H. G. (1963). Evolutionary mechanisms in pollination biology. Science 139,877-883. 

One of the best-established functions of anthocyanins is in the production of flower color and the provision of colors attractive to plant pollinators. Considerable effort has been made to give explanations for the color variations expressed by anthocyanins in plants. Various factors including concentration and nature of the anthocyanidin, anthocyanidin equilibrium forms, the extent of anthocyanin glycosidation and acylation, the nature and concentration of copigmentation, metal complexes, intra- and intermolecular association mechanisms, and influence of external factors like pH, salts, etc. have been found to have impact on anthocyanin colors. ... 

Ackerman, J.D. (1986). Mechanisms and evolution of food deceptive pollination systems in orchids. Lindleyana 1 108-113. 

Galen, C., Zimmer, K. A. and Newport, M. E. (1987). Pollination in floral scent morphs of Polemonium viscosum a mechanism for disruptive selection on flower size. 

Schiestl, F. P. and Ayasse, M. (2001). Post-pollination emission of a repellent compound in a sexually deceptive orchid a new mechanism for maximizing reproductive success Oecologia 126 531-534. 

Schiestl, F. R, Ayasse, M., Paulus, H. D. et al. (2000). Sex pheromone mimicry in the early spider orchid (Ophrys sphegodes) patterns of hydrocarbons as the key mechanism for pollination by sexual deception. Journal of Comparative Physiology A 186 567-574. 

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