Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
82631 | Agricultural and Forest Meteorology | 2009 | 5 Pages |
Abstract
Previous studies on pollen dispersal helped to identify objective parameters of coexistence of genetically modified (GM) and conventional maize. Nevertheless, data on the quantity and dynamics of airborne pollen flow (APF) in air layers above and around a maize field, and its contribution to the rate of cross-pollination, are still missing. In 2004 and 2005, 690 pollen traps were arranged at different locations relative to three maize fields: in the maize fields itself, and in fields adjacent to the maize fields, consisting either of grassland or wheat stubble. The traps were positioned along strings over maize, wheat stubble and grassland at two fixed heights relative to the maize plants: immediately above (0Â m) and 1Â m above tassel height (1Â m). Whereas the traps positioned at 0Â m over maize indicated the amount of pollen shed, those located at 1Â m above tassel height indicated airborne pollen flow to this upper air layer. The amount of pollen at 1Â m relative to the amount of pollen just above the tassel, ranged from 4% to 40%; very high values correlated with strong winds during flowering. These winds were not strong enough to transport significant amounts of pollen farther than a few meters away from the pollen source because above both adjacent grass and wheat stubble environments, the amount of pollen at 1Â m above tassel height was similarly low. In one single experiment and at 0Â m above tassel height, a significantly higher amount of pollen was found over wheat stubble than over grassland. During this experiment, high temperatures and low wind speeds coincided with pollen shed, which may have favored the generation of thermals over hot surfaces, capable of lifting pollen grains.
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Atmospheric Science
Authors
André Vogler, Marianne Wettstein-Bättig, Ingrid Aulinger-Leipner, Peter Stamp,