A population of the whitefly Bemisia tabaci has become one of the world’s worst invasive pests – devastating many crops in China and elsewhere in the process – through mating behaviors that help it invade the territory of native whitefly populations, according to a new study conducted in China and Australia.
These findings will be published online by the journal Science, at the Science Express website, on 8 November, 2007. Science is published by AAAS, the nonprofit science society.
The researchers report that the invasive whiteflies are successful at least in part because they breed more when they come into contact with native whiteflies, and they also suppress the native whiteflies’ reproduction rates.
The study demonstrates that behavior can play a critical role in animal invasions, the authors say. Understanding the invasion process is important for pest management, because it helps researchers make accurate estimates of how rapidly and to what extent an alien pest can be expected to invade and displace its native relatives.
The whitefly species, B. tabaci, consists of many different genetic groups or “biotypes.” Biotype B, which probably originated in the Mediterranean-Asia Minor region and has spread through much of the world, is the one considered to be among the world’s worst agricultural pests.
The insect reached Australia in the early 1990s and China in the mid-1990s, through the transport of ornamental and other plants. It affects many different types of crops, causing damage by feeding on plant leaves and spreading viral infections.
“The invasive pest reported in our paper is currently devastating China's agriculture and environment,” said lead author Shu-Sheng Liu of Zhejiang University in Hangzhou, China. “As China's agriculture is more fragile than that of many developed countries, I expect the damage here will be much more severe and will continue for many years. I just returned from a three-day field trip, it was sad to see many tomato growers in Zhejiang are suffering complete loss of their entire crop this season due to this pest and the viruses it transmits,”.
Dr. Liu and his colleagues conducted regular field sampling of whitefly populations in Zhejiang, China, from 2004 to 2006, and in Queensland, Australia, from 1995 to 2005, to monitor the B biotype whitefly behavior as it spread and displaced native whiteflies in the two regions.
They also conducted experimental population studies, simulating the displacement process on caged cotton plants. And, they developed a specialized video recording system to observe and analyze the insects’ movement as well as the mating interactions between alien and native whiteflies on live plants.
The authors identified what they call an “asymmetry” in mating interactions between the invader and native whiteflies, whereby female biotype B whiteflies copulated with biotype B males more frequently when native whiteflies were also present. And, though male biotype B whiteflies didn’t copulate with native females, they did court the native females, interfering with copulation between native males and females.
Innovative genetic tests for children with developmental disorders and epilepsy
11.07.2018 | Christian-Albrechts-Universität zu Kiel
Oxygen loss in the coastal Baltic Sea is “unprecedentedly severe”
05.07.2018 | European Geosciences Union
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
13.07.2018 | Event News
13.07.2018 | Materials Sciences
13.07.2018 | Life Sciences