Irradiated, sterile flies dropped over seaports and agricultural areas to mate with unsuspecting females save food crops and millions of dollars in prevented infestations and the ensuing eradication efforts.
But blasting these secret-suitor insects with radiation via electron beams, X-rays or gamma-rays, tends to make them weaker than typical males — and not so appealing to females as possible mates.
UF/IFAS photo by Marisol Amador
University of Florida insect physiologist Daniel Hahn displays the type of flies used to protect valued crops, in what is known as the sterile insect technique.
What sterile-insect operations need, says University of Florida insect physiologist Daniel Hahn, is the insect world’s version of George Clooney: 52 years old, gray-haired and still dazzling the ladies. Hahn, an associate professor with UF’s Institute of Food and Agricultural Sciences, and his former postdoctoral associate, Giancarlo López-Martínez, now an assistant professor at New Mexico State University, describe in research publications this month and last, that sterilizing insects in a low-oxygen environment helps create suitors who more closely resemble the suave Clooney than do those sterilized in a normal-oxygen environment.
“Our males (insects) are not only more sexually competitive, they are maintaining their sexual competitiveness and their virility, into old age,” Hahn said, “and that has the potential to make them much better biological control agents.”
The sterile insect technique, or SIT, has been used for decades and is considered a much preferable alternative to spraying pesticides over urban or suburban areas near major ports. In this biological control method, large numbers of sterile, male insects are released to compete with wild males for the attention of invasive wild females.
A female duped into accepting a sterile male would then find herself without offspring, thus trimming the population and its threat to the state’s important agricultural crops. The technique has been used effectively against the Mediterranean fruit fly, called the Medfly, and the cattle-infesting screw-worm fly, among others.
Florida spends roughly $6 million a year using SIT to prevent Mediterranean fruit fly infestations, while California spends about $17 million a year. Because of the inherent dangers in importing even one Mediterranean fruit fly into the state, in their recent studies, López-Martínez and Hahn investigated the physiological effects of applying low-oxygen treatments prior to and during irradiation sterilization on two other plant pests: the Caribbean fruit fly and the invasive cactus moth.
The “low-oxygen effect” has been known for decades, but the physiological basis for it had never been rigorously tested or analyzed, Hahn said. They suspected, and found, that under the low-oxygen conditions, the insects’ cells would produce antioxidants that can help better protect them from the off-target radiation damage.
Some operations that rear and sterilize insects, such as one in Guatemala that produces many of the sterile medflies dropped over Florida’s major ports roughly every seven days, do employ low-oxygen conditions, called hypoxia or anoxia. But many others don’t, he said, including those who rear and sterilize the cactus moth.
The reseachers found using a low-oxygen environment during sterilization boosted the sterile males’ longevity as well as their ability to attract and successfully mate. They found that the positive effects of low-oxygen treatments even extended into their ‘old age’ – in the insects’ case, about 30 days under cushy laboratory conditions.
Treatments that both improve the sexual performance of sterile males and maintain high performance longer in older males can substantially increase the effectiveness and decrease the economic costs of SIT programs, Hahn said.
The January paper was published by PLoS One, and the February paper in the Journal of Economic Entomology. Hahn and López-Martínez were joined as authors of that paper by James Carpenter of the USDA’s Agricultural Research Service in Tifton, Ga., and Stephen Hight of the USDA-ARS at Florida A&M University in Tallahassee.
Mickie Anderson | newswise
Farming with forests
23.09.2016 | University of Illinois College of Agricultural, Consumer and Environmental Sciences (ACES)
Ecological intensification of agriculture
09.09.2016 | Julius-Maximilians-Universität Würzburg
The Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP has been developing various applications for OLED microdisplays based on organic semiconductors. By integrating the capabilities of an image sensor directly into the microdisplay, eye movements can be recorded by the smart glasses and utilized for guidance and control functions, as one example. The new design will be debuted at Augmented World Expo Europe (AWE) in Berlin at Booth B25, October 18th – 19th.
“Augmented-reality” and “wearables” have become terms we encounter almost daily. Both can make daily life a little simpler and provide valuable assistance for...
With the help of artificial intelligence, chemists from the University of Basel in Switzerland have computed the characteristics of about two million crystals made up of four chemical elements. The researchers were able to identify 90 previously unknown thermodynamically stable crystals that can be regarded as new materials. They report on their findings in the scientific journal Physical Review Letters.
Elpasolite is a glassy, transparent, shiny and soft mineral with a cubic crystal structure. First discovered in El Paso County (Colorado, USA), it can also be...
For the first time, Fraunhofer IKTS shows additively manufactured hardmetal tools at WorldPM 2016 in Hamburg. Mechanical, chemical as well as a high heat resistance and extreme hardness are required from tools that are used in mechanical and automotive engineering or in plastics and building materials industry. Researchers at the Fraunhofer Institute for Ceramic Technologies and Systems IKTS in Dresden managed the production of complex hardmetal tools via 3D printing in a quality that are in no way inferior to conventionally produced high-performance tools.
Fraunhofer IKTS counts decades of proven expertise in the development of hardmetals. To date, reliable cutting, drilling, pressing and stamping tools made of...
At AKL’16, the International Laser Technology Congress held in May this year, interest in the topic of process control was greater than expected. Appropriately, the event was also used to launch the Industry Working Group for Process Control in Laser Material Processing. The group provides a forum for representatives from industry and research to initiate pre-competitive projects and discuss issues such as standards, potential cost savings and feasibility.
In the age of industry 4.0, laser technology is firmly established within manufacturing. A wide variety of laser techniques – from USP ablation and additive...
Every three years, the plastics industry gathers at K, the international trade fair for plastics and rubber in Düsseldorf. The Fraunhofer Institute for Laser Technology ILT will also be attending again and presenting many innovative technologies, such as for joining plastics and metals using ultrashort pulse lasers. From October 19 to 26, you can find the Fraunhofer ILT at the joint Fraunhofer booth SC01 in Hall 7.
K is the world’s largest trade fair for the plastics and rubber industry. As in previous years, the organizers are expecting 3,000 exhibitors and more than...
23.09.2016 | Event News
20.09.2016 | Event News
16.09.2016 | Event News
26.09.2016 | Materials Sciences
26.09.2016 | Materials Sciences
26.09.2016 | Materials Sciences