News Summer 2011

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In the National News


The eggs and larvae of alfalfa leafcutting bees, Megachile rotundata, have been shown to have at least 84% mortality when female bees have been exposed to the insect growth regulator novaluron (Rimon), which is often used to control lygus bugs. It is thought that use of novaluron in alfalfa grown for seed could contribute to decreasing populations of bees. The full article, published in the most recent Journal of Insect Science, can be read by clicking here.


USDA Agricultural Research Service scientists have released three parasitoid wasp species (Oobius agrili, Tetrastichus planipennisi, and Spathius agrili) in six midwestern and eastern states for control of emerald ash borer. The wasps are still being evaluated for winter survival in northern states, although T. planipennisi has already been found to persist in Michigan sites. It is also the most abundant wasp species attacking the borer a year after release. Scientists are also looking at the fungus, Beauveria bassiana, as a possible biocontrol. It has been shown to kill the adults when sprayed on infested trees, persists on the bark, and is safe on the predator wasps.


The brown marmorated stink bug, introduced from Asia, has become a serious pest in the eastern U.S., where its feeding on fruit in the mid-Atlantic region resulted in $37 million in losses in 2010. They are becoming difficult to treat with insecticides, and native predators appear to avoid them. Recently, however, USDA Agricultural Research Service entomologists identified four species of Trissolcus wasp that feed exclusively on the brown marmorated stink bug in China, Japan, and Korea. These parasitoids target stink bug eggs, laying their own eggs inside, where the developing larvae feed on the stink bug egg contents until pupation. The behavior of the wasps is currently being studied in the lab. Release of the wasps into infested sites may be a possibility in about 2 years.


A national network will soon be formed called the Bee Informed Partnership, thanks to a $5 million USDA grant to Penn State University. The project will focus on a number of activities to reduce losses due to Colony Collapse, including the development of best management practices, a variety of surveys, an alert and reporting system, and a dynamic honey bee health website. Thirteen other universities and agencies across the U.S. are part of the project.


Scientists are realizing the importance of native bees in agriculture and wild settings. Very little is known about the distribution of native pollinators, and a recent U.S. Geological Survey study found that the location of certain native solitary bees is not related to plant community composition, which is not as one would suspect. The study identified close to 5,000 bee species in five different habitats in Indiana. They found that local factors and micro-habitats, such as abundance of dead wood, soil characteristics, whether the area had burned, etc., are as important as diversity of plants in determining bee diversity. The total number of bees found was lowest in wooded areas and highest in recent burns. Bee diversity was highest in less wooded areas that had a high plant diversity and abundance of nesting locations. The study will continue in national parks to see how climatic variation affects native bees.


For the first time, the interaction between insect feeding and subsequent plant host defenses has been identified. USDA scientists in Gainesville, Florida, have identified a mechanism in plants that triggers a defense response to insect feeding. Some insects secrete saliva as they feed, and after the first feeding on a host plant, the saliva will contain plant proteins that are recognized by the plant. Identified as an amino acid called inceptin, the protein in the insect secretion acts as an SOS, launching plant defense chemicals. This discovery could lead to the development of plants with improved protection against insect pests.


Useful Publications and Web Sites

• Pest Management Professional published a new online edition of their magazine which focuses on the management of ants. Click here for the publication.

• A recent publication from the Iowa State University informs small fruit growers how to harvest and store their crops at the peak of quality and flavor. Click here to
access the site.