Contact:Ben Puttler (puttlerbe@missouri.edu), Wayne Bailey (baileyw@missouri.edu), Tom Clark (clarkth@missouri.edu), Lisa Meihls, Department of Entomology, University of Missouri - Columbia.

Project Description: One new county (Dunklin) was added to the distribution of the soybean aphid (SBA) bring to 70 the total number of counties officially reported infested in Missouri. Although no statewide surveys were conducted, the ease by which the SBA was detected in surveys, in numerous soybean fields in central Missouri, in mid-August indicates that the SBA most likely occurs throughout the state wherever soybeans are grown. The detection of SBA in Dunklin County, which borders Arkansas, lends credence that the SBA can disperse and establish in southern states producing soybeans.

Soybean aphids were apparently non-economic throughout the state except for two fields in northeast Missouri (one each in Ralls and Pike Counties) and both these were treated with subsequent aphid population reduction. In one of these fields, a portion was inadvertently not treated and maintained a large population of aphids in the untreated area. Lady beetles, the 7-spotted (Coccinella septempunctata), multicolored Asian (Harmonia axyridus), and syrphid fly larvae were present and actively feeding on the aphid. In contrast, the minute pirate, but (Orius insidiosus) appeared to be the dominate predator when non-economic populations were present and may be responsible in preventing significant increases of the SBA in most soybean fields.

Parasites of the SBA were not detected under non-economic field conditions at the UMC-South Farm at Columbia (Boone County), Missouri. Yet the Aphidiinae wasp (Lysiphlebus testaceipes) was attracted to a heavy population of SBA that developed under caged conditions. Parasitization was light and many of the L. testaceipes mummies were hyperparasitized by Asaphes vulgaris (Pteromalidae) and Alloxystra sp (Charipidae). H. Testaceipes as well as the hyperparasites are previously known from the locality parasitizing the cowpea aphid (Aphis craccivora) that infested alfalfa.

Another Aphidiinae parasite, the non-indigenous Aphidus colemani, which was purchased from a commercial insectary and released against an infestation of the corn leaf aphid (Rhopalosiphum maidis) at one end of a greenhouse, dispersed to the other end and parasitized the SBA. It was hyper-parasitized by the same species as L. testaceipes.

2) Project title: Diseases of Insects

Contact: Ben Puttler (puttlerbe@missouri.edu), Department of Entomology, University of Missouri - Columbia.

Project Description: It was previously reported that the milky disease found in northern masked chafer (Cyclocephala borealis) grubs was determined as Paenibacillus lentimorbus. It now appears that the disease organism may be P. Popilliae. A specific identification is being pursued.

As in past years, all grubs collected alive from the turf grass surface this year (2003) died of the milky disease within 96 hours. They first appeared in September of this year in contrast to October in past years.

3) Project title: Lacebugs: Corythucha sp.

Contact: Ben Puttler (puttlerbe@missouri.edu), Department of Entomology, University of Missouri - Columbia.

Project Description: A parasite, Anagrus takeyanus (Mymaridae), was reared from the eggs of the oak lace bug (Corythucha acurata) collected on bur oak located on the University of Missouri - Columbia Campus (Boone County) and at the University’s Horticulture and Agroforestry Research Center at New Franklin (Howard County), Missouri. This represents a new host and state record for the parasite. Studies are planned to determine parasite phenology, distribution and relationship to other species of lace bugs.

4) Project title: Hypera postica (Alfalfa weevil), H. meles (clover head weevil), H. Nigrirostris (lesser clover leaf weevil)

Contact: Ben Puttler (puttlerbe@missouri.edu), Department of Entomology, University of Missouri - Columbia.

Project Description: No fall (2002) non-diapausing adult alfalfa weevils were available for collection from three central Missouri alfalfa fields in contrast to the availability of spring (2003) weevils. From a total 1,015 adults dissected, 11.1% were parasitized by Microoctonus aethiopoides. This percentage was more than twice obtained in previous years (ca. 5%). The majority of parasitization occurred in weevils collected between April 23 and April 30.

As in 2002 the lesser clover leaf and clover head weevils were scarce. From a total 41 adults of both species, 2.4% were parasitized by M. aetheopoides.

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Cline, A. R., F. W. Shockley, and B. Puttler. 2002. Description of Surface Swimming by Hypera eximia Le Conte (Coleoptera: Curculimidae): Behavioral, Morphological, and Phylogenetic Implications. Ann. Entomol. Soc. Amer. 95: 637-645.

Puttler, B. and W. C. Bailey. 2003. Establishment of Oomyzus gallerucae (Hymenoptera: Eulophidae) an Egg Parasite of the Elm Leaf Beetle (Coleoptera: Chrysomelidae) in Missouri and Adjacent States. Biological Control. 27: 20-24.

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