1) Project title: Nutritional Ecology of Aphidophagous Coccinellids in the High Plains

Investigators: J.P. Michaud, J. A. Qureshi, J. Nechols

Contact: J.P. Michaud (jpmi@ksu.edu)

Project description: We are examining the nutritional ecology of H. convergens in the High Plains region. We have found that overwintered adults give rise to a relatively synchronous first generation in spring, timed to coincide with aphid population development in winter wheat. These first generation adults exit fields en masse as the wheat matures and dries down. In the absence of abundant aphid prey, female adults enter a reproductive diapause of indeterminate duration. This is cued by food quality and availability; females encountering abundant aphid prey imediately do not enter diapause, but alternative animal and plant protein sources are not sufficient to prevent diapause in most females. Diapausing beetles acquire water and some basic nutrients by drinking the sap of certain herbaceous plants such as sunflower, enabling them to survive many months even through very hot, dry summers. The reproductive diapause of females decays naturally over summer months and this decay is accelerated by access to animal protein food sources (alternative, non-aphid prey) but maximum reproductive success is only obtained when aphids (Schizaphis graminum, Rhopalosiphum padi, or Diuraphis noxia) are the primary food source. When aphids are abundant, females that have been in reproductive diapause as long as 3-4 months are still able to produce as many as 1500 eggs or more with fertility of 75-85 %. These phenomena results in an indeterminate number of potential generations each season depending on aphid abundance; at least two, but possibly as many as four or five. We suspect that this facultative voltinism mediated by reproductive diapause is key to the success of H. convergens in the High Plains, as this behavior is not demonstrated by other native species such as Cycloneda munda and Coleomegilla maculata that never achieve the abundance of H. convergens in this environment.

2) Project Title:Biological Control-Based Integrated Crop Management on Greenhouse Floricultural Bedding Plants

Subproject 1: Evaluation of mechanical blowers for distributing predatory mites of greenhouse pests.

Investigators:George P. Opit, James R. Nechols, David C. Margolies, and Kimberly A. Williams

Contact:Jim Nechols (jnechols@ksu.edu)

Project Description: Greenhouse experiments revealed the technical and economic advantages of using a mechanical blower compared to hand-releasing the spider mite predator, Phytoseiulus persimilis. Results also showed that a blower without a metering device resulted in higher survival of both P. persimilis and another predatory mite, Amblyseius cucumeris, which is used to control the western flower thrips. Dispersal ranges of both predators were quantified for both mechanical blowers.

Subproject 2: Effects of plant age, fertilization and predator:prey release ratios on damage response of ivy geranium to twospotted mites.

Investigators: George P. Opit, Yan Chen, Kim Williams, Jim Nechols, and David Margolies

Contact: George Opit (george.opit@gmprc.ksu.edu)

Project description: Greenhouse experiments showed that younger ivy geranium exhibited more damage from the twospotted spider mite, Tetranychus urticae, than older plants. Nitrogen and phosphorous, when applied in various combinations over the range of fertilizer concentrations used to produce high-quality plants, had no effect on spider mite populations or plant damage. An evaluation of biological control of spider mites using the predatory mite, Phytoseiulus persimilis, at various release ratios showed that predator:prey ratios of 1:4 and 1:20 resulted in good plant protection; whereas unacceptable damage occurred at a release ratio of 1:60.

3) Project Title: Comparison of Trichogramma spp. at different patch scales on biological control of the Indian Meal Moth, Plodia interpunctella.

Investigators: Matt Grieshop, Paul Flinn, James Nechols (Dept. of Entomology, Kansas State University).

Contact:Paul Flinn (paul.flinn@gmprc.ksu.edu)

Project Description:A series of experiments were conducted at various spatial scales, including a simulated retail store environment, to compare the foraging efficiency and impact of three Trichogramma species (T. deion, T. pretiosum and T. ostriniae) on the Indianmeal moth, Plodia interpunctella. Results indicated that T. deion would be the best choice for augmentative biological control of the Indianmeal moth. Gondola shelves had a negative effect on host-finding by all Trichogramma species compared to open shelves, suggesting that additional parasitoids may need to be released in environments with gondola shelving. An experiment conducted with single or dual releases of Trichogramma deion and the larval parasitoid, Habrobracon hebetor, suggested that both parasitoids should be released where packaged grain is present. T. deion is highly effective on smooth surfaces of packaging, whereas H. hebetor is highly effective on spilled grain and can also penetrated perforated packages to control P. interpunctella

Dissertation: Grieshop, Matthew J. 2005. Evaluation of Trichogramma spp. as egg parasitoids for the biological control of the Indianmeal moth in retail stores and warehouses. Ph.D Dissertation, Kansas State University, Manhattan..

4) Project Title: Interaction of carriers and insecticides on the efficacy of Beauveria bassiana against the Red Flour Beetle.

Investigators:Waseem Akbar, Jeffrey Lord, James Nechols

Contact: Waseem Akbar (wakbar@agcenter.lsu.edu)

Project Description: Laboratory experiments to test the efficacy of the fungal pathogen, Beauveria bassiana, against the red flour beetle (Tribolium castaneum) showed that when the pathogen was applied alone or in a solution of the wetting agent, Silwet, the median concentration of conidia required to kill red flour beetles was twice that of applications of B. bassiana combined in mineral oil. The insecticide, Neemix 4.5, reduced the efficacy of B. bassiana in 2 of 4 trials. When the insecticide, Hexacide, was applied in combination with B. bassiana, there was no increase in T. castaneum mortality over that with the insecticide alone.

Back to top of web page

Akbar, W., J.C. Lord, J.R. Nechols, and T.M. Loughin. 2005. Efficacy of Beauveria bassiana for red flour beetle when applied with plant essential oils or in mineral oil and organosilicone carriers. J. Econ. Entomol. 98: 683-688.

Michaud, J.P. 2005. On the assessment of prey suitability in aphidophagous Coccinellidae. Eur. J. Entomol. 102: 385-390.

Michaud, J.P. & A.K. Grant. 2005. Suitability of pollen sources for development and reproduction of Coleomegilla maculata (Coleoptera: Coccinellidae) under simulated drought conditions. Biological Control 32: 363-370.

Michaud, J.P. & Qureshi, J.A. 2005. Induction of reproductive diapause in Hippodamia convergens (Coleoptera: Coccinellidae) hinges on prey quality and availability. Eur. J. Entomol. 102: 483-487.

Opit, G.P., J.R. Nechols, D.C. Margolies, and K.A. Williams. 2005. Survival, horizontal distribution, and economics of releasing predatory mites (Acari: Phytoseiidae) using mechanical blowers. Biological Control 33:344-351.

Opit, G.P., Y. Chen, K.A. Williams, J.R. Nechols, and D.C. Margolies. 2005. Plant age, fertilization and biological control affect damage caused by twospotted spider mites on ivy geranium: development of an action threshold. J. Amer. Soc. Hort. Sci. 130: 159-166.

Back to top of web page

View reports from other state