Fourth National IPM Symposium


Fourth National IPM
Symposium/Workshop
2003



 Session: IPM in Commercial Greenhouses: How Can Biological Control Play a More Prominent Role?
Tuesday 3:30 PM - 5:00 PM
Organizer(s):
Jim Nechols (jrnechol@ksu.edu)


The following presentations are in this session:

3:30 PM - 3:45 PM Introduction and Overview Raymond A. Cloyd


3:45 PM - 4:00 PM Developing an Integrated Crop Management Program for Ivy Geraniums George P. Opit ,  James R. Nechols ,  Kimberly A. Williams ,  David C. Margolies ,  and Yan Chen
    Production of ivy geraniums, a multi-million dollar floricultural crop, is threatened by the twospotted spider mite, Tetranychus urticae Koch. Currently, this pest is managed predominantly with acaricides. However, problems related to pesticide resistance, environment and human health, and governmental regulations suggest the need for developing pest management alternatives for spider mites. Our research takes a broad integrated crop management approach, which includes not only pest management, but seeks to develop the most efficient and environmentally compatible strategy for simultaneously producing and protecting ivy geraniums. Results showed that neither watering practices nor nitrogen fertilizer affected spider mites; but phosphorous had a minor effect on mite populations. We developed a simple presence-absence sampling plan for twospotted mites which enabled us to determine when action thresholds were reached, and to use specific predator-prey release ratios. We determined that a 1:4 or 1:20 (predator:prey) ratio would provide good biological control using the predatory mite, Phytoseiulus persimilis, even when pest populations were initially high.














4:00 PM - 4:15 PM Integrated Pest Management in Greenhouses: Are Pest Control Materials and Natural Enemies Compatible? Raymond A. Cloyd
    Combining natural enemies such as parasitoids and predators with biorational insecticides, including insect growth regulators, insecticidal soaps, and horticultural oils, may be a means to reduce insecticide use in interior plantscapes. In fact, several biorational insecticides state on the label that they are not harmful to natural enemies. However, research investigating both acute and chronic effects has shown that biorational insecticides are harmful to and negatively impact host acceptance, fecundity, attack rate, and foraging behavior of certain natural enemies. This suggests that further research is necessary in order to understand fully the compatibility of biorational insecticides with natural enemies before making recommendations.






4:15 PM - 4:30 PM Scouting for Pests From a Commercial Grower's Perspective Joe Boarini


4:30 PM - 4:45 PM Economic Feasibility of Biological Control for Twospotted Mite on Ivy Geraniums Sara Schumacher ,  Thomas L. Marsh ,  and Terry Kastens
    A bioeconomic model for floriculture production was developed and applied to the greenhouse-grown ivy geraniums (Pelargonium peltatum (L.)’Her ex Ait ), one of its major pests, the twospotted mite, Tetranychus urticae Koch, and a potential predatory mite, Phytoseiulus persimilis. This model incorporated aesthetic quality standards including assessment of pest damage which is important in floriculture production and marketing. Optimal decision rules with respect to nutritional and pest management controls were determined from the empirical model. Results demonstrated that there are circumstances under which combinations of introduced predators and chemical control are economically optimal.








4:45 PM - 5:00 PM Economic Feasibility of Biological Control for Whiteflies on Poinsettias Roy Van Driesche and John P. Sanderson