PARENT SESSION
Poster Session 24: Agro-Ecology
Wednesday, August 10, 5:00 PM - 6:30 PM, Exhibit Hall 220 A-E, Level 2, Palais des congrès de Montréal

Activity cycles and vertical stratification of spiders in cornfields.

Homsher, Ryan¹, Cady, Alan^*,1, ¹ Miami University, Oxford, OH, USA

ABSTRACT- Spiders are generalist predatory arthropods increasingly studied for their potential use as agents of biological control. Spider distributions and abundances over the diel period have been studied in various row crops, but have been poorly investigated in corn. Placing discrete habitat refugia (small straw piles) in soy and corn fields increases crop yield and lowers plant damage, but the mechanism behind the refugia effect is not clear. One hypothesis is that there is a difference in abundance and composition of spider assemblages associated with corn plants near refugia. Furthermore, it is unknown if certain families of spiders prefer specific areas on corn plants, as has been found in other crops. Thus, a nine-week observational study of spiders on and around corn plants was conducted to determine spider community composition, their positions on the plants, and their activities throughout the diel period relative to refugia. Current analyses show trends for spatial and temporal partitioning (height on plants) of spiders in the cornfields. No clear differences of spider numbers between control and refugia areas are presently apparent.

Key words: spiders, agroecosystems, corn, Integrated Pest Management