Author
Tillman, Patricia - Glynn | |
Carpenter, James |
Submitted to: Environmental Entomology
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 11/20/2013 Publication Date: 4/1/2014 Citation: Tillman, P.G., Carpenter, J.E. 2014. Milkweed (Gentianales: Apocynaceae): A farmscape resource for increasing parasitism of stink bugs (Hemiptera: Pentatomidae) and providing nectar to insect pollinators and monarch butterflies. Environmental Entomology. 43(2):370-376. Interpretive Summary: Stink bugs are primary pests responsible for millions of dollars in losses and cost of control in many vegetable and row crops. Generally, in this region, corn, peanut, and cotton are grown close together in farmscapes. In peanut-cotton farmscapes, stink bugs, i.e., the southern green stink bug, the brown stink bug, and the green stink bug develop in peanut and then move into cotton to feed on bolls. The main objective of this study was to examine the impact of a habitat of tropical milkweed on the biological control of stink bugs in cotton. Stink bug density and parasitism rates were monitored in cotton plots with or without milkweed habitats in 2009 and 2010. The milkweed habitat consisted of 25 potted flowering plants 4 ft. apart along the edge of cotton. The milkweed habitat increased bug parasitism by Trichopoda pennipes (F.) for both years. In the first year of the study, there was some indication that this sole management strategy can help keep stink bugs below economic threshold in this crop. Complimentary management strategies, though, may also need to be incorporated to continually suppress these pests below economically damaging levels throughout the growing season in these farmscapes. Technical Abstract: In peanut-cotton farmscapes in Georgia, stink bugs, i.e., Nezara viridula (L.), Euschistus servus (Say), and Chinavia hilaris (Say), develop in peanut and then disperse at the crop-to-crop interface to feed on fruit in cotton. The main objective of this study was to examine the influence of a habitat of tropical milkweed (Asclepias curassavica L.) on biological control of stink bugs in cotton bordered by peanut. Pest density and parasitism rates were monitored in replicated cotton plots (22.9 ' 14.6 m) with or without milkweed habitats in 2009 and 2010. For the insectary habitat, 25 potted flowering milkweed plants were placed 1.2 m apart along the edge of a cotton plot. The milkweed habitat increased host parasitism by Trichopoda pennipes (F.) both years. These treatment differences were not due to differences in host density. Parasitism of E. servus by Cylindromyia spp. was similar between treatments in 2010. In the first year of the study, stink bug damage (15.6%) reached economic threshold in control cotton on week 3, two weeks before stink bug damage (31.3%) was at economic threshold level in milkweed cotton. In 2010, stink bug damage reached economic threshold on week 3 in both control cotton (23%) and milkweed cotton (24%). In conclusion, provision of a milkweed habitat at the crop-to-crop interface increased host parasitism by T. pennipes in cotton. In the first year of the study, there was some indication that this sole management strategy can help keep stink bugs below economic threshold in this crop. Complimentary management strategies, though, may also need to be incorporated to continually suppress these pests below economically damaging levels throughout the growing season in these farmscapes. |