Page Banner

United States Department of Agriculture

Agricultural Research Service

Research Project: ECOLOGICALLY-BASED PEST MANAGEMENT STRATEGIES FOR WESTERN COTTON Title: Employing immunomarkers to track dispersal and trophic relationships of piercing-sucking predator, Podisus maculiventris (Hemiptera: Pentatomidae)

Authors
item Kelly, Jessica -
item Hagler, James
item Kaplan, Ian -

Submitted to: Environmental Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 20, 2012
Publication Date: December 31, 2012
Citation: Kelly, J.L., Hagler, J.R., Kaplan, I. 2012. Employing immunomarkers to track dispersal and trophic relationships of piercing-sucking predator, Podisus maculiventris (Hemiptera: Pentatomidae). Environmental Entomology. 41(6):1527-1533.

Interpretive Summary: Proteins such as rabbit IgG and chicken IgY are easy to apply and analyze on insects for monitoring dispersal and/or pest consumption, but current application techniques are less effective in research for the large guild of piercing-sucking predators used in biocontrol. In this study we quantified the potential of using protein immunomarks as a tool in tracking dispersal of a piercing-sucking predator, the spined soldier bug, and its predation on the hornworm caterpillar. An external rabbit IgG mark was topically applied to the predator to assess persistence under field conditions. Internal marks were then incorporated into the artificial diet of the caterpillar (prey) to test the retention of the internal mark. Finally, the lateral transfer of the internal mark into the predator after feeding on marked prey was assessed. We also tested four factors which are likely to affect the success of this technique: (i) mark type (rabbit IgG vs. chicken IgY); (ii) protein concentration in diet; (iii) time that caterpillar prey were reared on protein enriched diet; and (iv) time off protein enriched diet. External marks remained detectable on 100% of the predators after three days and >50% still tested positive 12 days after application in the field, thus suggesting that it will be an effective mark for dispersal studies. Internal diet-based marking was also effective in tracking feeding by the predator on the marked prey, especially when using rabbit IgG. Nearly 90% of the stink bugs that were fed a caterpillar previously reared on IgG-enriched diet retained their mark for 24 hours. Surprisingly, diet concentration and time reared on diet had comparatively little impact on mark retention for IgG or IgY. These protocols will be used in the future to monitor the dispersal and prey consumption of stink bugs in the agroecosystem.

Technical Abstract: Proteins such as rabbit IgG and chicken IgY are markers that are easy to apply and analyze on insects for monitoring dispersal and/or pest consumption, but current application techniques are less effective in research for the large guild of piercing-sucking predators used in biocontrol. To address this problem, we quantified the potential of using protein immunomarks as a tool in tracking emigration of the spined soldier bug, Podisus maculiventris (Say) (Hemiptera: Pentatomidae) and predation on the hornworm caterpillar, Manduca sexta (L.) (Lepidoptera: Sphingidae). An external rabbit IgG mark was topically applied to adult P. maculiventris to assess persistence under field conditions for >2 weeks. Internal marks were incorporated into the artificial diet of M. sexta to test the retention of the internal mark in the prey and then the lateral transfer of the mark into a consumer of the prey. We also manipulated the following four factors, all of which are likely to affect the success of this technique: (i) mark type (rabbit IgG vs. chicken IgY); (ii) protein concentration in diet (0.5 vs. 1.5 mg/ml); (iii) time that caterpillars were reared on protein enriched diet (1, 2, 3 days); and (iv) time off protein enriched diet developing on unmarked tomato leaves (0, 1, 2, 3, 5, 7 days). External marks remained detectable in 100% of individuals after three days and >50% still tested positive 12 days after application in the field. Internal diet-based marking was also effective in tracking feeding by P. maculiventris on M. sexta, especially using rabbit IgG which was far more persistent than chicken IgY. Nearly 90% of stink bugs fed caterpillars previously reared on IgG-enriched diet retained their mark for 24 hours. Surprisingly, diet concentration and time reared on diet had comparatively little impact on mark retention for IgG or IgY. Development on unmarked tomato leaves clearly diluted the initial diet mark, but plant-reared individuals that were marked with IgG and IgY were still successfully detected in 35% and 20% of the predators, respectively. In future field experiments, we intend on using this protocol to simultaneously monitor the emigration and prey consumption of P. maculiventris in augmentation biocontrol of crop pests.

Last Modified: 11/23/2014
Footer Content Back to Top of Page