Predation potential of Rhynocoris marginatus (Hemiptera: Reduviidae) against three mealybug species of agricultural importance

Authors: SAHAVARAJ, KITHERIAN - Central Agricultural University; KUMAR, VIVEK - University Of Florida; BANU, NAZEERA - Central Agricultural University; AVERY, PASCO - University Of Florida; RADHIKA, AUBU - Central Agricultural University; McKenzie, Cindy; OSBORNE, LANCE - University Of Florida

Submitted to: Applied Entomology and Zoology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/9/2018
Publication Date: 8/2/2018
Citation: Sahavaraj, K., Kumar, V., Banu, N., Avery, P., Radhika, A., McKenzie, C., Osborne, L. 2018. Predation potential of Rhynocoris marginatus (Hemiptera: Reduviidae) against three mealybug species of agricultural importance. Applied Entomology and Zoology. https://doi.org/10.1007/s13355-018-0576-6.
DOI: https://doi.org/10.1007/s13355-018-0576-6

Interpretive Summary: Reduviids are well known for their biological control potential against multiple pests attacking field crops. In the current study, we evaluated the predation potential and prey species preference of a generalist reduviid predator Rhynocoris marginatus among three important mealybug pests of cotton, Phenacoccus solenopsis, Maconellicoccus hirsutus and Coccidohystrix insolita, under the controlled laboratory conditions. Among the three prey developmental stages (second and third nymphal instars, and adult) tested for each mealybug species, the adult stage was found to be the most preferred stage for predation by all developmental stages of R. marginatus. The adult stage of R. marginatus was found to be the most voracious feeder resulting in a significantly high mortality of mealybugs. When the three mealybug species offered together, R. marginatus preferred P. solenopsis the most, followed by M. hirsutus and C. insolita. Results obtained from the current study, suggest that the R. marginatus can be a promising tool for the management of different mealybug pests infesting cotton production.

Technical Abstract: The predation potential of a generalist predator Rhynocoris marginatus (Fab.) (Hemiptera: Reduviidae) was evaluated against three important mealybug pests of cotton, Phenacoccus solenopsis Tinsley, Maconellicoccus hirsutus Green and Coccidohystrix insolita Green (Hemiptera: Pseudococcidae) under laboratory conditions. The specific objective of the study was to determine the prey-capturing time, prey handling time and prey preference among three mealybug species by different developmental stages of R. marginatus. The number of prey consumed/predator/24 hrs by R. marginatus was affected by developmental stage. Rhynocoris marginatus showed a decrease in prey capturing time and handling times as grew older. After evaluation of the prey stage preference, results indicated that developmental stages of R. marginatus, preferred adult mealybugs over the younger stages. In the choice-test bioassay among three mealybug species, irrespective of developmental stages, R. marginatus preferred P. solenopsis the most, followed by M. hirsutus and C. insolita. This supports the idea that R. marginatus can be effectively utilized for the management of one of the most destructive mealybug pests of cotton, P. solenopsis. Results from this study are important for the development of a knowledge-based management program in cotton agroecosystems affected by various mealybug pests.