Mass rearing and augmentative biological control evaluation of Rhynocoris fuscipes (Hemiptera: Reduviidae) against multiple pests of cotton

Authors: THOMSON, MAJESH - Pest Control, Ltd; SAHAVARAJ, KITHERIAN - Pest Control, Ltd; KUMAR, VIVEK - University Of Florida; AVERY, PASCO - University Of Florida; McKenzie, Cindy; OSBORNE, LANCE - University Of Florida

Submitted to: Pest Management Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/20/2017
Publication Date: 7/3/2017
Citation: Thomson, M., Sahavaraj, K., Kumar, V., Avery, P.B., McKenzie, C.L., Osborne, L.S. 2017. Mass rearing and augmentative biological control evaluation of Rhynocoris fuscipes (Hemiptera: Reduviidae) against multiple pests of cotton. Pest Management Science. 73(8):1743-1752.

Interpretive Summary: Reduviids are insect predators well known for their biological control potential against insect pests of field crops. We developed a method for the mass production of a generalist reduviid predator Rhynocoris fuscipes (R. fuscipes) and evaluated this predator’s efficacy against insect pests of cotton. In addition, the economics of using this predator against insect pests of cotton were assessed. Adults showed higher prey consumption than younger stages. In a field study, R. fuscipes significantly suppressed multiple pests of cotton. Although the cost benefit ratio and percent avoidable loss was higher in fields sprayed with chemical pesticides compared to plots where R. fuscipes was released, significantly higher crop yield and cost benefit ratio was observed in R. fuscipes plots than the control plots. Our results provide additional and supportive evidence to the available information on the suitability of reduviid predators for sustainable management of various arthropod pests of agricultural importance.

Technical Abstract: Rhynocoris fuscipes (Fab.) (Hemiptera: Reduviidae) is a generalist predator of cotton pests and is commonly found inhabiting cotton growing regions in southern India. With the goal to integrate this predator in standard management practices used against cotton pests on a commercial scale, 1) we developed a protocol for adult group rearing of this predator inside Micro Environmental Cages (MECs), and 2) evaluated the biocontrol potential of mass produced predators against cotton pests under potted and field conditions. Higher fecundity and adult longevity of Rhynocoris fuscipes (R. fuscipes) was recorded in the MECs than under natural growing conditions. The reduviid predator preferred stones and fallen leaves as their hiding places in the MECs. During the morning hours, the predator showed a higher biocontrol potential against Phenacoccus solenopsis Tinsley (2.8 prey / predator) compared to Dysdercus cingulatus (Fab.) (1.5 prey / predator) under potted conditions. Under field conditions, R. fuscipes significantly reduced the population of Aphis gossypii Glover, P. solenopsis, D. cingulatus and Helicoverpa armigera (Hübner) by 28 percent, 70 percent, 29 percent and 50 percent, respectively. No negative impact of R. fuscipes was reported on other natural enemies existing in the cotton agroecosystem. Significantly higher crop yield and cost benefit ratio was observed in R. fuscipes released plots than the control plots. The results suggest that R. fuscipes can efficiently be mass produced under controlled conditions in MECs, and used in an integrated management program for multiple cotton pests.