Quality Assessment of Shipments of the Parasitoid Eretmocerus eremicus (Hymenoptera: Aphelinidae) Received from Two Biological Control Suppliers

Abstract

Quality assessments of commercially available biological control (BC) agents is important to ensure the success of a BC program. It is important that greenhouse producers assess if BC agents received from BC suppliers are alive and functional before releasing into greenhouse production systems. We conducted a preliminary study to determine the quality of shipments from two suppliers of the whitefly parasitoid, Eretmocerus eremicus Rose & Zolnerowich (Hymenoptera: Aphelinidae). Release cards containing parasitized pupae of the sweetpotato whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), were individually placed into 500 mL Mason jars and a 4 x 5 cm yellow sticky card was attached to the inner lids. We found differences between the two shipments received from the two suppliers. For the first shipment, supplier B had a higher mean number of adults captured on the yellow sticky cards than supplier A (Laboratory: 10.1 versus 4.2 and Distributor: 19.1 versus 5.9 adults, respectively). However, for the second shipment, supplier A had a higher mean number of adults captured on the yellow sticky cards than supplier B (Laboratory: 14.5 versus 8.1 and Distributor: 20.9 versus 8.0 adults, respectively). Our preliminary study shows that formulations (release cards) of BC agents and emergence of adults can vary depending on individual shipments from the supplier providing the BC agents. Therefore, greenhouse producers should develop protocols for quality assessments of purchased BC agents before releasing them into greenhouses to ensure they have the best chance of successfully regulating pest populations below damaging levels.