Alternative Methods to Manage Silverleaf Whitefly [Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae)] in Zucchini (Cucurbita pepo L.)

Whiteflies are the most detrimental insect pest for cucurbit crops in Georgia, USA. Plant growth and yield are severely reduced due to whitefly feeding and, more importantly, many plant viruses they vector. Chemical management of whiteflies has been ineffective. An integrated pest management (IPM) strategy is needed to reduce whitefly numbers to an acceptable level in cucurbit crops in Georgia. This study evaluated the impact of plastic mulch color, exclusionary row covers, particle clay, and organic insecticidal solutions (soap and neem oil) on plant growth, fruit yield, and whitefly index (WFindex) in zucchini squash (Cucurbita pepo L). The study was conducted during the fall of 2019 and 2020. Particle clay applications reduced zucchini foliar temperatures and WFindex and increased zucchini fruit yields. Black plastic mulch reduced fruit yield due to increased root zone temperature and did not impact whitefly numbers. Neem oil and soap decreased the WFindex but inconsistently affected fruit yield and quality. Our findings indicate that neem oil, soap, and particle clay may be part of an IPM program for whiteflies. However, further evaluations are needed in large plots and commercial fields to confirm the preliminary results of this study.