Susceptibility of yellow squash and zucchini cultivars to the sweetpotato whitefly, Bemisia tabaci Gennadius (MEAM1) in the southeastern United States

Authors: MBATA, GEORGE - Fort Valley State University; LI, YINPING - Fort Valley State University; WARSI, SANOWER - Fort Valley State University; Simmons, Alvin

Submitted to: Insects
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/4/2024
Publication Date: 6/6/2024
Citation: Mbata, G.N., Li, Y., Warsi, S., Simmons, A.M. 2024. Susceptibility of yellow squash and zucchini cultivars to the sweetpotato whitefly, Bemisia tabaci Gennadius (MEAM1) in the southeastern United States. Insects. 15, 429. https://doi.org/10.3390/insects15060429.
DOI: https://doi.org/10.3390/insects15060429

Interpretive Summary: The sweetpotato whitefly is a major pest of vegetable crops. We evaluated the susceptibility of 20 yellow squash and zucchini across three growing seasons in the southeastern United States. The zucchini cultivar 'Gentry' harbored the most adults, while 'Caserta' was the least attractive zucchini cultivar to the adult whiteflies. For yellow squash, 'Early Summer' and 'Amberpic 8455' were the cultivars with the highest adult populations, while cultivar 'Golden Goose Hybrid' harbored the lowest number of adult whiteflies. For the yellow squash cultivars, 'Gourmet Gold Hybrid,' 'Black Beauty,' and 'Early Prolific' harbored the highest yield. For zucchini, 'Respect,' 'Sure Thing Hybrid,' and 'Green Eclipse Zucchini' were the top performers in yield, with 'Respect' consistently had the highest yield across the seasons. These results provide valuable information for the agricultural community concerning yellow squash and zucchini squash production while being challenged by attack from whiteflies.

Technical Abstract: The sweetpotato whitefly, Bemisia tabaci (Gennadius) Middle East-Asia Minor 1 (MEAM1), causes significant losses to vegetable crops directly by sap-feeding, inducing plant physiological disorders, promoting the growth of sooty mold, and indirectly by transmitting plant viruses. In this study, we evaluated the susceptibility of 20 yellow squash and zucchini (Cucurbita pepo) cultivars to MEAM1, across three growing seasons in the southeastern United States. Weekly sampling of the numbers of MEAM1 adults, nymphs, and eggs were conducted from the third week after seed sowing and across 6 weeks during the summer and fall of 2021 and fall of 2022. In general, adult whitefly populations were high during the first week of sampling, but decreased as the seasons progressed. The zucchini cultivar 'Gentry' harbored the most adults, while 'Caserta' was the least attractive zucchini cultivar to the adults. For yellow squash, 'Early Summer' and 'Amberpic 8455' were the cultivars with the highest adult populations, while 'Golden Goose Hybrid' harbored the lowest adult count. Whitefly egg counts across both squashes trailed those of adults and in the second week of sampling. The counts of nymph increased as the seasons progressed, but there was a decline after the second week during fall 2021. For yellow squash cultivars, 'Gourmet Gold Hybrid,' 'Black Beauty,' and 'Early Prolific' recorded the highest yield. For zucchini, 'Respect,' 'Sure Thing Hybrid,' and 'Green Eclipse Zucchini' were the top performers in yield, with 'Respect' consistently achieving the highest yield across the seasons. These results provided valuable information for whitefly management on yellow squash and zucchini based on host plant susceptibility and yield.