Fitness and survival of Helicoverpa zea (Lepidoptera: Noctuidae) on five weedy host plants commonly found across the Mid-South

Authors: Glover, James; Reddy, Gadi V.P.; Portilla, Maribel

Submitted to: Florida Entomologist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/27/2022
Publication Date: 4/18/2023
Citation: Glover, J.P., Reddy, G.V., Portilla, M. 2023. Fitness and survival of Helicoverpa zea (Lepidoptera: Noctuidae) on five weedy host plants commonly found across the Mid-South. Florida Entomologist. 106(1):45-50. https://doi.org/10.1653/024.106.0107.
DOI: https://doi.org/10.1653/024.106.0107

Interpretive Summary: The cotton bollworm, Helicoverpa zea, is a cosmopolitan and highly polyphagous pest that feeds on numerous wild and cultivated crops. Bollworms are significant economic pests of southern row crops including cotton, corn, and soybean. Previous work has shown host plants can have significant effects on insect development, reproductive capability, and survivorship for many noctuids species. Here we investigate the effects of five commonly encountered host plants on the overall suitability and potential impact to local populations of cotton bollworm. Insects were reared individually on each of the non-cultivated host plants and allowed to develop to adult hood and mate. The average developmental time for cotton bollworm ranged from 30.3 to 39.6 days develop to adulthood when reared on honeysuckle and white clover. Overall, the results suggest mortality, emergence, and average number of eggs was significant influenced by weedy host but were greatest when were reared on kudzu. Crimson clover and white clover were among the most suitable hosts as measured by the average number of eggs laid. These data have implications that may aid in refining current integrated pest management and chemical control strategies in agroecosystems impacted by cotton bollworm.

Technical Abstract: The objective of this study was to compare demographic parameters of Helicoverpa zea L. (Boddie) (Lepidoptera: Noctuidae) on five weedy host plants common across the Mid-south: crimson clover (Trifolium incarnatum L.), white clover (Trifolium repens L.), hairy vetch (Vicia villosa Roth), honeysuckle (Lonicera japonica), and kudzu (Pueraria montana) evaluated under laboratory condition s at 25' ± 2 °C and a relative humidity of 50 ± 10% and photoperiod L:D = 14:10. Egg, larval, and pupal developmental times, pupal weight, longevity, and fecundity of H. zea were measured. Larvae of H. zea successfully developed on all five host plants to adulthood, however significant mortality > 50% was observed for larvae reared on hairy vetch, honeysuckle, and kudzu. Laravel developmental periods ranged from 30.2 d to 39.6 d for H. zea reared on honeysuckle and white clover respectively. Pupal biomass ranged from 217.4 mg for females reared on white clover and 213.6 mg for males on honeysuckle to 161.2 and 158.1 for female and males reared on hairy vetch. Pupal emergence varied from 92.1 % to 61.8 % for crimson clover and hairy vetch, respectively. Larval mortality varied from 27.4% on crimson clover to 66.4% for hairy vetch. Average adult longevity ranged from 10.3 d to 11.2 d for female s and males reared on crimson clover to 4.4 d on kudzu and 4.6 d on white clover for female and male, respectively. The average number of eggs oviposited by females reared on crimson clover, white clover, hairy vetch, honeysuckle, and kudzu were 553.5, 512.3, 288.2, 194.7, and 142.2, respectively. Our findings indicate crimson and white clover were among the most suitable hosts, and kudzu the most resistant based on larval mortality and reproductive capability.