Short-term physiological response of a native Hawaiian plant, Hibiscus arnottianus, to injury by the exotic leafhopper, Sophonia orientalis (Hemiptera: Cicadellidae)

Authors: AVANESYAN, ALINA - Botanical Society Of America; SNOOK, KIRSTEN - US Department Of Agriculture (USDA); Follett, Peter; LAMP, WILLIAM - University Of Maryland

Submitted to: Environmental Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/3/2018
Publication Date: 4/1/2019
Citation: Avanesyan, A., Snook, K., Follett, P.A., Lamp, W. 2019. Short-term physiological response of a native Hawaiian plant, Hibiscus arnottianus, to injury by the exotic leafhopper, Sophonia orientalis (Hemiptera: Cicadellidae). Environmental Entomology. 48(2):363-369. https://doi.org/10.1093/ee/nvy193.
DOI: https://doi.org/10.1093/ee/nvy193

Interpretive Summary: The two-spotted leafhopper, Sophonia orientalis(Matsumura)(Hemiptera: Cicadellidae) is an exotic pest of several economically important crop and endemic plants in Hawaii. We examined the short-term physiological response of a native Hawaiian plant, Hibiscus arnottianus(A.Gray), and Camellia sinensis(L.)Kuntze, a host plant of S.orientalis in its native Asia, to injury by S.orientalis. We found that H.arnottianus plants demonstrated a rapid physiological response to injury accompanied by 40% reduction in rate of photosynthesis and 42% reduction in rate of transpiration, whereas C.sinensis did not exhibit any reduction in gas exchange rates. Our results suggest that H.arnottianus is responding to leafhopper feeding with a generalized wound response predicted for novel plant-insect herbivore ssociations. We discuss potential future directions for studies which might focus on host plant responses to S.orientalis in its native versus introduced range.

Technical Abstract: The two-spotted leafhopper, Sophonia orientalis(Matsumura)(Hemiptera: Cicadellidae) is a widespread exotic pest of many economically important crop plants and ornamental plants in Hawaii. Sophonia orientalis is highly polyphagous and is a major threat to some of the native endemic plants. Despite the successful establishment in Hawaii, interactions of S.orientalis with its host plants remain poorly understood. Previous studies primarily focused on distribution, parasitism, and oviposition of S.orientalis in Hawaii; whereas plant physiological responses to the leafhopper injury, and specifically, gas exchange rates in plants, have not been described yet. In this study we examined a short-term physiological response of a native Hawaiian plant,Hibiscus arnottianus (A. Gray) to injury by S.orientalis. We also explored whether Camellia sinensis (L.) Kuntze, a native host plant of S.orientalis in Asia, exhibits a similar response. We found that H.arnottianus plants demonstrated a rapid physiological response to injury accompanied by 40% reduction in rate of photosynthesis and 42% reduction in rate of transpiration, whereas C.sinensis did not exhibit any reduction in gas exchange rates. We did not record any changes in plant chlorophyll levels after plant injury in both Hibiscus and Camellia plants. Our results suggest that H.arnottianus plant is responding to the leafhopper feeding with a generalized wound response predicted for novel plant-insect herbivore associations. We discuss potential future directions for studies which might focus on host plant responses to S.orientalis in its native versus introduced range.