Location: Fruit and Nut ResearchTitle: Laboratory virulence of entomopathogenic nematodes to two ornamental plant pests, Corythucha ciliata (Hemiptera: Tingidae) and Stethobaris nemesis (Coleoptera: Curculionidae) Author
|Shapiro Ilan, David|
Submitted to: Florida Entomologist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/27/2012
Publication Date: 12/31/2012
Citation: Shapiro Ilan, D.I., Mizell III, R.F. 2012. Laboratory virulence of entomopathogenic nematodes to two ornamental plant pests, Corythucha ciliata (Hemiptera: Tingidae) and Stethobaris nemesis (Coleoptera: Curculionidae). Florida Entomologist. 95:922-927. Interpretive Summary: Insect pests of ornamental plants can cause severe damage to commercial production, plant health, and aesthetic value. Research and development of environmentally friendly pest control measures to control ornamental plant pests is warranted. In this study, we evaluated the potential of beneficial nematodes to control two important ornamental pests: 1) the sycamore lace bug and 2) the recently described amaryllis weevil (named Stethobaris nemesis). Beneficial nematodes (also called entomopathogenic nematodes) are environmentally friendly bio-insecticides; unlike plant parasitic nematodes, these beneficial nematodes only attack insects. After testing a number of different nematode strains and species in the laboratory, we discovered that a nematode named Heterorhabditis indica appears most promising for control of the sycamore lace bug, and a nematode named Steinernema carpocapsae appears most promising for control of the amaryllis weevil. Additional experiments are needed to expand upon this research and determine the ability of these nematodes to kill the target pests under field conditions.
Technical Abstract: In this study we evaluated the potential of entomopathogenic nematodes to control two important ornamental pests: 1) Corythucha ciliata, a native lace bug that attacks the foliage of sycamore trees, and 2) the recently described exotic pest, Stethobaris nemesis, a weevil that attacks amaryllis leaves and bulbs. In the laboratory, the virulence of six entomopathogenic nematode strains was evaluated for potential to control C. ciliata, and four nematode species were evaluated for S. nemesis. Heterorhabditis indica (HOM1) exhibited higher virulence to C. ciliata than H. bacteriophora (Baine and Oswego strains), H. georgiana (Kesha), and Steinernema riobrave (355); S. carpocapsae (All) virulence was considered the second highest (after H. indica). Additionally, H. indica (HOM1) caused the highest level of reproduction in C. ciliata. Steinernema carpocapsae (All) exhibited the highest virulence to control S. nemesis, yet both S. carpocapsae (All) and S. feltiae (SN) exhibited high virulence after only 1d post-treatment. The other nematodes tested for S. nemesis suppression, H. bacteriophora (Hb) and H. indica (HOM1), also showed high levels of virulence particularly 3 d post-treatment. Our results indicate that several entomopathogenic nematodes offer potential for control of C. ciliata and S. nemesis and thus additional research, e.g., field studies, is warranted.