Nitric oxide fumigation for control of navel orange worm Amyelois tronsitella on walnut

Authors: YANG, XIANGBING - University Of California; Liu, Yong Biao

Submitted to: Entomological Society of America Annual Meeting
Publication Type: Proceedings
Publication Acceptance Date: 9/12/2019
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: The navel orange worm, Amyelois tronsitella (Walker), is a major insect pest of nut products, e.g., walnut, almonds, and pistachios. Infestation by A. tronsitella starts in the field and continues through harvest and storage. Nitric oxide (NO) was recently discovered as an effective fumigant against various insect pests of fresh and stored products and, therefore, has potential to control A. tronsitella on stored nut products. In this study, we evaluated efficacy of NO fumigation against A. tronsitella at different life stages on walnut at 25°C under ultralow oxygen conditions (< 35 ppm O2). When A. tronsitella on artificial diet was fumigated, complete control of eggs was achieved in 16 and 8 h at 2.0 and 3.0% NO, respectively; small and large larvae were controlled in 16, 8, and 4 h at 0.5, 1.0, and 2.0% NO, respectively; and pupae were controlled in 24, 16, and 8 h at 0.5, 1.0, and 2.0% NO, respectively. In unshelled walnuts, complete control of small larvae was achieved in 16, 8, and 6 h at 0.5, 1.0, and 1.5% NO, respectively; large larvae were completely controlled in 24, 8, and 4 h at 0.5, 1.0, and 2.0% NO, respectively; pupae were completely controlled in 24, 16, and 8 h at 0.5, 1.0, and 2.0% NO, respectively. NO fumigation is efficacious against A. tronsitella at all life stages on walnut, and should be further investigated as a commercial alternative to methyl bromide for postharvest pest control.