ARS | Publication request: Ambient almond volatiles from geographically different orchards and their relationship to navel orangeworm

Submitted to: Entomological Society of America Annual Meeting
Publication Type: Proceedings
Publication Acceptance Date: March 14, 2009
Publication Date: N/A

Interpretive Summary: Several studies have investigated the various non-volatile and volatile components of various plant parts; however, the volatile organic compound (VOC) emission of several cultivars in an almond orchard has not been studied. This aspect is particularly relevant to research concerning the navel orangeworm (NOW), a major insect pest of almonds and other tree nuts. Feeding damage by NOW lowers nut kernel quality resulting in considerable monetary loss to growers, producers, and shippers; thus, control of NOW is one of the top priorities of the California tree nut industry. Despite several flights of NOW, the identification of background VOCs, or their potential correlation to NOW attractancy, has not been addressed. The ambient VOC emission of two almond orchards was collected during the months of May-July via a large-scale volatile collection system developed specifically for tree-nut orchards. The collected VOCs were indivdually subjected to electroantennographic (EAG) bioassy; several VOCs exhibited positive EAG signals from both male and female NOW moths. Synthetic blends mimicing the natural ambient VOC makeup were formulated and evaluated for efficacy as background bouquet VOC mixes for use as adjuvants for NOW attractants, or as a background adjuvant for use with lab-based research bioassays with NOW such as EAG or flight tunnel experiments.

Technical Abstract: Several studies have investigated the various non-volatile and volatile components of various plant parts; however, the volatile organic compound (VOC) emission of several cultivars in an almond orchard has not been studied. This aspect is particularly relevant to research concerning the navel orangeworm (NOW), a major insect pest of almonds and other tree nuts. Despite several flights of NOW, the identification of background VOCs, or their potential correlation to NOW attractancy, has not been addressed. The ambient VOC emission of two almond orchards was collected during the months of May-July via a large-scale volatile collection system developed specifically for tree-nut orchards. The collected VOCs were indivdually subjected to electroantennographic (EAG) bioassy; several VOCs exhibited positive EAG signals from both male and female NOW moths. Synthetic blends mimicing the natural ambient VOC makeup were formulated and evaluated for efficacy as background VOC mixes for NOW attractants.