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ARS Home » Pacific West Area » Parlier, California » San Joaquin Valley Agricultural Sciences Center » Commodity Protection and Quality Research » Research » Publications at this Location » Publication #398832

Research Project: Improved Systems-based Approaches that Maintain Commodity Quality and Control of Arthropod Pests Important to U.S. Agricultural Production, Trade and Quarantine

Location: Commodity Protection and Quality Research

Title: Season-long comparison of trap lures for integrated management of the navel orangeworm (Lepidoptera: Pyralidae) in almond and pistachio

item Siegel, Joel
item Burks, Charles - Chuck

Submitted to: CABI Agriculture and Bioscience (CABI A&B)
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/14/2024
Publication Date: 3/25/2024
Citation: Siegel, J.P., Burks, C.S., Wilson, H. 2024. Season-long comparison of trap lures for integrated management of the navel orangeworm (Lepidoptera: Pyralidae) in almond and pistachio. CABI Agriculture and Bioscience (CABI A&B). 5. Article 30.

Interpretive Summary: The navel orangeworm (NOW) is a moth species that is the principal pest of California almonds and pistachios, crops worth over $8 billion dollars annually in unprocessed form and produced on over 1.5 million acres of land in California. Monitoring to improve judicious use of insecticides is an important ongoing research topic in sustainable production of these economically important crops. We used monitoring data from a demonstration project, collected from 468 traps on 6.5 square miles of commercial almond and walnut orchards weekly over a 3-year period, to compare trapping data in almonds and walnuts between traps baited with attractants primarily for females vs. an attractant that traps both sexes. Under most circumstances the traps baited with the bisexual attractant captured more NOW than the female attractant, but in pistachios in spring both attractants were approximately equally effective. The data revealed year-to-year variation in the onset of spring activity of NOW, and indicated that these data are regionally consistent within a year. These findings show potential value for data provided publicly in real time from intense regional monitoring sites for NOW.

Technical Abstract: The navel orangeworm Amyelois transitella (Walker) (Lepidoptera: Pyralidae) is the principal insect pest of almond and pistachio. Monitoring for navel orangeworm is complicated by the widespread use of mating disruption. Monitoring methods that are minimally affected by mating disruption include the use of natural ovipositional substrates (ovibait) to attract gravid females, and phenyl propionate (PPO), a volatile chemical that attracts both sexes. In this study we compared data from these attractants obtained from a demonstration project for sterile insect technique. Trapping stations were maintained at a rate of one per 7.19 four almond orchards and four pistachio orchards, each 65 to 259 ha. Each trapping stations had a one sticky trap baited with ovibait and one sticky trap baited with PPO synergized with a pheromone monitoring lure (PPO-pheromone). In spring in pistachio orchards, ovibait traps captured as many adults as phenyl propionate, while PPO-pheromone traps captured far more adults than ovibait later in the year in pistachios and at all times of the year in almonds. The monitoring data from both attractants indicated that year-to-year variability in the onset of activity was consistent between crops and across the region. The proportion of males captured with both trapping methods was greater early in the spring and later in the fall. These data indicate potential utility of regional monitoring sites publicly providing real-time trapping data.