Project Number: 5302-43000-034-02
Project Type: Trust

Start Date: Jan 01, 2004
End Date: Dec 31, 2008

Objective:
Setup and evaluate field trials of commercial nematode products for postharvest control of navel orangeworm in pistachio orchards. Evaluate efficacy of current sanitation methods.

Approach:
Insect-pathogenic nematodes (EPN) have symbiotic relationships with bacteria that can kill host insects rapidly (within 48 h) and are biological control agents with a demonstrated ability to attack a range of pest species in cryptic habitats (Kaya and Stock, 1997). In our first year study, we demonstrated that Steinernema carpocapsae can produce > 75% mortality in NOW larvae infesting pistachios and that soil temperatures below freezing and above 87° F are deleterious to nematode efficacy. The nematode concentrations used in our small-plot studies were 10 and 5 infective juveniles (IJs)/cm2 applied in 374 ml or 500 ml water per plot (400 gal/ac, 530 gal/ac) followed by wetting at the same rate (Siegel et al., 2004). The nematodes were provided by Certis USA and were fermented in their plant in Wasco, Ca. Studies conducted in 2004 investigated the feasibility of using lower application rates of water (200 gal/ac-186 ml per plot) as well as refining the window of opportunity for using nematodes. The nematodes in these studies, although provided by Certis USA, were produced by Becker Underwood and were formulated as a gel. Documents Trust with CA Pistachio Commission. Log 25896. Formerly 5302-43000-031-09T (6/2008)