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United States Department of Agriculture

Agricultural Research Service

Research Project: AN AREAWIDE CONTROL PROGRAM FOR NAVEL ORANGEWORM

Location: Commodity Protection and Quality

2009 Annual Report


1a.Objectives (from AD-416)
1. Implement an area-wide IPM program that will reduce navel orangeworm damage, aflatoxin contamination, and broad-spectrum insecticide use throughout the Central Valley. 2. Collect baseline data characterizing the experimental plots in terms of NOW population density, historic levels of damage, sanitation efficacy, and the cost of current practices. Compare the efficacy of current and proposed NOW management programs using cost/benefit analysis. 3. Identify key variables responsible for both consistent control and program failure and analyze the relative importance of these variables using epidemiological/epizootiological statistics. 4. Expand an existing damage prediction model for Nonpareil almond damage that is based on Kern County data, to the other growing regions in the Central Valley; and develop a damage prediction model for pollenizer varieties of almonds and validate the model in the different growing regions. 5. Determine the role played by NOW movement among multiple hosts on the efficacy of the new management practices demonstrated. 6. Create NOW damage databases using grower-provided data that can identify high-risk areas for each commodity within a county and utilize these databases to develop a better understanding of the distribution of both NOW infestation and aflatoxin contamination within and between counties. 7. Work with farm advisers and an advisory council to develop educational programs and training materials to instruct growers on the strategies demonstrated in the area-wide proposal.


1b.Approach (from AD-416)
Establish and implement an areawide pest management research and action program for navel orangeworm management which (a) results from a stakeholder partnership and collaboration dedicated to the demonstration and areawide adoption of navel orangeworm control technologies; (b) demonstrates the positive impacts and advantages of such a program through enhanced grower profits, reduced worker risks, an enhanced environment, and a proven superiority of area-wide adoption; and (c) achieves a mature navel orangeworm management system so end-users, consultants and other interested parties will be left with an operation program that will meet the overall goals through its wide-scale adoption. This will require the development of a unified effort between Federal, State, local and private interests, and whose participants will be involved in the program from conception to adoption.


3.Progress Report
In the Sacramento Valley, mating disruption dispensed by aerosol puffers in walnuts was evaluated at sites selected in cooperation with 14 growers and their Pest Control Advisers, covering more than 2,000 acres. This new technology will be expanded to 10,000 acres in the coming year. In the San Joaquin Valley, a mating disruption demonstration site comprising 2,400 acres of almonds was established in cooperation with three growers and four Pest Control Advisors. Baseline NOW and beneficial insect population data were collected for the 2008 crop season, so that that the efficacy of mating disruption employing aerosol puffers could be demonstrated in 2009. At the longest running mating disruption site in almonds (5,000 acres) in Kern County, evaluation is continuing and a Field Day demonstrating this technology to growers and pest control advisers was held in July. Scientists continued to gather data on the rate of development and pattern of emergence of NOW in almonds and pistachios in the San Joaquin Valley in order to increase the precision of insecticide treatments employing new narrow spectrum insecticides, which will facilitate the adoption of mating disruption once population levels are reduced. Additional studies quantified insecticide coverage and established the duration of commodity protection, which will aid farm advisors in making recommendations to growers, which in turn will allow growers to choose chemicals that best fit their management practices. Information on the prevalence of aflatoxin-producing molds on adult NOW was obtained, and the study of their possible role in dispersing aflatoxin-producing molds was initiated. This information will be incorporated with the existing data on physical damage caused by NOW in order to refine the current methods of the economic assessment of control costs. Supporting studies in both the Sacramento and San Joaquin Valleys monitored NOW survival in unharvested almonds, pistachios and walnuts over the winter in order validate the more more stringent sanitation standards proposed by this project for improved control of NOW. A simple spreadsheet educational tool enabling growers to predict damage based on their current practices was developed and will be distributed by the UCCE farm advisors.

Cooperator activity was monitored by means of a stakeholder meeting, September 2008, oral presentations to growers and pest control advisers on the relationship between pistachio phenology and damage on Statewide Pistachio Day, January, 2009, and an overview of the areawide program was presented to growers, farm advisors, and pest control advisers at the annual meeting of the Almond Board of California, December 2008. Additional information to UCCE farm advisors was provided by meetings, telephone calls and e-mail.


4.Accomplishments
1. Mating Disruption Using Sex Pheromone for Control of Navel Orangeworm in Almonds. Currently, insecticides and sanitation are the only methods used to control navel orangeworm, the primary pest of almonds in California, supplier of 79% of all almonds in the world. A demonstration site comprising more than 2,000 acres of almonds was established in the San Joaquin Valley, with by an ARS scientist at the San Joaquin Valley Agricultural Sciences Center, Parlier, CA, four growers and their pest control advisers, and an industry scientist based in Bakersfield, CA. Baseline data on navel orangeworm population levels and almond damage were collected for one season so that the improvement in control in subsequent years could be demonstrated. Adoption of mating disruption will reduce both damage to almonds and insecticide use throughout the entire multi billion dollar almond industry in California.

2. Mating Disruption using Sex Pheromone for Control of Naval Orangeworm in Walnuts. Currently, insecticides and sanitation are the only methods used to control navel orangeworm (NOW), the primary pest of walnuts in California, producer of 99% of the walnuts in the U.S. An ongoing program to evaluate mating disruption to control the codling moth and mating disruption of navel orangeworm was added to the NOW areawide pest management project in some orchards in the northern Sacramento Valley. One UC Berkeley and one UCCE Davis scientist, in collaboration with other UCCE farm advisors, evaluated the efficacy of navel orangeworm mating disruption in 200 acres of walnuts. Mating disruption reduced walnut damage and this study will be repeated on expanded acreage. Adoption of mating disruption will reduce insecticide use in walnuts and reduce navel orangeworm damage and help protect the $500 million dollar walnut industry.

3. The Impact of Mating Disruption on Beneficial Insects and Other Almond Pests. It is not known how reduced insecticide use associated with navel orangeworm mating disruption will affect populations of the peach twig borer, obliquebanded leafroller, fruittree leafroller, and oriental fruit moth, as well as beneficial insect species in almond orchards in the San Joaquin Valley. One UC Berkley researcher, using a 2,000 acre San Joaquin Valley almond demonstration site established by an ARS scientist based at the San Joaquin Valley Agricultural Sciences Center, Parlier, CA, collected baseline population data on the prevalence of almond pests and beneficial insects. This information will help growers using mating disruption optimize pest control and facilitate adoption of this technique. These changes in management practices will decrease both the use of organophosphate insecticides and damage in the multibillion dollar almond industry.

4. Changing Sanitation Guidelines for Navel Orangeworm in Almonds. The primary nonchemical method used to control navel orangeworm in the Sacramento and San Joaquin Valleys is sanitation. An industry scientist in Bakersfield, CA, a USDA scientist at the San Joaquin Valley Agricultural Sciences Center, Parlier, CA and a UC Davis scientist evaluated current sanitation guidelines for the Sacramento and San Joaquin valleys. They concluded that the guidelines need to be more stringent for the San Joaquin Valley and created an educational interactive spreadsheet emphasizing these new standards to be distributed to growers by UCCE farm advisors and the Almond Board of California. The revised sanitation guidelines will reduce navel orangeworm damage and insecticide use in the multibillion dollar almond industry.

5. Navel Orangeworm Population Levels and Aflatoxin Contamination of Pistachios. Navel orangeworm damage is associated with contamination of pistachios by aflatoxins, however the relationship between navel orangeworm population levels and populations of the aflatoxins-producing fungi is unknown. One UC Davis researcher at the Kearney Agricultural Research Center, Parlier, CA, in collaboration with an ARS scientist at the San Joaquin Valley Agricultural Sciences Center, Parlier, CA, determined that the prevalence of aflatoxin-producing fungi in adult navel orangeworm throughout the season was directly related to increase in navel orangeworm population. This research will help reduce aflatoxin contamination of pistachios and decrease load rejection by foreign markets, enabling growers to optimize their control strategies and maximize their economic return in this $500 million dollar industry.


Last Modified: 4/19/2014
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