Location: Crop Improvement and Protection Research
Project Number: 2038-22000-020-024-R
Project Type: Reimbursable Cooperative Agreement
Start Date: Oct 1, 2024
End Date: Mar 29, 2025
Objective:
Objective 1 – Implementation and optimization of sweet alyssum densities for pest control and the role of landscape context.
Objective 2– Implementation and optimization of annual planting strips for pest control and the role of landscape context.
Objective 3 – Assessment of annual and perennial plants for supporting natural enemies and pest populations.
Objective 4 – Extension of project results and information on use of habitat in vegetable production systems to vegetable growers, pest control advisors, and other industry personnel.
Approach:
Objective 1: Field trials and demonstrations will be conducted cooperatively with several major lettuce producers on the Central Coast to characterize the pest management benefits provided by sweet alyssum. Sweet alyssum will be transplanted with organic romaine lettuce at treatment densities of 2%, 5%, and 8%. Each sweet alyssum treatment will be randomly placed within a field, with each treatment consisting of a minimum of 2 acres. Pest and beneficial insect populations will be evaluated using a variety of methods, including vacuum sampling, pan traps, and caged sentinel aphid studies. For each replicate, information on the surrounding landscape will also be gathered and used to assess if any pest management benefits from sweet alyssum are dependent on particular landscape contexts.
Objective 2: Field trials and demonstrations will be conducted with the same producers and locations as mentioned in Objective 1. Border planting strips of either sweet alyssum, a mixture of annual plants, or no border, will be assessed for their impact on pest management. Planting strips will be established annually and span the outside border of a romaine lettuce field. Pest and beneficial insect populations will be evaluated using a variety of methods, including vacuum sampling, pan traps, and caged sentinel aphid studies. For each replicate, information on the surrounding landscape will also be gathered and used to assess if any pest management benefits from sweet alyssum are dependent on particular landscape contexts. In addition to the landscape data that will be gathered, point counts of birds will be conducted within a week of harvest to address any food safety concerns.
Objective 3: The objective consists of three subobjectives: 3a) Assess annual plants for their ability to support natural enemy and pest populations, 3b) Assessment of hedgerows for their ability to support natural enemy and pest populations and birds. For Subobjective 3a, annual plants (e.g., sweet alyssum) will be planted as a randomized complete block design at the USDA Spence Research Farm in Salinas. Natural enemies, pollinator visits, and pest abundance will be documented over time. For Subobjective 3b, hedgerows will be assessed for their ability to support natural enemy and pest populations using a combination of methods (e.g., vacuuming, sweep netting, pan traps, observations). Point counts of birds will also be conducted in hedgerows, as well as fecal sampling in lettuce crops that are adjacent to hedgerows versus those that are not.
Objective 4: On-farm trials and demonstrations will be conducted with several major vegetable producers on the Central Coast, with the goal of reaching a broader audience and providing networking opportunities and collaborations among attendees and researchers.