By Kristian Holmstrom, Vegetable IPM Research Project Coordinator, Rutgers Cooperative Extension.
Integrated Pest Management (IPM) is a system that helps farmers anticipate and limit pest problems before they reach destructive levels. As the name implies, IPM integrates all practical management strategies to increase profitability, conserve energy resources, and maintain environmental quality without adversely affecting the yield and quality of agricultural products. The Rutgers Cooperative (RCE) Vegetable IPM Program in New Jersey was initiated in 1972, to assist sweet corn growers in managing insect pests responsibly. It has since expanded to include many of our state’s vegetable crops and has become a platform for dissemination of pest information throughout the agricultural community.
The goal of the RCE Vegetable IPM Program is to assist farmers, consultants, and extension educators in making the best possible management decisions in protecting crops. It is expected that IPM growers will maintain high quality produce while minimizing production costs, consider non-chemical means of mitigating pest issues as a first line of defense, and use agricultural chemicals efficiently and only when necessary.
In the RCE IPM Program, field technicians work closely with participating growers, monitoring crops twice a week for insect and disease pests, allowing for timely decision making. Additionally, most participating farms have insect survey traps, which are also checked twice a week. Insect and disease pressure in the crop fields is quantified, and target insect pests from trap captures are counted, with all information reported to the growers. Upon pests reaching critical levels (action thresholds) in trap collections or field assessments, growers are provided with recommendations, and must decide how to manage the pest. The information gathered from farm visits is also disseminated to a wider audience via weekly publication of the Vegetable IPM Update in the Rutgers Plant and Pest Advisory online newsletter.
Management options for the farmer depend upon the pests that need control and the stage of crop development. For example, finding pest insects or disease on the crop leaves in seedling plants may require different control methods than finding the same pests on mature plants that are near harvest.
Examples of control tactics that may be employed by growers include:
Varietal Resistance
When available, a first option is to plant a crop variety that is pest resistant. This can greatly reduce or eliminate the need for pesticide use on the crop. Varietal resistance is typically used to help manage plant diseases, and growers must anticipate disease issues in this case, purchasing seeds with the appropriate resistance packages prior to the growing season.
Cultural Control
Examples include disruption of pest life cycles through soil cultivation, rotating crops by location from year to year to avoid pest buildup, and manipulating the local environment to improve drying conditions within the crop, making it more difficult for diseases favored by leaf wetness.
Mechanical
Various types of physical barriers may be used to separate the pest from the crop. Common types are netting, row covers, and screening. Growers must know when to remove row covers if bees are necessary for pollination.
Sanitation
This involves the removal or destruction of potentially diseased or insect-infested crop residue that may serve as a reservoir for harmful organisms potentially damaging to later crops. Additionally, seeds may be hot water treated to eliminate some pathogens, and tools and production equipment may be sanitized to prevent disease spread.
Biological Control
IPM may use natural enemies (such as ladybird beetles, predatory mites, parasitic wasps, etc.) to limit pest numbers. Native beneficial insects are encouraged to populate crops by placing flowering plants nearby that provide resources (pollen, nectar, cover) to those insects. In addition, biological insecticides composed of bacteria, viruses, nematodes, or plant derivatives are used when possible.
Pesticides
When necessary, conventional pesticides are used with restraint, and are based on pest pressure reaching actionable levels. This optimizes efficacy while limiting potentially harmful effects on non-target organisms.
The RCE Vegetable IPM Program actively monitors for insects and diseases on approximately 65 commercial farms in New Jersey, with far greater outreach through web-based publications (see below). IPM is a major part of vegetable production on New Jersey farms, helping agriculture remain viable. Additionally, the Rutgers Vegetable IPM Program provides real-time status updates on certain insect pest populations so that researchers, consultants, and gardeners can make more informed decisions regarding pest management. For access to current vegetable IPM-related information during the growing season, growers and home gardeners are encouraged to subscribe to the Rutgers Plant and Pest Advisory, Vegetable Crops Edition: plant-pest-advisory.rutgers.edu/category/jersey-vegetable-crops. Free email or smart device subscriptions are available at this site.
Rutgers also has vibrant IPM programs for tree fruit and greenhouse growers. Collectively, RCE’s IPM programs seek to assure consumers of New Jersey farm fresh produce that their growers are utilizing the best information to be economically and environmentally sustainable.
This article originally appeared in the May, 2021 issue of Gardener News.
