Entrust vs. Pyganic Insecticide in Perimeter and Internal Trap Crops in Organic Winter Squash

Project Overview

FNE10-686
Project Type: Farmer
Funds awarded in 2010: $5,207.00
Projected End Date: 12/31/2010
Region: Northeast
State: Massachusetts
Project Leader:
Nancy Hanson
Hampshire College

Commodities

  • Vegetables: cucurbits

Practices

  • Crop Production: application rate management
  • Education and Training: extension, farmer to farmer, on-farm/ranch research, workshop
  • Pest Management: biorational pesticides, botanical pesticides, chemical control, economic threshold, trap crops
  • Production Systems: organic agriculture

    Proposal summary:

    In previous SARE-funded studies, we developed organic perimeter trap cropping (PTC) methods for control of cucumber beetle (CB) in winter squash, settling on Entrust for the PTC plants and Surround for the main crop; then we tried adding internal trap crop (ITC) rows to PTC plots to see if they act as additional sinks for CB and further reduce their numbers in main crops (vs. acting as a source to increase CB), and last year we found an apparent sink effect, where ITCs further reduced total CB numbers beyond PTCs alone.

    Here we propose to continue studying this sink effect and also compare PyGanic with Entrust as another possible PTC and ITC insecticide treatment. Finding alternative pesticides can help slow the evolution of resistance, offer cheaper alternatives, and show different effects on natural enemies. As before CB will be scouted and controls applied as needed, and CB numbers in all plants mapped to show CB distributions. We will delay applications to ITCs after first spraying PTCs, to see how different sprays act in the PTCs as an initial barrier, thus adapting the study more specifically to the case of PTC and ITC crops combined as well. We will also sample natural enemies in all crops.

    Our results will be presented on a workshop tour during the 2010 NOFA summer conference and published in farm periodicals such as the UMass Vegetable News Notes.

    Project objectives from proposal:

    This year, we will again compare cucumber beetles in plantings on the farm within our CSA squash, with Perimeter Trap Crops(PTC) and Internal Trap Crops(ITC). We will also compare PyGanic and Entrust to the perimeters (with Surround applied to all interiors), and also note effects on natural enemies.

    In this study, as before, Cucumber Beetle (CB) infestation and foliar damage will be monitored and recorded. We count insects on every plant in the experiment, on most days during the early part of the season. We will also collect data on natural enemies such as spiders seen in the counts and try other methods for predator and parasitoid collection and counting including sweep nets or sticky traps. This data will be statistically analyzed and our results will be presented at the NOFA summer conference and published in vegetable production trade periodicals.

    The available field area for squash this year will thus be set up as a large PTC production field, with ITC plantings and main crop sampling areas set up inside, to consist of 2 treatments in 4 replicate randomized sets or blocks. We will be able to literally map the distribution of CB for maximum use of the field as data, as well as focus on sets of plants in comparable locations for statistical comparison of CB numbers on main squash vs. PTC and ITC plants (which we could also compare as split-plot treatments within plots.

    A tentative experimental design map is included on the Extra Page (Figure 2). There is a total or 14 rows of 36 squash plants each. The plots will consist of winter squash (e.g., butternut) as the main plot variety and buttercup again this year as the perimeter trap crop (PTC) variety, as we did in 2008 and 2009. Squash will be planted as transplants with 80” (2m) between rows and 3’ (0.9m) between plants within rows. The trap crops will be in one row along the edge of plots, and 1 m deep at the ends of plot rows, to define each plot perimeter. This planting pattern allows mechanical cultivation along all the crop rows, and also gives of the main variety inside of each plot for insect sampling and harvest.

    We will use Entrust and Pyganic as needed by economic thresholds at labeled rates and the Surround (the kaolin clay coating treatment; 25lbs/A) applied only to center main variety plants before planting, with the added condition that we will delay the treatment of ITCs after PTCs by at least a day to see how CB move from sprayed PTC to ITC for each pesticide.

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.