This scouting session for our day-neutral organic strawberry project at the West Madison Agricultural Research Station (WMARS) was conducted Friday, June 15th in the morning. Field conditions during collections were cool, windy, and damp.

This project aims to evaluate the effects of four different film-based mulches (black, white, and reflective plastic mulches, and paper mulch) on strawberry production in an annual, day-neutral system. This system-wide field trial is evaluating yield, fruit quality, pest pressure, and economic feasibility of this regionally novel system for strawberry production. Our field was planted on the 8th of May, and plants are still developing with flowers and runners removed as they appear, with runner removal continuing indefinitely and flower removal continuing until the first week of July. We are irrigating for short intervals several times a week, with fertigation occurring once weekly at the rate of 5 lbs N per acre.

Sampling Methods: 160 plants (40 plants per mulch treatment) were randomly selected and assessed for insect pest and disease presence and respective pressure using the University of Wisconsin Extension BioIPM Strawberry Workbook. At each sampling point, two leaves per plant were tapped into a white tray, and any thrips or tarnished plant bugs were counted. Mites were assessed on an incidence-basis: plants were evaluated for mite presence on older foliage and crowns. Each plant was also inspected for foliar disease symptoms. Declining or dead plants are removed and assessed in the laboratory for biotic causal agents.

Two-spotted spider mites (Fig 1)were again present in this week’s scouting on just over 20% of sampled plants. While the number of plants with observed mites (incidence) remained the same, the total spider mites on each plant (severity) seems to have increased. While there were no whole-plant infestations, the lower, older leaves of infested plants are now covered in mites and beginning to brown and curl. Newer and outer leaves, again, did not seem to be affected.

Thrips were noted this week in slightly higher numbers, though again no associated foliar damage was observed. Flower removals will continue through the end of June, so these pests are currently feeding primarily on leaves. Once flower clusters remain on the plants, we will begin sampling for these insects by tapping flower clusters instead of leaflets.

Tarnished plant bug presence has decreased this week, perhaps due to continued flower removal and the cooler, windy conditions. This past week, we did notice some catfacing, or fruit deformity induced by tarnished plant bugs (Fig 2), on the few volunteer strawberries that were removed.

Date	Mites (Incidence)	Thrips (Average per leaflet)	Tarnished Plant Bug (Average per leaflet)	Spotted- wing Drosophila (Incidence)
6/9/2023	0.21 ± 0.064	0.07 ± 0.07	0.03 ± 0.03	0
6/15/2023	0.21 ± 0.064	0.13 ± 0.1	0.01 ± 0.01	0

In our last report, we noted a few plants in our field showing signs of stunting, collapse, and death. These symptoms could be attributed to multiple possible factors, including disease or drought stress. We are currently testing these plants for the presence of pathogens, and plan to have preliminary results by the end of next week. Based on a whole-field walkthrough, no new plants seem to show significant signs of decline.

Date	Common Leaf Spot	Phomopsis Leaf Blight	Verticillium Wilt	Anthracnose	Leaf Scorch	Neopest- alotiopsis
6/9/2023	0	0	0	0	0	0
6/15/2023	0	0	0	0	0	0

Funding for this project was provided by USDA-NIFA ORG award # 2021-51106-35490.

This article was posted in Berries and tagged Ariana Abbrescia, Christelle Guédot, day-neutral strawberry, DNS, DNS Organic, Jarret Miles-Kroening, Leslie Holland, organic, Organic Day-Neutral Strawberry Production, Organic production, organic strawberries, Strawberries.