Plum Curculio Control in Sweet Cherry, 2016*

The objective of this trial was to test the efficacy of various compounds against PC in sweet cherry. Two-tree plots were established in a 19-yr-old “Hedelfingen” sweet cherry planting (Sweet Cherry 3, row spacing 20′ × 15′) located at the Trevor Nichols Research Center in Fennville, MI. Treatments were replicated four times in an RCB design. Test materials were applied with a tractor mounted FMC 1029 airblast sprayer calibrated to deliver 100 gpa at 2.5 mph. Applications began at petal fall on 17 May with a 7-day interval. Applications were made per Table 1. In addition, foliar maintenance applications of Kocide, Bravo Weather Stik, Rally, Orbit, Gem, and Indar were applied as covers across the entire block. 2, 4-D Weedar was banded below the trees for weed control.

Field Evaluations consisted of inspecting 100 fruit per plot for the presence of PC stings. Evaluations were made on 9 and 22 Jun. On 17 Jun, a harvest time sublethal effects evaluation was performed for Rimon and Dimilin treatments, compared to the untreated check. Two-pound samples of fruit were randomly harvested from each plot. The fruits were then placed on wire racks. Mature larval PC emerged from the fruit and dropped into trays containing a quarter-inch layer of dry sand. On 13 Jul, sand was sifted through window screen and larvae were counted. Data are presented as mean number of larvae (Table 1). While actual counts are presented, ANOVA was conducted on square-root transformed data. Transformed treatment means were analyzed using ANOVA and means separation by Tukey’s HSD at P = 0.05.

The Apta/Actara/Avaunt and Imidan/Actara/Avaunt treatments showed significant fruit protection in terms of direct effects on PC, compared to the untreated check (Table 1). Rimon and Dimilin treatments significantly reduced the survival of PC larvae in stung fruit via sub-lethal effects.

Author notes