2020 Apple Maturity Assessments: Week 9 Evercrisp

These fruits are ready to be harvested. As observed for most of the late-season cultivars we have observed high soluble solids contents, which in this cultivar are ~ 19% accompanied by a high percentage of red skin coloration (~85%). As characteristic of Evercrisp, we also observed high flesh firmness values (~22 lbs). Starch patterns are ~6 (Cornell chart) and DA index values are ~0.6. We have observed an increase in the presence of the physiological disorder of watercore, as compared to our previous evaluation. The results are summarized in Table 1. We acknowledge the important contributions of collaborators following the table.

Evercrisp Results

Color

Surface color: Evercrisp fruits presented an average of 85% red skin coloration, which has not changed since our last evaluation.

Background color (DA index): DA index values are ~0.6, which is in the recommended range for harvesting fruits that will be destined for storage.

Fruit firmness

Evercrisp fruits displayed high firmness values (~22 lbs), which corresponded to a 1lb decrease as compared to our last assessment on 10/17. Firmness was measured with a penetrometer with a 7/16-inch diameter plunger.

Starch content

The common starch index rating system (Cornell chart) on a scale from 1 to 8, where 1 is full starch (all blue-black) and 8 is starch-free (no stain), was used to evaluate the fruits. Evercrisp fruits this week displayed a starch index value of 6.0. In general, on a 1 to 8 scale, values ranging from 4-6 are recommended for harvesting apples for long-term storage, while 6-7 for fresh market.

Soluble solids contents (SSC)

SSC values were around 18.7% for Evercrisp, displaying the highest SSC that we have measured so far. We also observed an increased presence of watercore as compared to our last assessment.

Acidity

Evercrisp apples displayed a decrease in their malic acid values from 0.7% (10/17) to 0.6% (10/31).

Acknowledgments

This project was funded by The State Horticultural Association of Pennsylvania (SHAP) and from the start-up funds of Dr. Macarena Farcuh. Special thanks to Joy Cline and to Bear Mountain Orchards, as well as to Matt Harsh and to 78 Acres, LLC that allowed us to harvest fruit for analysis. Thanks to Daniel Weber for harvest support and collaboration. Thanks to all the students in the Farcuh Lab in the Department of Plant Sciences and Landscape Architecture at the University of Maryland, in particular Jared Baker and Jack Graziano for assistance in harvesting and in conducting all the analyses. We also thank Dorothy Shaffer for her assistance in all harvests, Tara Baugher for proofreading, and Dave Myers and Norma Young for posting our weekly assessments in Maryland and Pennsylvania newsletters, respectively.