Champlain Valley Harvest Maturity Program Report: Week 11
Mike Basedow and Jenn Stanton, CCE-ENYCHP, Northern NY
This week we are reporting on MAIA-1 EvercrispTM, and R10-45 (WildTwistTM as packed fruit). The R10-45 block is ready for spot picking now, while the MAIA-1 block is likely going to be ready later this week into early next week.
This week’s samples were collected on Monday October 21st and processed the same day. Fruit were picked from orchards in Peru.
Sample size is 10 fruit picked for the reddest fruit, from multiple trees, on both sides of the row.
As blocks continue to receive harvest management PGR’s we will update their treatment in the final data column so you can better compare against your blocks.
Due to the large amount of variability associated with strains, rootstock selections, planting systems, the widespread use of ReTain, Harvista, ethephon, and local orchard microclimates, it is impossible to sample and process enough locations to make specific harvest recommendations. ENYCHP HMP data is meant to be used as a general indicator of apple harvest maturity, and nothing more.
When we have them, I’ll also include data from previous years to serve as a comparison.
Weekly Summary of Fruit Maturity Progress
MAIA-1 EvercrispTM for 10/21/2024
Comments: Fruit in the block we are testing are still very hard. They have met the minimum 14% brix, but are still below the recommended target of 16%. Fruit are also still below the 4-5 SPI range for CA storage. Flavor is fairly good in the fruit tasted, but still had a slight off-flavor in the finish. Color could use a few more sunny days to improve on some of the fruit as well. I think this block might be ready for a spot pick late this week into early next week.
“Loose” target maturity indices for MAIA-1, based on Craig Kahlke’s and others testing:
Firmness is not an issue with this variety, 17-21 lbs should cover everyone. Brix – target 16%+ most years, minimum of 14%. Like many of the other new varieties, Starch Pattern Index (SPI) is not super reliable, but target roughly 4-5 on the Cornell chart for CA storage, or 5-6 for regular cold storage. We will test this block again next week if it hasn’t been picked over by then.
Current tentative storage recommendations from Dr. Watkins for this variety include:
- Recommended storage temperature is 38°F.
- 1-MCP is not recommended as it can enhance flesh browning disorders.
- ReTain is recommended to reduce watercore at harvest and physiological disorder development during storage.
- Managing watercore is important to reduce physiological disorder development.
R10-45 (WildTwistTM) for 10/21/2024
Comments: Fruit in this sample had a nice color. Brix is below the recommended 13%. Fruit sampled are currently within the recommended SPI range of 3.5-5. Firmness is holding well. Despite the brix being slightly below the target, given the color, DA, and SPI, I think this block is ready for spot picking now.
For R10-45, the recommendation I have seen for optimal maturity is brix above 13%, SPI of 3.5-5, and 60% red color. Harvesting at SPI of 3.5-5.0 has been reported to maximize the tang from the acidity in this variety. We will test again next week, unless it has been picked over by then.
More research is needed, but tentative storage recommendations to date are:
- Recommended storage temperature is 38°F.
- 1-MCP enhances internal browning.
- CA (2% O2/ 1% CO2) storage maintained flesh firmness and reduced flesh browning incidence compared with air storage.
DCA is recommended for long term storage, and has the additional advantage of maintaining good fruit flavor
Next week we will continue testing MAIA-1 EvercrispTM and R10-45 if they are still on the trees.