Risk of Storage Disorders in Apples for 2021-22 Season

CIPRA is a computer-based program developed by the research team of Dr. Gaétan Bourgeois (AAFC-QC) that uses weather data to predict the risk susceptibility of apples to specific storage disorders (Bourgeois, DeEll, and Plouffe). According to CIPRA models using weather data up to September 14th (2021) from Delhi (Norfolk County, ON), there is some risk (~9%) of apples developing chilling-related flesh browning disorders during the current storage season (Figure 1).

Figure 1.  Risk of developing chilling-related flesh browning disorders during the past 30 years (1992-2021), for the region of Delhi (Norfolk County), Ontario. * Graph supplied by D. Plouffe, AAFC-QC

Using specific models for bitter pit and soft scald development, CIPRA with weather data from Environment Canada shows varying risk susceptibility around Ontario (Table 1). For 2021, the Georgian Bay area has the highest risk of bitter pit, while Delhi and Oshawa have the highest risk for soft scald development during storage.

Table 1.  Risk of developing bitter pit or soft scald in four apple producing regions of Ontario for 2021, with comparison to 2020.
Location
2021
Risk %
Bitter pit
2020
Risk %
Bitter pit
2021
Risk %
Soft scald
2020
Risk %
Soft scald
Brantford
0
2
2
32
Collingwood
24
0
1
8
Delhi
0
0
17
26
Oshawa
0
21
17
15
* Data supplied by D. Plouffe, AAFC-QC

Regardless of growing season and annual risk susceptibility, it is important to use the recommended storage temperatures and regimes for specific apple cultivars.  Disorders can develop in any year when appropriate handling practices and storage regimes are not used.  Late harvested apples are also more prone to developing chilling-related disorders, especially flesh browning and soft scald.

Dr. Jennifer DeEll
Dr. Jennifer DeEll

Fresh Market Quality Specialist – Horticulture, OMAFRA