• Print
• Share

Storage Disorders in 'Honeycrisp' Apples

'Honeycrisp' is extremely sensitive to cold temperatures in storage and will readily develop soft scald and low temperature breakdown (a.k.a. soggy breakdown) when held at the low temperatures recommended for most other apple cultivars.

Soft scald is characterized as sharply defined, irregularly shaped, smooth brown lesions of the peel (Photo 1). It may also damage some of the underlying hypodermal tissue. Lesions are often invaded by secondary infections, such as Alternaria or Cladosporium, resulting in diffuse black rots. Higher incidence of soft scald is usually associated with large apples, light crops, over-mature fruit, and dull cool wet summers. The disorder is induced by low temperature, so apples subjected to rapid cooling or placed closer to the colder air of the evaporator coils are more susceptible. Development of soft scald stops when apples are removed from cold storage.

Photo 1: Soft scald in "Honeycrisp"

Low temperature breakdown is well-defined diffuse browning of the outer cortex, which is usually moist and separated from the skin by healthy tissue (Photo 2). In 'Honeycrisp' the damaged flesh tissue is extremely soft and spongy and therefore, the term soggy breakdown is also used. This disorder is augmented with advanced fruit maturity, cool weather late in the growing season, and controlled atmosphere storage. The conditions listed above that promote soft scald will also exacerbate soggy breakdown in 'Honeycrisp'.

Photo 2: Soggy Breakdown in Honeycrisp'

The 2008 apple season produced fruit very susceptible to chilling-related disorders. As such, there was a lot of soft scald and soggy breakdown observed in 'Honeycrisp' apples this year. To reduce the incidence of these disorders, 'Honeycrisp' must be stored at 3-5°C. In addition, a cooling delay consisting of 5 days at 10°C prior to colder storage will help reduce the incidence.