Post harvest Management of Horticultural Crops (2+1)

Susceptibility to disorders

Susceptibility to disorder depends on various factors

1. Maturity at harvest (immature fruits are more susceptible)
2. Cultural practices- pruning, moderate thinning, preharvst Ca spray such as calcium chloride CaCl2, calcium nitrate Ca(NO3)2
3. Climate
4. Position of fruit- fruit located on vigorous, leafy, upright growing branches have a greater potential to develop bitter pit than does fruit that develops from spurs or on horizontal wood near the tree's main frame
5. Age of the tree- older trees, which are less vigorous and produce larger crop loads, reduce their susceptibility to bitter pit
6. Fruit size (bigger size apple more prone to bitter pit)
7. Harvest practices- preharvest sampling and pre-cooling


The risk of a fruit developing a particular disorder can, therefore, be minimized by identifying susceptible fruit batches and not storing them for prolonged periods. However, the market often has a preference for types of fruit that are highly susceptible to a disorder.
For eg.: the consumer often prefers large apples with intense red colouration, even though such fruits are susceptible to low-temperature breakdown. Thus, methods needed to be developed to successfully store susceptible produce and meet consumer requirements.

Various temperature-management programs have been developed to minimize the development of specific low temperature-related storage disorders. For some produce (e.g. persimmons, nectarines), visible symptoms of chilling injury may develop later and be less severe at temperatures closer to 00C than at higher storage temperatures (e.g. 2-50C).