S06 - Session P6 - Technologies and post harvest methods for successful horticultural production - Successful cold storage of blackberry and raspberry plants

Authors: Femke De Vis *, Ann Schenk, Dany Bylemans

Each year, raspberry and blackberry growers experience multiple plant health problems associated with cold storage including fungal infections, poor bud break and even complete plant loss. Cold storage of plant material is expensive and risky. The development of a good strategy that limits plant quality loss due to refrigeration is therefore important. During a four year study, several parameters were optimized to reduce plant loss after cold storage. The study evaluated cropping techniques during the nursery phase and the cooling process. For example: Plant material should be packed in dry conditions. Wet packing of plants (in rain or high RH) will give fungi a greater opportunity to infect and spread. It is also recommended that packing material is sufficiently perforated. A completely sealed bag can lead to an accumulation of CO 2 , heat and moisture, especially at the beginning of the cooling process, when the plant is still warm and active. A dynamic chilling pattern is generally recommended. Dropping in too large increments creates a temperature shock causing chill injury. High CO 2 concentrations during storage is detrimental to bud break and subsequent production in blackberry and raspberry. These guidelines were compiled in a guide: "Preservation of plant material for cold storage".