Sprout inhibitors

IPC-CIPC
The most widely used chemicals for sprout inhibition in potato storage are propham (isopropyl-N phenylcarbamate) - [IPC] and chlorpropham (isoisopropyl-N-(3-chlorophenyl)-carbamate) - [ClPC].
IPC-CIPC are very effective at a temperature range of 6-9 oC. Up to 15oC the product has still an effect, but above 16oC the effect decreases quickly.
Dust application-----Liquid application-------Swingfog-------Pulsefog

Powder
The powder formulation has usually 1% active ingredient (main component ClPC). The powder (1kg per tonne potatoes) is applied at the time of loading the store.
One treatment is sufficient to keep tubers free from sprouting for about 8 month when the temperature in the store is 6-8 oC.
Powder applied on immature or not properly cured potatoes may cause skin injury.

Liquid
The liquid is applied with swingfog or pulsfog equipment which atomizes the chemical at high temperatures. The atomized compound is then distributed over the potatoes through the internal forced ventilation ventilation and airdistributon system. The first application in the liquid formulation has to be started before sprout growth starts and has later to be repeated several times (up to 3-4 treatments) when storage is prolonged. In total not more than 65-80 ml liquid per tonne is applied. A delayed application may cause formation of internal sprouts in the tuber.

Processing industry
To keep the reducing sugars in potatoes sufficient low potatoes for processing are stored at a temperature range of 6-8 oC. After 3-5 months of storage at these temperatures the potatoes will develop sprouts. In this circumstances (long storage at relative high temperature) sprout inhibitors are needed to control sprouting.

Seed potatoes
Propham and chlorpropham should not be in contact with seed potatoes, since the products have a bad effect on the sprouting of the tubers. It is recommended not to store seed potatoes not in building where these sproutinhibitors are used.

Talent (D-karvon)
In conditions that chlorpropham can not be used (e.g. biological production, in stores where chlorpropham may not be used, for market that do not accept potatoes treated with chlorpropham) Talent (D-karvon) can be used as sproutinhibitor. As sproutinhibitors powder and liquid formulation are used.