The effect of timing of application of CIPC on sprout control efficacy

At the time the research was commissioned CIPC was the main sprout suppressant used on stored potatoes in GB. It was of particular importance to the potato processing industry because there were no alternatives available. It was recommended that the first application of CIPC should be made before sprout growth was initiated, as late application of CIPC was considered to be associated with relatively poor sprout control efficacy. Trials were carried out to provide independent data on the importance of the timing of initial CIPC application for sprout control efficacy.

There were variable results between the two years' trials. Low levels of sprouting in year 1, and high levels of sprouting in year 2 made it difficult to draw conclusions that could be used to update advice on the timing of CIPC application.

Effective sprout control was observed at store unloading in the cultivars Fianna and Russet Burbank following late application of CIPC. Similar applications, but at earlier timings, did not result in effective sprout control. The measured deposit and residue levels (0.40 mg kg-1 & 0.11 mg kg, respectively) are likely therefore to have provided an indication of the minimum effective dose of CIPC required for sprout control.

The last approved use of CIPC as a sprout suppressant on potatoes was in 2020.