Potato Review

www.potatoreview.com POTATO REVIEW JANUARY/FEBRUARY 2023 13 STORAGE Storage specialist o ers tips for overcoming the challenges of latest harvest. T HE 2022 potato harvest has presented growers and store managers with some additional problems when managing crops in store. Given current circumstances, it has become more important than ever to pay particular attention to detail when treating stored crops. Nick Tapp, Director of Juno (Plant Protection) Ltd which produces BIOX-M, a spearmint oil applied to stored potatoes as a hot fog, stressed the importance of ensuring sprout suppression products are used to the best advantage. “E cacy of sprout control products applied to the crop in eld prior to harvest may have been compromised by the very hot, dry summer, conditions not normally well-suited to in eld application. erefore, sprouting may have commenced in the eld before harvest or early in the storage season,” he said. “Crops should be dry and fully cured before any treatment, even if they arrive in store having developed sprouts in the eld.” ere is no need to rush a treatment such as the spearmint fog, he said, pointing out that it is essential that the crop is dry and cured before treatment to achieve the most e ective sprout control and avoid other risks to the crop. Careful temperature management in store prior to treatment is also essential to avoid uneven distribution of fog during application, and to avoid risk of condensation/ coalescence in store. When using products like BIOX-M, Nick advises that refrigeration and ambient air exchange should be turned o before treatment (24 hours is recommended) to ensure an even temperature through the store and crop. Variable temperature(s) in crop during treatment increases a risk of poor e cacy. Multiple store temperature readings should be recorded, when the refrigeration is turned o and immediately prior to fogging to ensure an even store/crop temperature. An even distribution of fog is important in achieving good e cacy, while the speed of introduction of fog into store should not be excessive, so that the fog has time to distribute evenly in the store. Fog should be introduced to store in line with the rates recommended ( for Biox-M this is 100t – 500t 15 litres/hr, 500t – 1,000t 20-25 litres/hr, 1,000t – 1,500t 25-30 litres/hr, 1,500t – 2,000t 30-40 litres/hr, Over 2,000t Up to 60 litres/hr. Visual con rmation of fog distribution is recommended, either using in-store cameras or a clear viewing panel permitting a view of the fog distribution, Nick stressed, adding that fan settings should be adjusted to ensure an even distribution of fog. Intermittent running of fans during application may be more e ective than continuous running to give an even distribution of fog. Stores should be closed for 48 hours following treatment, and longer for part- lled stores or stores at risk of less than optimal distribution of fog. While it may seem obvious, the importance of not opening doors following treatment was stressed, while acknowledging that every store is di erent and should be managed accordingly. “E cacy of sprout control products applied to the crop in field prior to harvest may have been compromised by the very hot, dry summer, conditions not normally well-suited to in field application.” Nick Tapp, Director, Juno (Plant Protection) Ltd ‘Counter the compromised’