Potato Review

www.potatoreview.com POTATO REVIEW JANUARY/FEBRUARY 2023 35 Direct injection e direct injection system has two hoppers, which are lled with neat chemical. A peristaltic pump then delivers the product straight into a pressurised spray line, avoiding the need to pre-mix spray solution. William says it is much more convenient at the end of a shift, with no need to leave any pre-mixed solution in a tank overnight, which has the potential to settle out and require agitation the next day. “You just turn o the chemical and ush it through with clean water. We’ve found it to be so accurate as well,” he adds. In the past, the business had tried early Gavel treatments straight o the eld, but as the tubers were mixed sizes and seed tuber treatments can no longer be applied to potatoes destined for human or animal consumption, this was abandoned. William says everything is now split graded before running it over the roller table, so he knows exactly what the seed size is and what speed the line needs to be working to get accurate and even dosing of product. Oversize seed also goes untreated. “You’d sometimes get an uneven ow of tubers when sizes were too mixed, and we didn’t want any over or underdosing or wasted chemical. “Splitting rst gives us extra work, but it means we make very few adjustments and don’t spend the day chasing the right speed. Combined with the peristaltic pump, it means we are getting very accurate dosing,” he said. Wise investment In the past the use of liquid pre-planting seed tuber treatments has been associated with emergence problems, but this is not something that William has seen across his seed crop area with around 90% of his own input stock getting a liquid treatment. He doesn’t actively encourage growers to have seed treated at source, believing it is better to invest in facilities and equipment to treat once seed is delivered. However, he is keen to expand direct sales of varieties like Maris Piper and Desiree to UK growers and because he has the right tools for the job, has no qualms about doing it when dealing with the customer direct. “It makes it easier, as there is no middleman and you know exactly what has happened to the seed between here and the customer,” he said. Flexible powder e remaining 10% of William’s input seed receives a powder tuber treatment on-planter for Rhizoctonia control, with RhiNo DSG the only product remaining on the market. is superseded RhiNo DS, with the new formulation improving adherence to tubers. Although he would like to transition to liquid treatment on a greater proportion of his crops, he likes the exibility that the powder can provide, as cropping plans often change at late notice. “Particularly on high-grade seed that comes in, it might only be small amounts and we don’t always know exact areas of each variety we need to plant. If you blanket treat with liquid, any leftover seed can’t be used as stockfeed, and you’d also have to swallow the application cost, so it can be a double whammy,” he said. SEED TREATMENT Business Facts – AJ Allan, Brechin, Angus • Subsidiary of IPM Potato Group • Growing 165ha of high-grade seed potatoes on rented ground • 40% for export, 60% domestic market • Most contracted, with some direct sales of Maris Piper and Desiree to UK growers • Key export varieties include Cara, Slaney, Burren, Galactica, Fandango, Bu alo, Desiree, and Berna • Key domestic varieties include Nectar, Electra, Bu alo, Buster, and Maris Piper • Good quality storage with positive ventilation helps keep seed healthy • Modern tuber treatment kit helps protect against storage and seed-borne diseases “It has made the whole process much cleaner, simpler, and safer for the operators and we know that the twin rotating nozzle system gives us phenomenal coverage. “ AJ Allan’s operations manager William Reekie says investment in the best tuber treatment application kit has made treatment cleaner, simpler and safer, and guarantees good coverage of his seed with fungicide The recent addition of a direct injection system like this one has made dosing more accurate, more convenient for operators between shifts, and when switching between fungicide products Gavel (imazalil) is an important base coat for export and domestic orders to reduce risk of storage diseases like dry rot, gangrene, skin spot and silver scurf