Potato growers are being urged to prepare now for changes in the potato seed treatment line-up this spring, according to the latest advice from Certis. Charlotte Cunningham reports.

Last autumn, Bayer announced it was pulling sales of its powder treatment Monceren (pencycuron) that was widely used for Rhizoctonia control, citing “uncertainty over its regulatory future” as the key reason.

According to crop protection firm, Certis, this will likely force a big change in application practice, as it was the only powder treatment still allowed to be hand sprinkled on seed tubers, either in the planter hopper, potato boxes or chitting trays.

Statistics show about 30% of powder seed treatment was still manually applied in 2019 and going forward, these growers will have to reconsider how they treat seed, says independent potato specialist Andy Alexander.

One alternative is to order seed for ware crops pre-treated with a liquid treatment of either RhiNo (flutolanil) or Maxim (fludioxonil) or treat the seed on arrival, says Andy. “Only RhiNo can be used on seed for seed crops. It’a going to be a completely different ballgame for some growers and my preference is to switch to a liquid treatment, either applied by the seed supplier or a mobile contractor.

“It’s also possible to invest in the liquid application equipment for the grading line and do it in-house.”

Maintaining flexibility

Those wanting to maintain the flexibility of treating at planting will have to consider an alternative powder product – either RhiNo DS (flutolanil) or Emesto Prime DS (penflufen) – and fit an on-planter powder applicator, as they can’t be applied manually, adds Andy.

“Some businesses will stick with powders and having to move to an on-planter applicator is a positive step, both from an operator and environmental safety perspective.”

Application kit

Certis advises that on-planter powder applicators are available from Techneat and Team Sprayers, but for Techneat’s Powder Pro system, re-calibration is required for any change in product formulation to ensure the correct rate is applied.

The Team Sprayers powder applicator with Digimon control box calibrates automatically within +/- 5% of the set output, allows output to be adjusted from 0.6kg/tonne upwards and can be fitted to all makes of cup or belt planter.