New recommendations for the use of potato desiccant Reglone will allow growers to desiccate their crops in all soil conditions, according to Jon Ogborn, technical manager at Syngenta.
Field trials have shown that an initial low 1,0 l/ha dose of Reglone will start dessication, posing no threat to tuber quality, even in dry soil conditions.
“Growers can safely follow the initial application with up to 3.0 l/ha, five to seven days later, to complete with dessication process,” Ogborn said. “The initial low dose is sufficient to stop tuber bulking and initiate skin set. However, the gentle shut down of the plant minimises risk of internal vascular browning, and allows stolons to detach from tubers cleanly, ensuring optimum tuber quality.
“Growers can complete the desiccation process with an additional Reglone application.”
Ogborn also recommends that growers undertake the in-field SMART test (Soil Moisture Assessment for Reglone Treatment) before applying the product.
Previously, growers were advised to avoid using Reglone if the soil failed the test. But Ogborn advises that Reglone can still be used if the soil fails the SMART test, or has a borderline status, although the initial application should be limited to no more than 1.0 l/ha.
“If soils pass the SMART test we would advise that the initial dose may be up to 2 l/ha, depending on crop vigour, followed by a subsequent application of up to a total of 4 l/ha of Regone per crop. In trials, 1.5 l/ha followed by 2.5 l/ha has proved to be a very effective treatment,” he said.
Ogborn claims that the low dose of Reglone will also benefit growers who flail potato crop haulm. “The shock of instant defoliation with mechanical flailing can result in the highest levels of tuber damage and vascular browning,” he said. “Using Reglone to trigger the plants into senescence five to seven days before you plan to flail can really help to minimise the risk of damage.”
A split dose Reglone programme costs around £45 per ha, under half that of acid application, and 50 per cent cheaper than flail and spray desiccation.
He said: “There is now the real opportunity for all potato growers to make a significant saving in desiccation costs, while still achieving equally good, or better, control of tuber size and tuber quality.”
