Potato maincrop harvesting is set to get underway, with most growers now counting the cost on yield potential after the late planting in difficult conditions, followed by extreme heat and drought.
Where establishment was significantly delayed, growers are being reminded to check the pre-harvest interval from the date of planting, to desiccation and lifting, advocates Syngenta Potato Technical Manager Michael Tait.
After the use of Nemathorin, there is a 17 week (119 day) minimum interval from application to desiccation or green-top lifting.
“Typically most second-early and maincrop fields have a significantly longer growing season than this PHI,” he pointed out. “However, it is essential that growers check and record the harvest interval, to ensure they fulfill the requirement.”
This year, following the late planting season, many growers could leave crops for longer to bulk up, after slow development in hot dry conditions. That could extend their time in the ground beyond the PHI, Michael added.
To help growers and agronomists check the length of growing season for individual fields this year, and in future seasons, Syngenta has introduced the on-line Nemathorin Harvest Interval Calculator.
Users simply log onto the web page, key in the details for a field and the tool calculates the minimum 119 day interval from Nemathorin application to desiccation or green top lifting.
The calculator enables multiple fields to be checked and a record of the results to be printed.
Furthermore, if there is any reservation over the influence of seasonal conditions when lifting close to the PHI, Michael recommends a pre-harvest sample dig and residue test is conducted.