Potato growers are encouraged to carry out pre-harvest residual tests following this year’s long-term dry state.
The Nematicide Stewardship Program (NSP) has issued new guidance urging farmers to assess the risk of crop residues. Particularly when granular nematodes such as nematrin 10G (fosthiazate) are applied during plants.
The conditions of arid soil in spring and early summer may interfere with normal failures and nematode movement through soil profiles.
This is particularly relevant for growers with limited irrigation and those who saved their water early in the season.
The lack of rainfall can reduce tuber bulge and lead to premature aging, both of which can affect crop quality and timing of harvest.
Dr. Allison Warrington, Senior Plant Health Advisor, stressed the importance of following label guidelines and carefully managing product use during such seasons.
The Nemathorin 10G label highlights the important role of soil moisture in exercising a massive initiation (such as rain and irrigation).
It also requires a minimum 119-day interval between application and harvest. This should be observed regardless of the results of the residual test.
NSP chair Patrick Mitton said, “NSP has a long history of promoting the use of best practices and handling of granular fibers.
“The advice provided during this very dry season will help guide producers’ end-of-season actions in collective support for the ongoing future use of granular linear agents such as nematrin 10G.”
Growers who are concerned about the development of insufficient rainfall or stressful plants are advised to carry out pre-harvest residual testing.
Independent agriculture scholar Simon Alexander recommends a thorough sampling approach. “Growers should take representative samples from processed areas and select multiple plant tubers across the field in a “w” shape pattern. A sample of at least 2.5kg of tuber should be submitted for testing. ”
Tests must be conducted by an ISO17025 certified laboratory to meet requirements based on the same as the Red Tractor fresh produce scheme.
Producers can access further guidance at NSP Best Practice Guidelines or Syngenta’s Nematorin Stewardship Centre.
