The potato moth invades! Here’s how to get rid of it

The potato moth is becoming an increasingly serious problem for potato producers, especially in this period when the tubers of the early variety are mostly plucked, while the extraction of the tubers of the medium variety has just begun or is expected soon. With the late assortment intended for autumn production, the yellowing phase varies. At higher altitudes, potatoes are in good condition and the tops are still green.

On pheromone traps, increased catches of potato moth adults were registered, especially in the regions of Šabac, Novi Pazar, Niš, Leskovac, Negotin, Jagodina, Čačak (lower altitudes), and Novi Sad. The wave of tropical temperatures and the absence of precipitation, which are announced for the next period, affect the accelerated development of the potato moth and its further increase in its number, which further accelerates the decay of cumin and damage to the banks. In these conditions, the risk of being attacked by the potato moth becomes the greatest.

What should I do when the potato moth attacks my tubers?

We are entering a risky period for protecting potatoes from moths. It is important to take all available control measures, especially in areas where potatoes are traditionally grown and where significant damage to autumn potatoes has been registered for years. The following measures are recommended for assortments where the stem has failed and where tubers are expected to be removed:

• As soon as possible, remove and store the tubers immediately after the decay of the cyme. Do not leave plowed potatoes on the plot during the night or in yards because the tubers are directly exposed to moth attack.
• After harvesting, store the potatoes in warehouses with a controlled temperature below 10°C.
• Provide potato warehouses with dense nets at all openings to prevent the entry of adults and further development of the moth.
• When bringing the tubers into storage, a biological insecticide based on azadirachtin (Ozoneem trishul 1% EC in application concentration of 0.3%) can be applied.

For late varieties and crops that will not be harvested in the near future, the following measures are recommended:

• Keeping the soil compact by irrigation to prevent the creation of cracks and the penetration of female moths to the tubers where they lay their eggs.
• Covering and forming a regular and high bank in order to prevent the banks from “collapsing” due to frequent irrigation, which preserves the tubers until the moment of extraction.
• Implementation of chemical protection measures in endangered regions with registered insecticides.

In potato crops with a late assortment that are in the irrigation system, and at higher altitudes where it is necessary to preserve the leaf mass, it is recommended to continue protection against the two most important pathogens of potatoes: the cause of blight and black spot, using appropriate fungicides.

In conditions of tropical temperatures, the effectiveness of insecticides decreases, so treatments should be carried out in the late evening or early morning hours in order to achieve the best protection effect. All these measures are necessary in order to successfully fight the potato moth and preserve potato production.

Source: Farmer