15 June 2022, USA: An insect with a penchant for potato plants continues to be a challenge as it exhibits tolerance or resistance to multiple modes of action.
“If you want to categorize insects in terms of importance for potato growers, Colorado potato beetle is at the top of the list,” says Kiran Shetty, Ph.D., a technical development lead for potatoes at Syngenta. “The insect can be devastating – destroying a crop in as little as a few days if the outbreak is severe. Colorado potato beetle overwinters in the previous year’s crops and particular weeds of its fancy and can be very dynamic, with two and even three generations possible in a given season.”
To add to the beetle’s historic reputation for causing an economic impact in potato fields, Colorado potato beetle (CPB) has shown levels of resistance to multiple modes of action. Colorado potato beetle also is increasingly difficult to control, showing overlapping generations in recent years rather than the distinct first and second generations growers saw in past years. Shetty says this shift in behavior can impact insecticide efficacy on beetle populations, increasing the risk for negative impacts on potato plant health and overall yield potential.
Using cultural practices and scouting methods, along with a robust pest management program, can help keep Colorado potato beetle populations down. Shetty recommends growers pay close attention to the generational cycles of CPB in their given geography and prioritize thorough, early scouting to help ensure early-season populations are as low as possible to establish healthy plants.
Shetty recommends a three-step, integrated approach with a focus on products that are most effective against Colorado potato beetle:
- At plant: “To establish a high-quality, high-yielding potato crop, growers should start with a neonicotinoid like CruiserMaxx Vibrance seed treatment,” Shetty says.
- Early season: ”After planting, follow up with an application such as Minecto Pro insecticide, which complements a foundational neonic program,” Shetty says. “Minecto Pro can knock the population down low enough to offer an advantage for the rest of the season. Remember, you’re targeting CPB, but an integrated approach with broad-spectrum control is key to managing an array of insects.”
- Mid-season: “For good resistance management, finish up the season with different modes of action not already applied to the field. Adopting an integrated pest management program that includes scouting, using historical information on a field relating to pesticide use, rotating crops and record-keeping is crucial,” Shetty says.
Ultimately, Shetty says, “A strong integrated pest management program helps achieve a stronger crop stand, higher quality potatoes and, ultimately, better yield.”