Corn nematode control tools
Chlorosis. Stunting. Root damage. Yield loss. So which of the many maladies that annually impact your corn cause these symptoms?
Could be herbicide damage. Could be soil compaction. Or it could be a newcomer that’s actually been around a lot longer than you think: corn nematode.
Corn farmers who also raise soybeans already know about nematodes, due to soybean cyst nematode (SCN) infestations. Unlike SCN, though, there are 60 species of nematodes that can impact corn, says Cliff Watrin, Syngenta Seed Care technical crop manager.
Economic thresholds for corn nematodes vary, depending on the type. For sting nematode, the threshold is just 1 to 10 per 100 cubic centimeters (cc) of soil, says Watrin. Others, such as lance, can tally between 50 to 100 per 100 cc of soil before yield damage occurs.
Changing production practices are causing this pest to damage more corn. “We are using less organophosphate and carbamate (soil-applied) insecticides and more pyrethroids,” says Tamra Jackson, University of Nebraska Extension plant pathologist.
A side benefit of organophosphate and carbamate soil-applied corn rootworm insecticides is they also control corn nematodes. Moving toward more pyrethroid insecticides and corn rootworm traits nixes this perk.
More no-till also prompts more corn nematodes to thrive. Numerous species of corn nematodes thrived in undisturbed U.S. native grasslands before European settlers tilled them. No-till mimics this natural state.
More corn-on-corn – also a grass – gives corn nematodes what they prefer to eat. “It is what we consider ice cream for corn nematodes,” says Jackson.
There are a couple new corn nematode-control products on the market to help farmers. In 2010, farmers were able to control corn nematodes under a seed treatment combination Syngenta Seed Care calls Avicta Complete Corn. Its five components include:
• Avicta seed treatment nematicide.
• Cruiser seed treatment insecticide.
• Seed treatment fungicides Apron XL, Maxim XL, and Dynasty.
Avicta Complete Corn’s suggested retail price is $20 to $27 per 80,000-seed unit before seed company discounts, says Mark Jirak, crop manager for Syngenta Seed Care. It also is incremental above the standard Crusier Extreme 250 treatment that’s seamlessly priced into a corn seed unit today, he adds.