Fungal pathogens inside cotton plants may hold a key to controlling damaging insect pests and nematodes.

Greg Sword, Texas A&M entomologist, says researchers have a lot of work to do to evaluate the efficacy of fungal pathogens for protecting cotton from insects and nematodes.

“Beneficial fungal endophytes have potential to confer protection to plants from a variety of stressors, including nematodes, insects, pathogens and environmental conditions, such as drought,” he says.

Texas A&M research has investigated inoculating cotton with specific fungal endophytes to reduce reproduction rates of both nematodes and aphids. “We evaluated the ability to selectively manipulate cotton endophyte interactions under natural field conditions,” Sword says.

Results were promising. “We’ve identified some promising fugal endophytes, and both lab and field testing are underway. So far, tests have shown seed treatment to reduce aphid reproduction in colonized plants within two weeks.”

Also, he says, anti-nematode endophytes “attacked nematode eggs outside the inoculated plant. They didn’t repel nematodes, but we did see a big reduction in the number of eggs.”

Sword says field testing will resume, with scientists at Lubbock working with root-knot nematodes and scientists in College Station concentrating on reniform nematodes.

Studies have shown better square and boll retention from the colonized plants versus control plots. Yields from the cotton with endophytes have been as much as 20 percent higher.

“We aren’t certain why yields are better,” Sword says. “We’re not certain what the endophyte is protecting against, so we still have a lot of work to do to determine what is going on inside the plant.”