The dry fall and winter may be a boon to the $40 million New Mexico chili crop, which in wet years can be hit hard by a tiny, virus-carrying insect.
Virologist Rebecca Creamer, an associate professor in New Mexico State University’s entomology, plant pathology and weed science department, expects a loss in New Mexico’s chili country of just 1 percent to 5 percent due to the curly top virus, which is spread by the tiny beet leafhopper.
That would be a much smaller loss than experienced by farmers in 2001, when a wet fall and winter helped leafhoppers thrive and caused 30 percent to 50 percent crop losses.
“We seem to have it worse in odd years, for whatever reason,” said Creamer, who has been studying the insect for NMSU since 2001. Losses were only a half percent to 1 percent in 2002 and 5 percent to 10 percent in 2004. Last year, 20-percent losses to the chili crop were compounded later in the season by 50 percent losses to pumpkin growers in Torrance County.
Leafhoppers take refuge in weeds that grow through the fall and winter, especially London rocket, a member of the mustard family that can flourish in the Rio Grande Valley. Wet years mean more weeds and better conditions for leafhopper survival.
In late April and early May, leafhoppers move from weeds into cropland, sometimes traveling 50 miles or more.
“They are good fliers and they move with wind currents,” Creamer said. Even though the leafhoppers that farmers find on their fields may have come from miles away, it’s still a good idea to keep weeds as controlled as possible to eliminate shelter for the insects.
“Be diligent with weeding,” Creamer said. “If they don’t have to move very far to find food, even the poor fliers can transmit the virus.” Creamer also suggests farmers plant more chili seed and let the virus do their thinning, especially in a year when relatively low losses are expected. The use of insecticide also can help control leafhoppers, but that’s not economical in a light year.