The infestation may start in a small area of a field and at first may not be at high enough levels to cause significant losses in crop yield or quality, Steddom said. But if the field is left untreated, it’s almost a sure bet the nematode population will grow and spread throughout.

Steddom began the study because there wasn’t a lot of field data on two of the labeled products. He could have tested the products on a number of different crops, but he chose pumpkins because they’re less labor intensive to harvest.

He tested nine different combinations of products on a site at the Texas AgriLife Research and Extension Center at Overton. He conducted the tests in a field that had a sandy loam soil and a high population density of root-knot nematodes.

One of the treatments tested was Vapam and Vydate, a chemical combination considered an industry standard. Another fumigant was Paladin, a relatively new product for which there wasn’t a lot of test data. The other two products were biological controls, one already on the market, another still in the experimental, testing stage.