What is in this article?:
- Crop rotation still best long-term management strategy
- Plant for the market or for the rotation?
- A grower who plants the same crop in the same field over and over will have disease and pest problems in that field.
Pesticides are a costly but essential tool farmers use to control plant diseases and insects. Crop rotation continues to be a more reliable and economical management strategy.
"Rotations are the cornerstone in disease and nematode management," said Bob Kemerait, a plant pathologist with the University of Georgia campus in Tifton, Ga. "If a grower plants the same crop in the same field over and over, the pathogens, often molds and fungi, and nematodes become problematic."
If cotton is planted in the same field year after year, populations of the southern root-knot nematode are likely to reach damaging levels.
Peanuts are generally rotated with cotton crops as peanuts are not affected by the southern root-knot nematode and will reduce the damage cotton growers face in coming seasons.
Poor crop rotations can make managing plant diseases and parasites difficult and expensive. Even an expensive management program using nematicides and fungicides cannot fully replace an effective crop rotation, Kemerait said.
"One of the main reasons we rotate peanuts and cotton is they both attract a nematode, but it's a different nematode. One doesn't affect the other," said Glen Harris, a soil and fertility specialist with the UGA Tifton campus. "If you plant cotton after cotton after cotton, you build up a nematode problem. You throw peanuts in there, it knocks them back for at least a year."