What is in this article?:
- Arizona Veg IPM: whiteflies on melons, lettuce pathogens, herbicides
- Soil-borne lettuce pathogens
- Dinitroanaline herbicides
- Whitefly numbers on fall melons are very high in Arizona’s Yuma Valley due largely to the crop landscape where melon fields are near or adjacent to cotton and alfalfa.
- The Arizona winter lettuce season includes the threat of diseases caused by soil-borne fungal pathogens.
- Dinitroanaline herbicides kill weeds pre-emergence by inhibiting cell division and elongation at the growing points of seedling roots.
By Barry Tickes, UA Area Agriculture Agent
The dinitroanaline herbicides are some of the oldest and most widely used. Sometimes called the “yellow herbicides,” these include Benefin (Balan), Trifluralin (Treflan), Pendimethalin (Prowl), Ethafluralin (Curbit), and Oryzalin (Surflan).
These herbicides kill weeds pre-emergence by inhibiting cell division (mitosis) and elongation at the growing points of seedling roots. The symptoms are “clubbed” or swollen root tips and the lack of lateral root development.
Although these all use the same mode of action and have similar chemical structures, you cannot assume that they all behave the same in the field or have the same effects on the diverse vegetable crops grown in the Yuma area.
Prowl (Pendimethalin) can be used on artichokes, carrots, tomatoes, peppers, and onions but not on lettuce or cole crops. Balan (Benefin) can only be used on lettuce.
Treflan (Trifluralin) can be used on cole crops, carrots, peppers, mustard greens, established asparagus, celery, chicory, established cucurbits, kale, okra, established onions, potatoes, radishes, and tomatoes but not on lettuce. Each acts differently in the soil and requires different cultural practices.
Prowl, for example, can be ‘water run,’ stays in suspension, and moves into the soil without mechanical incorporation. Balan nor Treflan do not stay in suspension when chemigated and often require mechanical incorporation.
Contact Tickes: (928) 580-9902 or firstname.lastname@example.org.
Question of the week – insect management
How quickly can an adult Bagrada bug kill broccoli seedlings?
A - 12 hours
B - 24 hours.