Hybrid Weaknesses Impact Pest Control

02:43PM Jul 15, 2019
Pest control
Seed selection drives defensive decisions for weeds, diseases and insects
( Darrell Smith and Lindsey Benne )

Hybrids are primarily chosen for the strengths they bring to each field. However, knowing their weaknesses is just as important.

Planning how to protect each hybrid begins by understanding each of your fields, says Farm Journal Field Agronomist Ken Ferrie:

  • Is the hybrid insect-traited? For which insects? Is the hybrid single-, double- or triple-traited?
  • Is the hybrid attractive to insects? “Some hybrids are more appealing to aphids, which are attracted by taste,” Ferrie explains. “Incidentally, this also applies to deer.”
  • To which diseases is the hybrid susceptible or resistant? “Some diseases, such as Goss’s wilt, might not be scored,” he says. “You might have to ask your seed rep to obtain information from the plant breeder. If you are fighting Goss’s wilt, you need answers.”
  • Is the hybrid sensitive to postemergence herbicides? “If weeds escape and you have to rescue the crop, decide whether the herbicide will do more damage than the weeds,” Ferrie says.

“After you collect this information, you’ll have a hit list of weaknesses you must manage around,” Ferrie says. “For example, if a hybrid is prone to early season soil-borne diseases (at germination and during early growth), you might protect it with a seed treatment or plan to plant the hybrid later, after the soil has warmed up.”

If a hybrid is susceptible to midseason diseases, from pollination on, watch weather patterns, scout and be ready to treat in a timely fashion.

“Some hybrids’ weakness is stalk quality,” Ferrie says. “Scout those fields before harvest, and harvest them first, if needed.”

Green snap can become a problem with high-yielding hybrids. “With these hybrids, make sure your crop insurance policy covers green snap,” Ferrie says.

Herbicide Sensitivity

With weeds, understand each hybrid’s genetic resistance. “Know which products a hybrid is sensitive to,” Ferrie says. “If it is sensitive to growth regulators, avoid growth-regulator herbicides. If you plant a refuge in a bag, you need to know the herbicide sensitivities of both hybrids. Sometimes this information is on the seed tag, and sometimes you have to ask your seed rep.”

Be aware of any hybrids that tend to be stressed by preplant or postemergence herbicides. If they are vulnerable, you might have to choose different products.

“Good records from past years are a great tool when making seed decisions,” Ferrie says. “If you don’t respect history, you are doomed to repeat it. If a hybrid had standability problems in a field three years ago, for example, be aware of it.”