Skip to main content

Scouting for Armyworm and Fusarium Head Blight in Wheat

Me scouting wheat for signs of pest and disease damage.

Armyworm, armyworm, armyworm! The past few weeks nothing has been a larger concern to wheat and field crop growers than the army worm infestation in Western New York. Several farmers have been plagued by this relentless pest, and concerns are on the rise as to what the economic damage has been to growers this year. The armyworm is primarily a pest of grasses, small grain crops and corn. The insect will also attack alfalfa, beans, clover, flax, millet, and sugar beets. Feeding and movement occur at night or on cloudy days. During the daytime, armyworms hide under vegetation, loose soil or in soil cracks. Caterpillars consume more and more vegetation as they grow. Since they feed at night and hide during the daytime, armyworms often cause considerable damage before being discovered making them a dangerous pest for growers.

Here army worms are feeding on the head of wheat plants.

 

To the left you can see the damage that armyworms can do to the wheat plants. If you look closely the leafs have been stripped from the plants and the damage is now being done to the heads of the wheat.

The next major concern is the possibility of another generation of armyworm growing during the growing season. The life cycle of the army worm is now at the pupate stage. The larvae move under litter and soil clods, or burrow 2 to 3 inches into the soil, where they make small cells in the soil and pupate. About two weeks later, moths emerge from pupal cases, mate, and lay eggs for the next generation.  A great deal of concern is on the rise as to weather there will be a second plague if these pest or not, only time will tell.

I have been visiting several farms in the Western New York region not only scouting for armyworm, but for wheat disease as well, focusing mainly on  Fusarium Head Blight and Rust. Fusarium head blight or head scab is caused by the fungus Fusarium graminearum. The disease causes tremendous losses by reducing grain yield and quality and is a growing concern for wheat producers in Western New York. Symptomology of head blight in wheat  is any part or all of the head may appear bleached. The partly white and partly green heads are diagnostic for the disease in wheat.

Here is an example of head bleaching due to Fusarium Head Blight.

The fungus also may infect the stem  immediately below the head, causing a brown – purplish discoloration of the stem tissue. Additional indications of head blight infection are pink to salmon-orange spore masses of the fungus often seen on the infected spikelets and glumes during prolonged wet weather.

There is no simple cure for Fusarium Head Blight in producers fields so a combination of treatments is suggested. Seed treatment and the use of high-quality seed will help reduce seedling blight due to infected seed but will not protect against subsequent head blight.  The main precautions for growers to consider while aiming to prevent against head blight are seed treatment, tillage, crop rotation, planting date, and resistance.

Here you can see the salmon colored fungal spores associated with Fusarium Head Blight.

Although there is no wheat variety that has true resistance to the head blight, there are certain varieties that show moderate resistance to the blight that are recommended for growers use.

With wheat reaching the date of harvest, my scouting skills will be relocated to the soybean fields of Western New York! Stay tuned for my next scouting adventure!

 

 

Speak Your Mind

*

Skip to toolbar