Insect Feeding Damage Lab

This week we looked at insect feeding on corn sorghum and soybeans.

The damage consisted of feeding on grain or leaves. Another type of damage that was observed was grain starting to rot probably caused from the disease entering where the insects have fed.



The feeding on corn consisted on kernels being fed on mostly towards the tops of the ears. There was some feeding through the husks into the ear. There was also signs of ear rots starting to show. These types of diseases are favored when there is a plant injury that could be caused by insect feeding.


The damage we saw on beans was feeding on the leaves. Some leaves had a few holes others were mostly gone with feeding. The feeding could be from worms or other insects with chewing mouth parts like a grasshopper.


The damage we saw on sorghum was feeding on the grain in the heads. Some heads had a few grains others were almost completely eaten. Damage could consist of worm feeding or even birds feeding on the grain. One big problem year after year in sorghum is corn earworm or headworms.


Estimating the damage is not an easy task. Two people may have completely different perspectives on how much the damage actually is. Another thing to consider is if the damage could affect yield. A little bit of leaf feeding would not be a big deal when related to yields. Getting a good feel for how much the damage will affect the yields is a good skill when consulting with producers. Another thing to look for is the insects themselves, though they might not be very evident even if they are there.

My results were pretty consistent in the soybeans and sorghum. My corn results were off more than in the other two crops.

This lab was not too tough. The tough part of this would be to perform in the field without having the correct answers via a scanner. Acquiring skills that lead you close to the right amount of damage would be a big help out in the field.

What's in the Bag

My experience with this lab on sorting insects from the field felt like a nice review for me. I could sort through the bag pretty easily and knew for the most part what each insect was.I found orders like lepidoptera, hemiptera, diptera, and coleoptera. I also sorted the insects into the way they feed or type of mouth-parts.

As you can see above are pictures of a grasshopper and a labeled drawing of parts of the insect.

There were many different mouth-parts in the bags of insects. I found chewing, piercing-sucking, and siphoning mouth-parts in my bags. I could see some limitations doing this lab in the field instead of the lab room. We would not have the access to the microscopes to get a better look at the mouth-parts of the insects, and if a person is out scouting alone they wouldn't have anyone to consult with about what they are seeing.

Test

This is a test. Entom 767.