?????:????,???????????! � ??? News&Market |????

?????:????,???????????! � ??? News&Market |????

Comments

Post a Comment

Popular posts from this blog

Soldier Beetles, Not Blister Beetles

Image
A Lubbock County grower came to my office this morning with a bottle that held 20 or so beetles he collected from the edge of a field. His concern was that they were blister beetles, and I was pleased to be able to say that they were soldier beetles. However, given the high numbers he described in the field, soldier beetles must be very abundant this year. Photo credits: Ed Bynum and Pat Porter There is some resemblance, but these beetles are different enough to be separated on sight. One problem though is that he showed me a web page that incorrectly identified soldier beetles as blister beetles; the internet strikes again. Texas growers can always send us a photo of an insect if they want an identification. Soldier beetles, insect Family Cantharidae, are predacious on other insects as both adults and larvae. Blister beetle larvae, insect Family Meloidae, are predacious on grasshopper eggs and the larvae of wild bees. When disturbed, blister beetles exude hemolymph (the insect versio...
Read more

Assessing the Value of Bt Corn When Insects Are Resistant - Part I: Corn Rootworm

Image
We are entering a time when insects have become resistant to many of the Bt toxins in our GMO corn and cotton. This is the first in a series of articles where I will discuss what this might mean in terms of crop damage and the value of the Bt technologies.  To start the series, I want to make it clear that Bt crops are more than just insect protection; they are herbicide tolerance, cold tolerance, and improved genetics for yield, drought and disease tolerance. These other virtues remain even when the insect control fails, although reduced insect control clearly can affect some of them, like yield potential and drought tolerance.  Back in the early days of Bt crops, seed companies defined and charged a "technology fee" that was added to seed cost; growers knew what they were paying for insect protection. Those days are long gone, for various reasons, and now the seed cost is what it is and there is no way to know how much is being paid for the Bt traits.  While we don't kn...
Read more

Fumonisin Levels and Insect Damage in Corn

Image
I am not smart enough to be a Plant Pathologist, and in fact had two courses in it in college and still don't understand it. The classic "disease triangle" taught in pathology says that disease occurs when there is a pathogen, susceptible host and conducive environment. This year we seem to have had a happy triangle for Fusarium species, the causative agents of fumonisins. Not much is known locally about how these fungi interact with our corn, but it is thought that drought stress followed by warm, wet weather, especially at flowering, favor the fungi. Being just an entomologist, I tend to think there is a baseline risk for significant fungal infection based on the susceptibility of the host (hybrid genetics) and environmental conditions. Without insects in the system there will be a given level of fungal growth and fumonisin creation. In my simplistic entomologist's picture, the baseline level is what it is and can vary from year to year, but insect damage can add to...
Read more