Aphids and nodules

Some interesting developments recently that bear watching for crop producers.
Researchers at the University of Illinois have discovered that some soybean aphids - known as Biotype 3 - can overcome current aphid-resistant varieties with the Rag1 and Rag2 resistance genes. They're different from the earlier discovered Biotype 2 aphids, which also have the ability to feed on some resistant material.
The researchers say these biotypes have existed in the population even before any resistant varieties were developed. In other words, there's enough natural variability in the soybean aphid population that efforts to breed an all-encompassing source of resistance into beans may prove difficult, if not futile.
Still on the aphid front, corn aphids are becoming more of an issue in the U.S. In fact, some agronomists are already suggesting that growers spray their crops at and possibly after silking because the little suckers - if they're present in high enough numbers - can do economic damage. In most cases that means aerial application.
Where did these aphids come from? OMAFRA field crops entomologist Tracey Baute believes it may have something to do with the increasing amount of fungicide being sprayed on the corn crop for "plant health" reasons. While these products are great at keeping plants healthier, longer, they also kill off beneficial fungi that just happen to keep aphids under control naturally.
So, growers may have some choices to make: spray an in-crop fungicide and perhaps be forced to also come in with an insecticide later, or limit fungicide spraying to only those situations where disease threatens yield.
Meanwhile, another U of Illinois scientist believes it's possible to "teach" corn plants to fix their own nitrogen.
Ag engineer Kaustubh Bhalerao says scientists have made progress by developing an amplifier inside bacteria, allowing the bacteria to sense the presence of an amino acid in their environment and produce a protein in response.
In other words, it may be possible to help nitrogen-fixing bacteria to communicate with the root systems of corn plants, similar to the way that soybean plants send messages to a bacterium telling it to colonize soy roots with nitrogen-fixing nodules.