Many farmers throughout Alabama have been blessed this year with plenty of rainfall, but with that comes the specter of diseases, and soybeans and cotton both have been affected during the 2012 growing season.

For the most part, the state’s soybean crop looked good in late August, according to Auburn University Extension Soybean Specialist Dennis Delaney.

“Soybeans are looking pretty good, and we’ve got planting dates stretched out from early beans that are close to being harvested and late beans, including some that weren’t planted until Aug. 10, in south Alabama,” said Delaney during the recent East Alabama Crops Tour.

The annual tour took place a week prior to Hurricane Isaac making landfall in Louisiana. The storm was expected to bring heavy rainfall and wind to Alabama’s Gulf Coast region.

“A lot of our late beans have real good growth on them and have a lot of yield potential, but we’re just now getting into the critical growth stage as far as pod set and pod-fill, and that’s even more important than the vegetative stage. But anything that’s good for soybeans is also good for diseases,” says Delaney.

Sentinel plots planted throughout Alabama act as an early warning system for Asian Soybean Rust, he says.

“The disease was able to over-winter in Gulf Coast counties on kudzu and then move north as we got rainfall and as soybeans matured. We’ve got about 20 of these plots across the state, at experiment stations, and in farmer fields. We sample them about once each week as they begin blooming and become susceptible to rust,” says Delaney.

The plots are planted in various maturity dates so the rust can be monitored as it moves north.

The disease was found in early August in east-central Alabama, in Group III and Group IV soybeans, he says.

(For an earlier report on soybean rust in Alabama and recommended control procedures, click here).

At five locations in Alabama, researchers put in planting date tests, with soybeans being planted about every 10 days starting at the first part of June, says Delaney. The purpose of the study is to determine how yield decline corresponds with planting date.

“It was surprising last year that yield really didn’t drop off until after the fourth or fifth planting date on about the middle of July. That’s one year out of many, when we had a lot of late rain, which we don’t get every year.