This past growing season was challenging to say the least. What started out as an early crop saw a portion of the crop planted late after fields dried, which was followed by widespread lack of rain late season.
Although USDA's number does not show it (currently), this year's Mississippi soybean crop is probably better than last year as far as per acre yield. As always the crop has its ups and downs, but I feel the estimate of 35 bushels is low.
Although the northwest corner of the state experienced excessively dry weather most of the season, that was vastly different from the rest of the state. In contrast, the northeast corner of the state's crop benefited from rainfall off of Katrina.
Of all the major row crops grown in Mississippi, soybeans experienced the least amount of damage from the hurricanes. Yield losses statewide averaged about 5 to 10 percent. The southern area was harder hit, but statewide soybeans fared better than other crops.
Once the rains fell it was evident that many did not realize just how dry it had gotten. Growers in northwest Mississippi knew, but most could not believe how fast fields dried following Katrina and Rita. Since that time, dry weather has been the norm. It is obvious that physiology/growth was affected in numerous fields.
Trying to determine what has occurred in a field late in the season is usually affected by numerous factors. Problems observed in recent weeks are plants remaining green due to poor fruit set and stink bugs. In addition, wet weather early contributed to tap root abortion statewide. Once irrigation or rainfall occurred, the plants ability to recover was evident.
Late in the season many plants tried to compensate for poor fruit set by setting additional fruit, but time on the calendar was insufficient to allow for complete seed fill. Basically the plant was fooled into thinking that it could set more seed than it had set, but not enough time was on the clock.
Stink bugs continue to be the most prevalent pest statewide. We observed several fields where plants remained green due to lack of seed fill. It takes large numbers for an extended period of time to cause entire fields to remain green, but it occurs to some degree each year. Stink bugs are erratic, but if you had problem fields this year they will most probably be prime candidates next year.
As of late October the only soybean rust found in growers fields was in three fields very close to our sentinel plot in the Lucedale, Miss., area. Rust was found in two sentinel plots in Mississippi, one in Lucedale and the other in Poplarville. Once discovered, both sentinel plots were destroyed. We have looked extensively over the entire state and have not found any additional locations following the recent hurricanes. However, this has not been the case east of us.
It appears that soybeans are by far the best host for rust. Kudzu, although a host, is not as good a host. With kudzu, varying levels of susceptibility may exist. This is yet to be proven, but currently is being investigated.
This fall kudzu seed has been collected from over 40 different locations and sent to Moe Bondy in Ft. Dietrich, Md. He will attempt to answer these questions.
Sentinel plots proved to be quite valuable this year and will play a significant role in the future for early detection. They gave us a heads up, and we feel they will continue to prove effective. Problems were avoided this year and numerous questions were answered. Many questions still remain unanswered, but each season we will learn more.
However, the belief of many that rust would be widespread this past growing season and it was not and the fact that many appear anxious to study this new disease have made us aware that some have failed to look at the big picture regarding the U.S. soybean industry. I realize the presence of rust cannot be changed but attempts to slow its advancement are not on many individuals' radar screens today. Hopefully some dialog this winter can encourage others to look long term at the big picture (real world) versus short term.
Alan Blaine is the Mississippi Extension soybean specialist. e-mail: firstname.lastname@example.org