Harvest is in full swing in southwest Louisiana and is about to begin in northeast Louisiana. The early rice yields in southwest Louisiana have been disappointing so far but are not unexpected considering the challenging season we have had this year.
The first key event that played a part in reducing rice yields this year was the late start and uneven emergence of the rice due to wet and cold soils.
This was exacerbated later when the often-wet soils prevented timely weed control and the application of nitrogen fertilizer on dry ground at the optimum growth stage.
After that, heavy rains soon caused water to overtop young rice. In some cases, water had to be drained so the stressed rice to recover.
Where all the water was drained, a lot of the nitrogen fertilizer was lost when the water was put back on the field due to nitrification/denitrification. If more N was not applied prior to reflooding then nitrogen may have become limiting at the most critical time for rice yield potential.
Rice diseases were low initially but the hurricane brought wind and rain at flowering, which caused wind damage and blanking of the grain. Secondary diseases, including sooty mold, moved in on the blanked grain.
High nighttime temperatures during grain fill and high humidity for the last part of the season (and even now) have been ideal for increased disease pressure. As such, bacterial panicle blight which has shown up quite a bit this year.
In addition, black kernel smut and false smut have shown up once again. The smut pressure this year in southwest Louisiana is greater than I have ever seen. Prior to the last few years, smuts generally were rare in the southern region and seldom did we need to apply a preventive propiconazole application during booting to protect us from the disease.
Going forward, if you have smut pressure this year you may want to consider treating for the disease next year or clouds of smut, like the false smut in the vide below, will become more common. (Click here to see the video).
All in all, we have a lot we can point our finger at to explain the low yields this year. We can also be thankful that Hurricane Barry did not bring the predicted 20 plus inches that was predicted for most of southwest Louisiana. This much rainfall would have overtopped our headed rice and we would have had a serious disaster on our hands.