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Soybeans Struggling After Heat, Drought
MISSISSIPPI STATE -- Recent rains across parts of the state breathed new life into some parched soybean fields, but much of the state's crop is still in critical need of moisture.
Storms have brought more than an inch of rain to parts of northeast and central Mississippi, while other areas, including most of the Delta, did not get any.
Dr. David Shaw, Mississippi Agricultural and Forestry Experiment Station weed scientist, said soybean yields will drop significantly if the rest of the crop does not get rain in seven to 10 days.
"The soybean plant begins to shut down in extremely dry weather to preserve life," Shaw said. "If it's beginning to go into the reproductive stage, you don't have viable pollination and seed production without moisture. That's when it takes the hit."
Not all soybeans are dry across the state. Patchy rains have supplied some fields with plenty of moisture while skipping other areas. Shaw said he has yet to see any dead soybeans, but many fields are extremely drought-stressed.
Non-irrigated and early maturing soybeans are being hardest hit. Irrigated fields are doing well, and later-maturing varieties are surviving better as they have not yet begun to bloom and produce.
"If we have a good rain, a lot of the crop will bounce back, but I don't think there's a doubt in anyone's mind that we will see some yield loss on soybeans that are not irrigated," Shaw said.
Eddie Harris, Delta area soybean agent with Mississippi State University's Extension Service, said 1 1/2 to 2 inches of soaking rain are needed to revive the soybean crop.
"If we get rain now, we could bounce back because we're not yet at the critical stage," Harris said. "But most of our beans are early maturing. They're blooming and starting to fill pods and need 1/4 inch of rain a day."
In addition to the lack of rain, the high temperatures and high humidity also have stressed the soybean crop. If the weather doesn't moderate and rain soon, Harris predicted a 20 to 30 percent soybean yield loss in the Delta.
Only about 30 percent of the Delta's soybeans are irrigated, Harris estimated, and those plants are maturing on schedule.
The good news in the otherwise bleak picture is the very low disease and insect pressures soybeans have seen this summer. A few fields have been sprayed for grasshoppers, and charcoal rot is possible when drought follows wet weather.
"The soybean crop had a good start, but dry weather is hurting us now," Harris said.