<b>By TIM THORNBERRY<br>
Kentucky Correspondent</b> </p><p>

PRINCETON, Ky. — Soybean producers here have dodged the soybean rust bullet for the past couple of years – and with some luck, the same will be true for 2008.<br>

Researchers throughout the South are working to make sure this luck holds out. Recent research trials based in Tennessee, Georgia, Florida and Alabama via funding from the Southern Soybean Research Program (SSRP) have proven effective in containing the disease.<br>

Dr. Melvin Newman, professor in the Entomology and Plant Pathology Department at the University of Tennessee, said research was conducted in these states because of the known presence of spores. The study produced three significant findings that could give local producers a leg up in the event rust spores appear during a crucial time in production.<br>

“We found that early spraying was crucial to control rust,” he said. “A fungicide regiment with a triazole mix was the most effective, and two applications of fungicides were likely to be necessary.”
Concerning fungicides, the research noted the first application must be made at or before rust infection begins on the lower leaves. Based on the weather, the second application should be made 14-21 days later. Canopy penetration must be made to ensure good spray coverage.<br>

According to the 2007 study, the first application should be made between the R1 and R3 stage and should be a strobilurin fungicide if the risk of rust is only moderate.<br>

If the risk of rust is high, then a triazole fungicide must be used or a combination of a triazole plus a strobilurin. Strobilurins are more effective on other late-season diseases such as frogeye leaf spot, brown spot and anthracnose.<br>

If the threat of rust still exists, it is recommended by the study that the second application made between stages R3 and R5 be a triazole, such as Topguard, Domark, Larado or one of the tebuconazoles or a combination of triazole and a strobilurin. Most fungicide labels specify that applications be made prior to the R6 growth stage.<br>

Newman also said producers should really pay attention to the potential of rust moving in this year and the conditions that would be favorable for that to happen.<br>

“We shouldn’t forget about it this year. The last two years have been too dry for the infection to take place. The dry weather was a blessing in disguise,” he said.<br>

“Moisture is the key. If we have decent rain, it will be good for the soybeans and the rust, as well. I had one farmer tell me he’d rather fight the rust than the drought.”<br>

Newman also emphasized many farmers in these states are planting wheat because of the high prices, and that those producers will plant soybeans as a second crop after the wheat harvest. Couple that with early plantings further south, and the door opens for spores to make their way to this region at a crucial time.