As the 2018 rice crop progresses into the heading stage, farmers should be looking out for diseases and insects, but weed control should also remain a concern, LSU AgCenter scientists advised at the Acadia rice field day June 12.
AgCenter plant pathologist Don Groth has received a few reports of blast and sheath blight, although the diseases are usually more prevalent earlier in the growing season. “With moisture from rainfall, sheath blight will move very quickly once the rice gets into the reproductive stage,” said Groth. “The new Provisia variety is more susceptible to blast.” A new fungicide, Amistar Top, has activity against blast as well as sheath blight, and is labeled for second-crop applications.
AgCenter entomologist Blake Wilson warns growers that rice will be more susceptible to stink bugs in the first two weeks of heading. Pyrethroids are still effective against stink bugs in Louisiana, but farmers in Texas have reported reduced control, probably because the insecticide also is widely used on grain sorghum there . “A new product, Tenchu, has good stink bug control,” says Wilson.
AgCenter rice Extension specialist Dustin Harrell advises farmers growing a second crop should consider tank mixing the plant hormone gibberellic acid with a stink bug insecticide to boost the second-crop yield. “Nighttime temperatures will be critical in the next few weeks,” adds Harrell. “Higher-than-usual night temperatures will interfere with flowering and pollination, but the long-range forecast does not project above-average night temperatures.”
Sam Rustom, a weed science graduate student, says the rice herbicide, Loyant, is providing good results on cattails and other aquatic weeds. “Flooding rice on time is essential for good weed control. The longer you wait to establish the flood, the more you’re going to lose with grass and sedge control,” says Rustom.
AgCenter weed scientist Eric Webster is testing Loyant to see what varieties show injury from the herbicide. Early testing appears to show that hybrids are affected more than conventional varieties.
Ben McKnight, a post-doctoral weed scientist says benzobicyclon is proving to be a good aquatic weed herbicide, and it should be considered by rice farmers who also produce crawfish on fields that are flooded for most of the year. “The herbicide is good on pickerelweed and burrhead,” says McKnight. “It’s probably one of the best materials on duck salad I’ve ever seen.”
Matt Osterholt, a graduate student in weed science is testing RiceOne herbicide, and graduate student Conner Webster is testing different crop oils to evaluate antagonism of the Provisia herbicide when mixed with other herbicides.
AgCenter rice breeder Adam Famoso urged farmers to be patient with Provisia as the new variety will be followed with superior versions that have higher yield potential and better disease resistance. “The gene for Cercospora resistance has been identified, and that will help in the development of all rice varieties,” says Famoso.
AgCenter soybean specialist Todd Spivey says cold weather appears to have suppressed red-banded stink bugs. “Intensive scouting for diseases should be started for late-planted soybeans,” adds Spivey.
Louisiana Master Farmer Program representative Ron Levy, reports that Phase 1 training will be held at the LSU AgCenter’s H. Rouse Caffey Rice Research Station on June 26. Attendance at the Rice Research Station field event the following day will satisfy the Phase 2 requirement.
Two Other Rice Field Days
On July 16, the St. Landry Parish rice field day will be held at the Charlie Fontenot Farm near Palmetto, and the northeast Louisiana rice field day will be held at the Colvin Farm near Rayville on July 18.
Source: LSU AgCenter News LSUAgCenterNews@agcenter.lsu.edu