Frances Gould, Schultz, Bruce
LSU AgCenter agronomist Dustin Harrell looks forward to the challenges of being Louisiana’s extension rice specialist.
“I’m following some highly respected people who have held that position in the past,” Harrell said.
Before Johnny Saichuk retired as rice specialist at the end of 2014, Harrell worked with him to learn more about the job.
Harrell will have verification fields in Calcasieu, Acadia, Vermilion and Concordia parishes.
To assist in Harrell’s agronomy research, Manoch Kongchum has moved from the Baton Rouge campus to the Rice Research Station and will be involved in all phases of research in the agronomy project.
In addition, research associates Jacob Fluitt and James Leonards will work with Kongchum. Two graduate students also work on projects that Harrell oversees.
In 2014, Harrell continued research into fertilizer products. He evaluated the effects of soil moisture on nitrogen use efficiency of preflood fertilization. He also evaluated urea fertilizer in dry, moist and flooded conditions.
“By far, the most efficient is when it is applied on dry ground and the field is flooded in a timely manner,” he said.
Nitrogen volatility potential is high when applied on dry soil and the flood is delayed for several days, he said. However, it can be minimized when a urease inhibitor such as Agrotain is used. When urea is applied into a standing flood, volatilization and nitrification/denitrification losses cannot be controlled even when Agrotain is used.
The least efficient is application into a flood, he said.
“By far, nitrogen on a dry soil is the most efficient in a continuously flooded system,” Harrell said, adding that he tested several fertilizer products.
He also studied potassium and phosphorus fertilizer application rates and timings. But, he said, the 2014 results showed no responses. It is likely that the current phosphorus and potassium fertilizer recommendations of 60 pounds per acre should be increased to 90 pounds.
Harrell also studied the use of salt as a dessicant applied before rice is harvested in anticipation of growing a ratoon crop. Salt makes harvest easier and quicker, he said, but the tops of the remaining plants must be cut quickly if a second crop will be attempted.
In fertility trials conducted at six locations, he looked at the nitrogen needs of new rice varieties and experimental lines. Harrell has new lab equipment for testing fertilizer products. “It will let us test nitrogen fertilizers and enhanced efficiency fertilizers in a controlled environment year-round,” he said. “And we’ll be able to look at different soil types from across the state.”
This article was published in the 2015 Louisiana Rice Research Board Report.