LSU AgCenter research associate Luke Etheredge talks about research looking at the potential benefits of growing soybeans on fallow sugarcane fields. Etheredge gave the report during the LSU AgCenter’s sugarcane field day this week (July 20, 2005).

LSU AgCenter sugarcane researchers showcased new varieties at the sugarcane field day Wednesday (July 20, 2005).

LSU AgCenter Sugar Research Station resident coordinator Dr. Kenneth Gravois said there is a tremendous amount of interest in these new varieties.

The three varieties – HoCP 96-540, L 97-128 and Ho 95-988 – all have good yield potential and attractive characteristics, but the real interest stems from getting some of the sugarcane acreage away from the state’s dominant variety LCP 85-384.

That variety made up 91 percent of the Louisiana sugarcane crop last year.

"That’s not a good situation," Gravois said. "That’s a situation that puts all of our eggs in one basket.

"LCP 85-384 has been around for 12 years. While it’s been a good variety that growers are comfortable with, they are concerned by the amounts of rust disease showing up in their fields.

"LCP 85-384 was resistant to rust upon release to the industry in 1993, but Mother Nature is dynamic. She will not lay over and play dead," warned Gravois.

The expert said he suspects either the rust organism mutated or the characteristic was "selected out" of the variety over the years.

"Each year since 2000 we’ve seen increasing levels of rust, and that is very alarming to Louisiana sugarcane growers," Gravois said.

Rust is a foliar disease of sugarcane and will reduce the plants’ height and ultimately the yields.

Researchers also showcased two varieties for possible release in 2006 from the 1999 series. These two varieties have good yield potential and one, L 99-22

LSU AgCenter Sugar Research Station resident coordinator Dr. Kenneth Gravois talks to farmers about the potential for new sugarcane varieties. Gravois and others gave such reports during the LSU AgCenter’s sugarcane field day this week (July 20).

6, has the added benefit of insect resistance.

"It’s one of the first varieties eligible for commercial release in a number of years with resistance to the sugarcane borer," Gravois said.

The field day also highlighted research on alternate cropping systems. LSU AgCenter agronomist Dr. Jim Griffin and his research associate Luke Etheredge are looking at growing soybeans on fallow sugarcane fields.

"We’re looking at it from a weed control standpoint in the fallow system following sugarcane planting, and then we are also looking at sugarcane production from a yield standpoint following that system," explained Etheredge.

The research, which is in its third year, is comparing no- and low-till sugarcane systems, followed by a planting of soybeans. Etheredge is testing different row spacing for the soybeans.

The potential benefits of planting soybeans on fallow ground could be two-fold.

"Soybeans fix atmospheric nitrogen," said Etheredge. "If the research proves it to be a significant amount of nitrogen to impact the sugarcane crop following soybeans, that would show a benefit to planting soybeans."

The other benefit is weed control. Weeds such as nutsedge and Bermuda grass are problems in fallow fields.

"Once the soybean canopy forms over the top of the row there is significant shading, and we have shown with preliminary results how shade affects emergence and growth of nutsedge in certain situations resulting in reduced growth and proliferation," Etheredge said.

Reducing growth of weeds would also reduce the amount of herbicides growers would have to use on their fields. Etheredge said farmers using the system may be able to apply for federal grants with regards to best management practices and reducing the amount of topsoil run-off.

"It’s not going to fit in every situation or every farmer’s field, but it’s an option that each farmer would have to try to see if it works in his program," he said.

Etheredge also said more concrete results from these tests should be available in about a year.