Louisiana sugarcane farmers are finding a new weed in their fields, LSU AgCenter weed scientist Jim Griffin said at the annual AgCenter sugar field day on July 16.
Eastern black night shade is generally considered an annual weed that hasn’t been seen much in Louisiana, Griffin said. It’s related to tomatoes and potatoes and is shade-tolerant.
“In the last couple of years it’s become a problem,” said AgCenter weed scientist Al Orgeron.
Although eastern black night shade is considered an annual, it can survive a south Louisiana winter, Griffin said.
The weed seed is spread by birds. And although it hasn’t been a problem in recent years, weed scientists suspect the seeds have been dormant in the soil and appeared through a combination of appropriate weather cycles.
Eastern black night shade can be treated with herbicides with little effect if a grower waits too long, Orgeron said.
“Once this weed gets over about 6 inches tall, we can treat it, and it will begin to regrow in four weeks,” Orgeron said. “It’s kind of scary.”
The weed scientists also talked about the effectiveness of weed control in fallow fields, which is particularly important in sugarcane where the crop grows for three to four years after planting.
Although the new weed is troublesome, LSU AgCenter plant pathologist Jeff Hoy said a colder-than-normal winter kept brown rust disease in check in sugarcane fields.
“The freeze set the crop back, but it also held down brown rust,” Hoy said.
In other disease research, Hoy said, scientists are looking for resistant varieties in which the resistance lasts.
AgCenter entomologists have been monitoring the movement of the Mexican rice borer with pheromone traps, said AgCenter entomologist Julien Beuzelin.
“The AgCenter maintains 75 to 100 traps to pinpoint where they’re at,” Beuzelin said. It generally takes one to two years between the time an insect is found in a trap and when it’s present in fields.
AgCenter scientists have been monitoring the Mexican rice borer since it was discovered in Texas several years ago. It was first identified in Louisiana in 2008, said research associate Blake Wilson.
The Mexican rice borer as been moving east at about 15-20 miles a year, Wilson said. It was first identified in sugarcane in Calcasieu and Jefferson Davis parishes.
“We’re not sure how severe it’s going to be in Louisiana,” he said.
LSU AgCenter sugarcane specialist Kenneth Gravois talked about the basic sugarcane breeding program that’s a cooperative effort among the U.S. Department of Agriculture, the American Sugar Cane League and the AgCenter.
“We’re looking at how we’re going to sustain this industry for the next 90 years,” he said.
One of the challenges in sugarcane breeding is getting different plants to flower at the same time in order for cross pollination.
“We need to synchronize plants’ flowering to be able to cross wild clones with commercial varieties,” Gravois said.
AgCenter plant breeder Collins Kimbeng said scientists are looking for energy crops that can be produced in areas not suitable for food crops.
Research in north Louisiana is looking for “hidden treasures” in plants that have both cold tolerance and drought tolerance along with appropriate levels of sugars and fiber components that can be used in producing bioenergy.
Sonny Viator, resident coordinator at the AgCenter Iberia Research Station, said sweet sorghum has potential to be complementary with sugarcane to produce specialty chemicals such as butenol and aviation fuel.
AgCenter plant breeder Michael Pontif reviewed the current commercial sugarcane varieties that have been developed to improve tonnage and sugar per acre.
Representatives of the Center for GeoInformatics in the LSU College of Engineering had an information table at the field day to present information on their real-time GPS network.
“We provide a ‘black box’ for precision agriculture,” said Clifford Mugnier. The service is delivered through equipment dealers.
GPS systems for precision agriculture and similar applications, such as surveyors, require two devices – one mobile and one stationary. The LSU network provides the stationary device “to provide ‘corrections’ to the mobile device through a cell phone,” Mugnier said.
“We can provide accuracy to 1 to 2 inches,” he said.
The LSU system is the “best in the state,” said LSU AgCenter associate vice chancellor for plant and soil programs Rogers Leonard.
It also is one of the largest in the world, Mugnier said. In addition to 100 stations throughout Louisiana, the Center for GeoInformatics maintains tide gauges in the Gulf of Mexico for the National Geodetic Survey and National Oceana Survey in the National Oceanic and Atmospheric Administration.
And plans are in the works to establish stations at AgCenter research stations.