Ask just about any farmer about recent improvements in crop yields and his top five list of contributing factors will include better varieties.
“Agricultural production has always advanced by improving seed,” says Jurg Blumenthal, Texas AgriLife Extension corn and grain sorghum specialist.
“We went from Indian corn to improved varieties and to hybrids after World War II,” Blumenthal said during the Blackland Income Growth (B.I.G.) Conference in Waco. “Then we went to genetically modified technology.”
He said those advances have improved yield potential and protected crops against losses from insects, diseases and environmental stresses. “More than 80 percent of our major crops are GMO,” he said, “but we still see controversy, especially in Europe and Japan with export limits. The consensus in the United States is that biotechnology benefits the environment.”
He said Texas has not been able to take advantage of all the yield enhancements from biotechnology that other areas, especially the Midwest, have enjoyed. “We’ve not been able to keep up with the grain yield. Yields have been stagnant, primarily because of drought." But technology to deal with environmental stresses may be coming.
He said research and breeding programs are identifying native strains and genetic opportunities to develop more drought tolerant corn varieties.
Blumenthal said three companies, Monsanto, Dow and Syngenta, are looking at “newer and stronger toxins and a broader spectrum of insect control” in biotech grains. He said target pests may include armyworms among others.
He also expects more stacked technologies with hybrids including herbicide tolerance and control of several insect pests. He said an eight-way stack may be available soon.
With new technology, he said, comes new management challenges. “Growers must be aware of refuge requirements with Bt corn,” he said. “They also need to know the different refuge requirements for underground pest refuge and above ground pests.”
He said some companies may soon offer “refuge in the bag,” with 2 percent to 5 percent of the seed non-biotech. “It’s not registered yet.” That technology would be for rootworm. “Growers would still need a 20 percent refuge for corn borer technology.”
Blumenthal said aflatoxin remains a serious threat to Texas corn production. “It’s hard to deal with. Researchers are breeding for resistance but that is far away.”
Biotechnology may provide some help. “In Bt versus non Bt trials in more advanced corn lines we should see less aflatoxin contamination in the Bt hybrids,” he said. “Traits prevent insect feeding and breaking kernels, where aflatoxin infects.”
He said drought tolerant corn offers promise with a 6 percent to 10 percent yield increase expected in the Western Great Plains. “I think the value will be better in Texas than for western Kansas or western Nebraska, areas that are more arid and with more evapotranspiration.”
Drought tolerant trials have identified two possibilities, native traits and transgenic lines.
“We have lines with the native trait in the pipeline. Something may be available in 2011. We’re five to seven years away from a transgenic hybrid.”
Blumenthal said the drought tolerance goal is to develop lines that lose less water per unit of biomass produced. He said biotech corn has already made some inroads. “These hybrids have better root systems so they extract more water and nutrients from the soil. Improving nitrogen use efficiency may offer a 5 percent to 10 percent yield boost. We get a yield increase by boosting key genes,” he said.
Technology also will improve herbicide tolerance for grain sorghum. “We’re using grain sorghum check-off dollars to support herbicide tolerance research."
Currently, efforts include both non-GMO and transgenic work. The non-GMO efforts include screening wild sorghums for natural tolerance to ALS and ACC herbicides.
Blumenthal said researchers are also looking at improved forage sorghums for both bioenergy production and forage. Brown mid-rib (BMR) sorghums show promise for both. The BMR lines are sorghum/Sudan hybrids and offer better digestibility, feed value and palatability. He said yield compares to corn.
“In grazing trials cattle preferred BMR to conventional sorghums and produced higher daily gains.”
Blumenthal said other research efforts include studies into grain and plant color. Improving grain for poultry use would “expand feeding opportunities.” He said the food market for grain sorghum is also expanding.
“It’s an exciting time for corn and grain sorghum, especially with better root systems for corn and new options for grain sorghum weed control.”