Mapping soybean genome promises designer plants
Scientists from Purdue University, the United States Department of Agriculture (USDA) and the Department of Energy teamed up to study one of the most important crop plants for seed protein, oil content and for its ability to fix atmospheric nitrogen.
Scott Jackson, agronomy professor at Purdue University told FoodNavigatorUSA.com: “The big value of mapping and sequencing the soybean genome is that it provides a toolkit for modifying its proteins and oils according to requirements.”
The mapping program, which took up to four years to complete, will allow scientists to identify which genes are responsible for particular plant characteristics, and then target specific genes to produce desired characteristics. That will allow beneficial genes to be moved into plant breeding programs.
Oils and proteins
“Soybean oil required for food processing and cooking is very different to that required for biofuels,” said Jackson. “This toolkit will allow oils and proteins to be tailored to specific end uses.” Knowing the genes behind the pathways of hydrogenated fats and fatty acids will allow scientists to modify them, he added.
In addition to modifications of direct benefit to the food industry, scientists will be able to improve soybean’s yield, resistance to pests and diseases, digestibility by animals and humans while cutting the contaminants present in the manure of soybean-fed hogs and poultry.
Randy Shoemaker, a research geneticist from the USDA's Agricultural Research Service at Iowa State University and co-researcher on the project said: "What used to take us literally years can take us weeks or months now. This is the entire genetic code in front of you."
Although the soybean has about 46,000 genes, between 70 to 80 percent are duplicates. That duplication could make it difficult to target the genes necessary to improve soybean characteristics such as seed size, oil content or yield.
“When soybeans were domesticated, they were selected for seed size and other traits, but there were a lot of potentially valuable genes left behind,” said Jackson. “There may be valuable genes associated with protein content or disease resistance in the stored lines that are not currently in the cultivated lines.”
Cheaper and quicker
That diversity should be explored by resequencing 20,000 soybean lines that are currently stored in the National Plant Germplasm System, he added. Also, having established the soybean genome for reference, the resequencing operation will be cheaper and quicker than it otherwise would have been.
The research is also expected to benefit related crops, such as pigeon peas and chick peas, which play an important role in the economies of some emerging countries.
The research was funded by the United Soybean Board, National Science Foundation, USDA and Department of Energy.
Soybean is now the first major crop legume species with a published complete draft genome sequence. The soybean sequencing study featured in the January 13 edition of Nature.