Navigation Links
More than just a hill of beans: Phaseolus genome lends insights into nitrogen fixation

"It doesn't take much to see that the problems of three little people doesn't add up to a hill of beans in this crazy world," Humphrey Bogart famously said in the movie Casablanca. For the farmers and breeders around the world growing the common bean, however, ensuring that there is an abundant supply of this legume is crucial, both for its importance in cropping systems to ensure plant vitality and for food security. Moreover, the U.S. Department of Energy Office of Science has targeted research into the common bean because of its importance in enhancing nitrogen use efficiency for sustainability of bioenergy crops, and for increasing plant resilience and productivity with fewer inputs, on marginal lands, and in the face of the changing climate and environment.

All plants require nitrogen to thrive, and nitrogen fixation is the process by which atmospheric nitrogen is converted into ammonia. However, many agricultural lands are deficient in nitrogen, leading farmers to rely on fertilizers to supply the needed nutrient for their crops. According to the U.S. Department of Agriculture, the United States imports more than half of the nitrogen used as fertilizer, a total of nearly 11 million tons in 2012. Kidney beans, navy beans, string beans and pinto beans are all varieties of the common bean, which ranks as the 10th most cultivated food crop worldwide. Legumes such as the common bean and soybean, however, can form symbiotic relationships with nitrogen-fixing bacteria. Understanding how such symbiotic relationships are formed and sustained is a crucial to improving agricultural practices as increasing crop yields are desired both for fuel and food production.

To this end, a team of researchers led by Scott Jackson of the University of Georgia, Dan Rokhsar of the U.S. Department of Energy Joint Genome Institute, Jeremy Schmutz of the DOE JGI and the HudsonAlpha Institute for Biotechnology and Phil McClean of North Dakota State University sequenced and analyzed the genome of the common bean, Phaseolus vulgaris. The project was supported by the U.S. Department of Energy and the National Institute of Food and Agriculture, U.S. Department of Agriculture, and the work was published online June 8, 2014 in the journal Nature Genetics.

"Unlocking the genetic make-up of the common bean is a tremendous achievement that will lead to future advances in feeding the world's growing population through improved crop production," said Sonny Ramaswamy, director of USDA's National Institute of Food and Agriculture. "While we have much to learn about the application of genomics in agriculture, this study is groundbreaking. I applaud the work of this team of scientists and look forward to their continued work in this important area."

For the study, the team sequenced and assembled a 473-million basepair genome of the common bean. Though it is thought to have originated in Mexico, the common bean was domesticated separately at two different geographic locations in Mesoamerica and the Andes, diverging from a common ancestral wild population more than 100,000 years ago. The team then compared sequences from pooled populations representing these regions, finding only a small fraction of shared genes. This indicated that different events had been involved in the domestication process at each location.

The team looked for regions associated with traits such as low diversity, flowering time, and nitrogen metabolism. They found dense clusters of genes related to disease resistance within the chromosomes. They also identified a handful of genes involved in moving nitrogen around. This information could be beneficial for farmers practicing the intercropping system known as milpa, wherein beans and maize or, occasionally, squash, are planted either simultaneously or else in a relay system where the beans follow maize. The practice ensures that the land can continue to produce high-yield crops without resorting to adding fertilizers or other artificial methods of providing nutrients to the soil.

The team then compared the high quality common bean genome against the sequence of its most economically important relative, soybean. They found evidence of synteny, in which a gene in one species is present in another. They also noted that the common bean's genome had evolved more rapidly than soybean's since they diverged from the last common ancestor nearly 20 million years ago.

"Improvement of common bean will require a more fundamental understanding of the genetic basis of how it responds to biotic and abiotic stresses," the team concluded. "These findings provide information on regions of the genome that have been intensely selected either during domestication or early improvement and thus provide targets for future crop improvement efforts."


Contact: David Gilbert
DOE/Joint Genome Institute

Related biology news :

1. Genome sequences show how lemurs fight infection
2. 3,000 rice genome sequences made publicly available on World Hunger Day
3. HIV can cut and paste in the human genome
4. Untangling whole genomes of individual species from a microbial mix
5. The first termite genome fills a gap in social inset genomics
6. Termite genome lays roadmap for greener control measures
7. Chinese scientists crack the genome of another diploid cotton Gossypium arboreum
8. Mapping the spider genome
9. Autism Genome Project delivers genetic discovery
10. Genome yields insights into golden eagle vision, smell
11. Trisomy 21: How an extra little chromosome throws the entire genome off balance
Post Your Comments:
(Date:11/9/2015)... JOSE, Calif. , Nov. 9, 2015  Synaptics ... human interface solutions, today announced broader entry into the ... vehicle-specific solutions that match the pace of consumer electronics ... and biometric sensors are ideal for the automotive industry ... vehicle. Europe , ...
(Date:10/29/2015)... RESTON, Va. , Oct. 29, 2015 ... announced today that it has released a new version ... Daon customers in North America ... gains. IdentityX v4.0 also includes a FIDO UAF ... customers are already preparing to activate FIDO features. These ...
(Date:10/27/2015)... , Oct. 27, 2015 In the present ... of concern for various industry verticals such as banking, ... to the growing demand for secure & simplified access ... ,sectors, such as hacking of bank accounts, misuse of ... equipment such as PC,s, laptops, and smartphones are expected ...
Breaking Biology News(10 mins):
(Date:11/25/2015)... ... 25, 2015 , ... Jessica Richman and Zachary Apte, founders ... initial angel funding process. Now, they are paying it forward to other microbiome ... investments in the microbiome space. In this, they join other successful entrepreneurs-turned-angels ...
(Date:11/24/2015)... 2015 Halozyme Therapeutics, Inc. (NASDAQ: HALO ) will ... New York on Wednesday, December 2 at 9:30 a.m. ... and CEO, will provide a corporate overview. th ... at 1:00 p.m. ET/10:00 a.m. PT . Jim Mazzola ... a corporate overview. --> th Annual Oppenheimer Healthcare ...
(Date:11/24/2015)... CITY , Nov. 24, 2015 /PRNewswire/ - Aeterna ... request of IIROC on behalf of the Toronto Stock ... news release there are no corporate developments that would ... --> --> About ... . --> Aeterna Zentaris is ...
(Date:11/24/2015)... ... ... The Academy of Model Aeronautics (AMA), led by its Executive Council, has officially ... to represent the First–Person View (FPV) racing community. , FPV racing has exploded in ... racing and several new model aviation pilots have joined the community because of their ...
Breaking Biology Technology: