Scientists identify genetic resistance to rice sheath blight

May 04, 2010

Agricultural Research Service (ARS) scientists have identified sources of genetic resistance to sheath blight, a major disease affecting rice production worldwide.

Sheath blight, caused by the fungus Rhizoctonia solani, is a major disease of rice that affects yield and grain quality. Geneticist Anna McClung, director of the ARS Dale Bumpers National Rice Research Center in Stuttgart, Ark., and research leader of the Rice Research Unit in Beaumont, Texas, heads a group of ARS scientists examining the in search of genetic resistance to this serious disease.

Plant pathologist Yulin Jia and colleagues at Stuttgart had a breakthrough in their sheath blight mapping efforts when they identified and confirmed qShB9-2, the first genetic region they have found to have a major effect on controlling the disease.

In a related project, geneticist Georgia Eizenga at Stuttgart screened 73 wild rice species for signs of sheath blight resistance. Seven accessions showed promise, and Eizenga's team has crossed some of those accessions with domestic varieties to create new, resistant germplasm.

The Stuttgart scientists have also developed a standardized screening technique to help quickly and accurately detect sheath blight in seedlings. Called the "microchamber method," this technique uses 2-liter or 3-liter plastic bottles to create a humidity chamber to promote disease development. This allows the researchers to measure seedlings' disease reaction in just seven days, accelerating the process of identifying novel, resistant sources from cultivated and wild relatives of rice.

Meanwhile, in Beaumont, geneticist Shannon Pinson has been studying gene-mapping populations from recombinant inbred lines (RILs) of domestic rice cultivar "Lemont" and Chinese cultivar "TeQing." She found 18 in these RILs with genes that can help plants resist damage from sheath blight, including the qShB9-2 genetic region confirmed by Jia. Two of the regions have shown a large, measurable effect on sheath blight resistance.

The scientists' studies can be found in Plant Disease, Molecular Genetics and Genomics, Frontiers of Agriculture in China, Theoretical Applied Genetics, Crop Science, Phytopathology and the Journal of Plant Registrations.

Explore further: Research in rodents suggests potential for 'in body' muscle regeneration

Provided by United States Department of Agriculture

5 /5 (2 votes)
add to favorites email to friend print save as pdf

Related Stories

Genomics Research Focuses on Rice Variety Improvement

Jul 01, 2008

Crop varieties can be improved through the study of genomics without creating genetically transformed varieties. That is the mission of a multistate research project led by the University of Arkansas System’s Division of ...

Transplanted corn gene protects rice

Oct 18, 2005

Kansas State University scientists say they've demonstrated resistance to bacterial streak disease in maize can be transferred to rice.

Diverse wheat tapped for antifungal genes

Apr 01, 2010

Asian wheat may offer novel genes for shoring up the defenses of U.S. varieties against Fusarium graminearum fungi that cause Fusarium head blight (FHB) disease.

Gene's past could improve the future of rice

Jan 23, 2009

(PhysOrg.com) -- In an effort to improve rice varieties, a Purdue University researcher was part of a team that traced the evolutionary history of domesticated rice by using a process that focuses on one gene.

Recommended for you

Sorghum and biodiversity

10 hours ago

It is difficult to distinguish the human impact on the effects of natural factors on the evolution of crop plants. A Franco-Kenyan research team has managed to do just that for sorghum, one of the main cereals ...

Going to extremes for enzymes

Sep 01, 2014

In the age-old nature versus nurture debate, Douglas Clark, a faculty scientist with Berkeley Lab and the University of California (UC) Berkeley, is not taking sides. In the search for enzymes that can break ...

User comments : 0