ScienceDaily (Aug. 27, 2008) — The fungus Sclerotinia trifoliorum plagues legume crops worldwide. But chickpeas seem to have escaped its wrath, with the exception of Australia's crop. Now, that's no longer the case, report Agricultural Research Service (ARS) and collaborative university scientists.

During the 2005-06 chickpea growing season in central California, the team observed stem and crown rots reminiscent of Sclerotinia infection. But subtle irregularities in the symptoms led the researchers to believe their prime suspect—S. sclerotiorum, which infects more 400 plant species—had an accomplice, namely S. trifoliorum.

ARS research plant pathologist Weidong Chen led the team, which included Fred Muehlbauer (now retired) with the ARS Grain Legume Genetics Physiology Research Unit in Pullman, Wash., and University of California-Davis and Washington State University researchers.

They examined 10 Sclerotinia isolates from their collection from chickpea stems and subjected each to three identification criteria: growth rate, ascospore morphology and DNA markers indicative of S. trifoliorum. The team's analysis showed that S. trifoliorum isolates were slower-growing, displayed "ascospore dimorphism," which is the formation of two versions of the same spore type, and harbored a set of group I intron markers while S. sclerotiorum did not.

Chen suspects S. trifoliorum's occurrence on central California chickpeas stems from prior plantings of alfalfa—another legume host—and not an accidental introduction from Australia, the only continent where the fungus has previously been reported on chickpea. Identification of this new chickpea pathogen should aid in improving disease-management practices and developing resistant chickpea cultivars for farmers.

The research is part of the ARS National Sclerotinia Initiative. More information on this initiative is available at: http://www.whitemoldresearch.com

Journal reference:

1. Evans N. Njambere, Weidong Chen, Carol Frate, Bo-Ming Wu, Steve R. Temple, Fred J. Muehlbauer. Stem and Crown Rot of Chickpea in California Caused by Sclerotinia trifoliorum. Plant Disease, 2008; 92 (6): 917 DOI: 10.1094/PDIS-92-6-0917

Email or share this story:  

Chickpeas. (Credit: Photo courtesy of USDA/GIPSA)

Related Stories

First Of Crop Killer's Genome Sequence Available (July 17, 2002) — The first draft sequence of a worldwide crop-killing fungus genome has been completed under the joint National Science Foundation (NSF) and U.S. Department of Agriculture Microbial Genome Sequencing ...  > read more

Beneficial Fungal Strains Fight Harmful Ones In Corn (Apr. 1, 2005) — Nontoxic strains of a fungus have been developed by the Agricultural Research Service (ARS) to control toxins produced by a different strain of the same fungus in ...  > read more

Researchers Work To Combat Dangerous Aflatoxins (Sep. 21, 2000) — There's a fungus among us as the saying goes, and it's one researchers are working hard to eradicate. Recently, plant health scientists, gathered in New Orleans for their Annual Meeting, ...  > read more

Biological Control Could Be A "Green" Solution For Greenhouses (Mar. 2, 2000) — ‘Good' microbes that naturally inhibit a costly pathogenic fungus could help greenhouse growers control disease outbreaks. Tomato seeds treated with a beneficial strain of soilborne ...  > read more

Search ScienceDaily

Global Warming Equals Stronger Hurricanes