Identification of novel sources of resistance to Pea enation mosaic virus in chickpea germplasm.

Authors: Larsen, Richard; Porter, Lyndon

Submitted to: Plant Pathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/22/2009
Publication Date: 2/1/2010
Citation: Larsen, R.C., Porter, L. 2010. Identification of novel sources of resistance to Pea enation mosaic virus in chickpea germplasm. Plant Pathology. 59:42–47

Interpretive Summary: Chickpeas, also known as garbonzo beans, are an important specialty crop in the Pacific Northwest region of the U.S. and in other parts of the world where they are regarded as a staple food crop. Of the many diseases that infect chickpea, Pea enation mosaic virus is one of the most destructive. Losses in epidemic years can be as high as 70%. Application of insecticides to control aphids that transmit the virus is environmentally unfriendly and also is generally ineffective. Currently, no resistance in chickpea has been identified for use in breeding programs. Therefore, the Cicer core collection consisting of 499 wild Plant Introduction (PI) accessions representing 26 countries and two chickpea phenotypes (desi and kabuli) was evaluated for resistant reactions to PEMV. Twenty-five genetically diverse accessions were classified as resistant to PEMV. Only two accession of the popular large seed kabuli types were found with resistance. Breeding programs will be able to introgress the resistant genes into advanced chickpea lines resulting in resistant cultivars that will improve yields even during years of high virus pressure. This is the first report of chickpea germplasm with resistance to PEMV.

Technical Abstract: Chickpea (Cicer arietinum) can be seriously affected by Pea enation mosaic virus (PEMV) in the Pacific Northwest of the USA and other areas of the world when viruliferous aphid populations are high. Use of pesticides to manage PEMV vector transmission is ineffective and PEMV-resistant chickpeas have not been identified. Therefore, the Cicer core collection consisting of 499 wild Plant Introduction (PI) accessions representing 26 countries and two chickpea phenotypes (desi and kabuli) was evaluated for resistant reactions to PEMV. Chickpea accessions were evaluated for resistance based on a 1 to 5 scale where 1 = symptomless and 5 = severe mosaic and stunting. Accessions with a mean disease severity (MDS) equal to or less than 2.9, and in which five or more individuals within the accession were symptomless were considered resistant to PEMV. Twenty-five accessions were classified as resistant, with MDS scores ranging from 1.3 to 2.9. The standard deviation of sixteen of the twenty-five resistant accessions was greater than 1.0, indicating a wide range of disease severity scores within an accession, most likely resulting from diversity within an accession due to collection methods. PI 450843 and PI 360609 (MDS = 1.4 and 2.9, respectively) were the only resistant kabuli type accessions identified. This is the first report of chickpea germplasm with resistance to PEMV.