Location: National Peanut Research LaboratoryTitle: New tools to screen wild peanut species for aflatoxin accumulation and genetic fingerprinting
|Arias De Ares, Renee|
|PUPPALA, NAVEEN - New Mexico State University|
|DE BLASS, FRANCISCO - Instituto De Botánica Del Nordeste|
|Tallury, Shyamalrau - Shyam|
|GUILLERMO, SEIJO - Instituto De Botánica Del Nordeste|
Submitted to: BMC Plant Biology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/19/2018
Publication Date: 8/15/2018
Citation: Arias De Ares, R.S., Sobolev, V., Massa, A.N., Orner, V.A., Walk, T., Simpson, S.A., Ballard, L.L., Puppala, N., Scheffler, B.E., De Blass, F., Tallury, S.P., Guillermo, S. 2018. New tools to screen wild peanut species for aflatoxin accumulation and genetic fingerprinting. Biomed Central (BMC) Plant Biology. https://doi.org/10.1186/s12870-018-1355-9.
Interpretive Summary: Aflatoxin contamination in peanut seeds is still a serious problem for the industry and human health. No stable aflatoxin resistant cultivars have yet been produced, and given the narrow genetic background of cultivated peanuts, wild species became an important source of genetic diversity. Wild peanut seeds, however, are not abundant, thus, an effective method of screening for aflatoxin accumulation using minimal seeds is highly desirable. In addition, keeping record of genetic fingerprinting of each accession would be of tremendous value to use the combined information in breeding programs and identification of accessions within germplasm collections. In this study, we report a method of screening for aflatoxin accumulation for the small-size seeds of wild peanuts, and increased the reliability of results by incorporating screening for seed viability. Levels of aflatoxin observed among 20 wild peanut species varied from zero to 14000 ng.g-1 and 155 ng.g-1 of aflatoxin B1 and B2, respectively. We report screening of 373 molecular markers, including 288 novel SSRs, tested on 20 wild peanut species. Multivariate analysis by Neighbor-Joining, Principal Component Analysis and Principal Coordinate Analysis using 134 (36%) transferable markers, in general grouped the samples according to their reported genomes. Markers with UPIC scores as high as 16 (16 out of 20 species discriminated) are reported. The best 88 markers, high fluorescence, good scorability and transferability, are reported with their corresponding BLAST results against the sequenced genomes of wild species, and significant hits on BLAST2GO are also included. Sequences related to growth regulators, embryogenesis, signal transduction, transcription factors and apoptosis were among the best markers.
Technical Abstract: A new method to screen wild species of peanut for aflatoxin accumualtion is presented. The method uses minimal amount of seed, and is complemented with a test of viability of each seed. A total of 288 New microsatellite markers are reported, and the best combinations of these markers are made available to the public for the cost-effective genetic fingerprinting of germplasm collections.