Location: National Peanut Research LaboratoryTitle: Peanut germplasm screening for aflatoxin accumulation and genetic fingerprinting
|Arias De Ares, Renee|
|SEIJO, GUILLERMO - Instituto De Botánica Del Nordeste|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 6/19/2018
Publication Date: N/A
Interpretive Summary: Molecular tools accompanied of small sample size aflatoxin accumulation testing were developed for wild species of peanut. These tools will allow for the effective screening of peanut germplasm using a minimal amount of seed, in the search for aflatoxin resistance species/accessions.
Technical Abstract: Aflatoxin contamination in peanut seeds is still a serious problem for the industry and human health. There are no aflatoxin resistant cultivars, and given the narrow genetic background of cultivated peanuts, search for resistance is now focused on wild species. We adapted our aflatoxin accumulation testing method to the small-size seed of 20 wild peanut species, used only four seeds per accession, tested viability of each seed tested, and quantified the main four aflatoxins A1, A2, B1 and B2 for each seed using ultra-performance liquid chromatography (UPLC). In parallel, we fingerprinted each accession using 373 simple-sequence repeat (SSR) (288 novel) and Insertion-Deletion (InDel) markers to keep a genetic record of the accessions tested and proper identification within the germplasm collection. Levels of aflatoxin observed among the peanut species tested varied from 0 - 14000 ng.g-1 and 155 ng.g-1 of aflatoxin B1 and B2, respectively. 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. The best 88 markers, based on high fluorescence, good scorability and transferability, are reported. UPIC program identified a group of three high quality markers as sufficient to discriminate all 20 species tested. High quality markers with high UPLC scores and their corresponding significant hits on BLAST2GO are also reported. These tools can be used for the systematic search of aflatoxin resistant germplasm keeping record of the genetic fingerprinting of the accessions tested for breeding purpose.