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Poster: Biology & Disease Mgmt: Postharvest Pathology & Mycotoxins


Evaluation of sorghum germplasm for resistance to grain mold and mycotoxin contamination in the Mid-Atlantic
B. ACHARYA (1), N. McMaster (2), M. Balota (1), D. Schmale (2), H. Mehl (1); (1) Virginia Tech Tidewater AREC, U.S.A.; (2) Virginia Tech, U.S.A.

Grain sorghum production is increasing in the Mid-Atlantic region due to demand for locally sourced animal feed. Grain mold, caused by a complex of fungal species, infects grains, deteriorates quality, and reduces yield 30-100%. Some grain mold fungi produce mycotoxins that are toxic to both humans and animals, but little is known about the fungi and mycotoxins associated with sorghum grain in the Mid-Atlantic. The objective of this study was to evaluate sorghum germplasm for susceptibility to grain mold and mycotoxin contamination. Under natural field conditions, 375 genetically diverse sorghum accessions from more than 25 countries were evaluated for agronomic traits (panicle type and grain color), grain mold severity, and deoxynivalenol (DON) contamination. Mold severity ranged from 0-90%, and DON ranged from undetectable to10 ppm. Grain mold severity and DON concentrations varied among panicle types and grain colors (P<0.001). Overall, open panicles with dark colored grains had lower mold severity and DON concentrations than compact panicles with light colored grains. Given the potential for grain mold and DON contamination in sorghum grown in the Mid-Atlantic, future work will focus on characterization of the causal agents of grain mold and their associated mycotoxins and identification of sorghum germplasm and agronomic traits associated with reduced susceptibility to mold and mycotoxin contamination.