Location: Wheat, Sorghum and Forage ResearchTitle: Response of near isogenic sorghum lines, differing at the P locus for plant color, to grain mold and head smut fungi Author
Submitted to: American Phytopathological Society
Publication Type: Abstract Only
Publication Acceptance Date: 6/12/2013
Publication Date: 6/12/2013
Citation: Funnell-Harris, D.L., Prom, L.K., Sattler, S.E. 2013. Response of near isogenic sorghum lines, differing at the P locus for plant color, to grain mold and head smut fungi. Phytopathology 103 (Suppl. 3):S3.3. Interpretive Summary:
Technical Abstract: Leaves and stalks of many sorghum plants accumulate dark red or purple pigments upon wounding, while “tan” plants do not. Unpigmented “white” grain grown on tan plants is more desirable for food. The hypothesis tested was that these plant pigments protect grain from the panicle diseases grain mold and head smut. Near isogenic tan and purple plant color genotypes with white grain were planted at Lincoln and Ithaca, NE, and Corpus Christi, TX. Field grown grain was plated onto semiselective media to detect the presence of sorghum grain-molding genera Alternaria, Fusarium and Curvularia. Results indicated that more Fusarium and Curvularia spp. were recovered from grain grown at Corpus Christi than at Nebraska; however there was no indication that grain from purple plants was more resistant to the three fungal genera than grain from tan plants. Most fungi identified morphologically were Alternaria alternata. Molecular identification of Fusarium species using translation elongation factor 1-a gene sequences, showed that F. thapsinum and F. proliferatum infected grain at all three locations. At Corpus Christi, head smut disease incidence was assessed, which is caused by the fungus Sporisorium reilianum. Surprisingly, purple plants had significantly greater disease incidence than tan plants. We propose that the tan plant color lines, which are promising for development of food grade sorghums, are not more susceptible than pigmented lines to either grain mold or head smut.