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Loss of function mutations in the <i>Waxy </i>(<i>Wx</i>) gene, encoding Granule Bound Starch Synthase (GBSS) that synthesizes amylose, results in starch granules containing mostly amylopectin. Grain with this trait has increased usability for feed, food and grain-based ethanol, due to altered starch properties. In sorghum, two classes of <i>waxy </i>(<i>wx</i>) alleles had been previously characterized for absence or presence of GBSS: <i>wx^a</i> (GBSS^-) and <i>wx^b </i>(GBSS⁺, with reduced activity). Field-grown grain of wild-type; <i>waxy</i>, GBSS^-; and <i>waxy</i>, GBSS⁺ Plant Introduction accessions, were screened for fungal infection. Overall, results showed that <i>waxy</i> grains were not more susceptible than wild-type. GBSS^- and wild-type grain had similar infection levels. However, height was a factor with <i>waxy</i>, GBSS⁺ lines: <i>wx^b </i>accessions, which were short, were more susceptible than tall <i>waxy </i>accessions, with an undescribed allele. In greenhouse experiments, grain from accessions and near-isogenic <i>wx^a</i>, <i>wx^b</i> and wild-type lines, were inoculated with <i>Alternaria </i>sp., <i>Fusarium thapsinum </i>and<i> Curvularia sorghina</i>, to analyze germination and seedling fitness. As a group, <i>waxy </i>lines were not more susceptible to grain pathogens than wild-type, supporting field evaluations. Amongst most <i>waxy </i>and wild-type lines, reduced emergence, survival and seedling weights were observed after <i>C. sorghina </i>and <i>F. thapsinum </i>inoculations. These results are valuable for developing <i>waxy</i> hybrids with resistance to grain-infecting fungi.