Response of eight sorghum cultivars inoculated with Fusarium thapsinum, Curvularia lunata, and a mixture of the two fungi

Field studies were conducted in 2000 and 2001 to investigate effects of two common grain mold fungi, Fusarium thapsinum, Curvularia lunata and a mixture of the two pathogens, on grain mold severity and seed germination in eight sorghum cultivars with different levels of vulnerability to grain mold. Significant effects due to cultivar, fungal treatment and their interaction were observed for grain mold severity (GMS) and for germination. Fungal treatments increased GMS and reduced seed germination in all cultivars. Sureno was the most resistant cultivar evaluated. All other cultivars exhibited susceptible reactions. The type of grain mold fungi present in the field influenced the level of GMS, since cultivars responded differently to inoculation with individual or multiple fungal species. Germination was significantly reduced by all fungal treatments. C. lunata had the most negative effect on germination in 2000 while F. thapsinum produced the most reduction in germination in 2001. These pathogens caused significant reductions in the germination rate, even though GMS ratings on inoculated particles were low. (C) 2003 Elsevier Science Ltd. All rights reserved.