EVALUATION OF AN AEROPONICS SYSTEM TO SCREEN MAIZE GENOTYPES FOR RESISTANCE TO FUSARIUM-GRAMINEARUM SEEDLING BLIGHT

A noncirculating aeroponics system was evaluated as a method for rapid screening of maize genotypes for resistance to Fusarium graminearum s eedling blight/root rot. The system allows for nondestructive, repetit ive sampling of seedlings for assessing disease progress and seedling growth. Shoot growth and root rot were assessed at 3-day intervals, an d final shoot and root dry weight were determined 15 days after inocul ation. The nine hybrids screened differed in severity of root rot as e arly as 6 days after inoculation, indicating differences in resistance to F. graminearum. Inoculation did not always significantly affect sh oot growth, root dry weight, or shoot dry weight, but differences in t hese agronomic traits were observed among hybrids. LH119 x LH51 and Pi oneer Brand 3379 showed the greatest resistance to root rot. Area unde r-disease progress curve and a critical stage of disease assessment (9 days after inoculation) gave similar rankings of hybrids for root rot resistance, indicating that a single disease assessment (versus multi ple assessments) may be adequate in screening for resistance with this aeroponics system.