Evaluation of dry bean cultivars for resistance to Fusarium root rot under field and controlled conditions.
April 06, 2006
Carl A. Bradley, Extension Plant Pathologist
Jack Rasmussen, Chair, Plant Pathology Department
Ken Grafton, Director, North Dakota Ag. Experiment Station
North Dakota State University
To characterize Fusarium root rot resistance levels in a set of dry bean cultivars and to develop a greenhouse screening method that will predict the response of a cultivar to Fusarium root rot in the field.
Benefits to North Dakota and Minnesota Dry Bean Growers
Knowing the susceptibility or resistance level to Fusarium root rot in a dry bean cultivar can help growers choose which cultivar to grow based on known disease histories of fields. An accurate and efficient greenhouse method designed to screen dry bean lines for resistance to Fusarium root rot will aid in the development of resistant cultivars.
A set of eleven dry bean cultivars, representing different market classes, were evaluated for their level of resistance to Fusarium root rot in field (Fargo, ND and Park Rapids and Perham, MN) and greenhouse trials. In the greenhouse, three different screening methods were evaluated (layered-inoculum, spore inoculum, and paper-towel methods). Results from the field and greenhouse trials were compared to identify the most resistant cultivars and to identify the greenhouse screening method that had the best relationship to the field results.
The cultivars and breeding lines, Eclipse, Matterhorn, Maverick, Montcalm, Norstar, Othello, Red Hawk, Rojo Chiquito, T-39, Vax 3, and Vista were all evaluated in the greenhouse and field tests. In the greenhouse tests using all three screening methods, Rojo Chiquito had the greatest root rot severity rating, while Vax 3 had the least root rot severity rating. Of all the cultivars, Vax 3 had either the least or one of the least root rot severity ratings at all of the field trials. This suggests that Vax 3 may be a useful source of resistance to Fusarium root rot, and could be used to develop Fusarium root rot resistant dry bean cultivars adapted to the Northarvest region. All three greenhouse methods used to screen the cultivars for Fusarium rot resistance had good relationships with the field results. This suggests that any of these greenhouse screening methods could be used to identify dry bean cultivars or germplasm accessions with improved levels resistance to Fusarium root rot.