GENETIC-ANALYSIS OF RESISTANCE TO FUSARIUM-SOLANI IN SOYBEAN

Sudden death syndrome caused by highly pathogenic strains of Fusarium solani (Mart.) Appel & Wollenw. emend. Snyd. & Hans., can cause severe foliar necrosis and yield reduction in soybean [Glycine mar (L.) Merr .]. The soybean cultivar Ripley is resistant to foliar disease symptom s caused by F. solani. To determine the genetic control for F. solani resistance in Ripley, Ripley was crossed reciprocally to Spencer, a cu ltivar that develops severe foliar chlorosis and necrosis when infecte d with F. solani. Progeny from these crosses were evaluated in the gre enhouse for reaction to F. solani using an infested-oat inoculation te chnique. Reaction to F. solani in segregating F2 and F3 generations in dicated that the ability for Ripley to resist foliar disease symptoms caused by F. solani is conditioned by a single dominant nuclear gene ( Rfs).