Interaction of dinitramine and dinoseb with Cylindrocladium crotalariae and the Cylindrocladium black rot (CBR) disease of peanut.1

Abstract

Abstract Axenic growth by Cylindrocladium crotalariae (Loos) Bell & Sobers in potato dextrose broth was suppressed significantly by dinoseb at 50 and 100 μg/mL, and Dyanapà (dinoseb + naptalam) at 100 μg/mL. High concentrations of either dinitramine or alachlor suppressed growth of only one of two C. crotalariae isolates tested. Benefin, diphenamid, vernolate, and 2,4 DB at rates up to 100 μg/mL failed to have similar effects on growth of either isolate. Dinitramine at rates up to 100 μg/g soil had no effect on survival of C. crotalariae microsclerotia (ms) in a Ruston or a Woodstown loamy fine sand. Dinoseb reduced ms populations significantly in Woodstown soil at 5, 10, 50 and 100 μg/g soil and in Ruston soil at rates of 50 and 100 μg/g soil. Soil type inoculum density, and herbicide dosage were demonstrated to be important interacting factors affecting CBR development in peanut. Greenhouse and field tests implicated dinitramine at 0.56 kg/ha and dinoseb at 1.68 kg/ha as herbicide treatments which can increase the severity of CBR in Florigiant peanut.