pnut pnut Peanut Science 0095-3679 0095-3679 American Peanut Research and Education Society 10.3146/i0095-3679-10-2-16 Articles Interaction of dinitramine and dinoseb with Cylindrocladium crotalariae and the Cylindrocladium black rot (CBR) disease of peanut.1 J. A. Barron and P. M. Phipps 2 Former Graduate Research Assistant, Department of Plant Pathology and Physiology; and Associate Professor of Plant Pathology, Tidewater Research and Continuing Education Center, Suffolk, VA 23437. Senior author is currently Product Development Associate, Monsanto Agric. Prod. Co., 11550 N. Meridan St., Carmel, IN 46032

1Contribution of the Tidewater Research and Continuing Education Center and the Department of Plant Pathology and Physiology, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061. This research was supported in part by USDA cooperative agreement 12-14-7001-855 and represents a portion of the senior author's Ph.D. dissertation. Mention of a trademark or proprietary product does not constitute a guarantee or warranty of the product by Virginia Polytechnic Institute and State University and does not imply its approval to the exclusion of other products that may be suitable.

 7 1983 10 2 101 106 3 12 1983 American Peanut Research and Education Society 1983 American Peanut Research and Education Society 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.

 Key Words Arachis hypogaea L; , Calonectria crotalariae (Loos) Bell & Sobers; , herbicides; , microsclerotia; , soil type