pnut pnut Peanut Science 0095-3679 0095-3679 American Peanut Research and Education Society 10.3146/i0095-3679-10-2-5 Articles Peanut Yield, Market Quality and Value Reductions Due to Cylindrocladium Black Rot1,2 J. K. Pataky , M. K. Beute , J. C. Wynne , and G. A. Carlson 3 Graduate Research Assistant and Professor, Department of Plant Pathology; Associate Professor, Department of Crop Science; and Professor, Department of Economics; North Carolina State University, Raleigh 27650. Present address of the senior author: Department of Plant Pathology, University of Illinois, Urbana 61801

1Paper No. 8794 of the Journal Series of the North Carolina Agricultural Research Service, Raleigh, NC 27650.

2Use of Trade names in this publication does not imply endorsement by the N. C. Agricultural Research Service of the products named, nor criticism of similar ones not mentioned.

 7 1983 10 2 62 66 3 8 1983 American Peanut Research and Education Society 1983 American Peanut Research and Education Society Abstract

The effects of Cylindrocladium black rot (CBR) of peanut (Arachis hypogaea L.) on yield, market quality and monetary value of the peanut crop were determined for Florigiant, NC 8C and two advanced generation CBR-resistant breeding lines. Percentage extra large kernels (ELK) and fancy size pods (FS) were decreased by CBR. The reduction of ELK has a minor effect on value. The reduction of FS had no effect on value. Reduction of value due to CBR was primarily the result of lower peanut yields. A highly significant proportion of the variation in yield and value was explained by regressions of yield and value on % CBR incidence measured approximately 1 wk before digging. Yield losses ranged from 250 to 450 kg/ha and value reductions for Florigiant and NC 8C were from $170 to $190/ha in 1980 and 1981 and from $270 to $290/ha in 1982 for each 10% CBR incidence. The relationships among CBR and yield, quality and value were similar for NC 8C and Florigiant. Therefore, NC 8C should sustain lower losses due to CBR than Florigiant because NC 8C is moderatley CBR-resistant.

 Key Words Cylindrocladium crotalariae; , disease loss assessment; , epidemiology