Web Blotch Resistance in Arachis hypogaea¹

Seventeen genotypes of peanut, Arachis hypogaea L., consisting of Spanish, Runner, and Virginia market types were evaluated for resistance to web blotch caused by Phoma arachidicola Marasas, Pauer and Boerema in small plot field tests. Disease ratings were obtained by determining percentages of infected attached leaflets and abscinded leaflets. Marked differences in disease resistance were observed, and three levels of susceptibility were evident. Entries of the Virginia and Runner market types were generally more resistant to web blotch than the Spanish. Definitive yield and grade effects were not discernible, but indications were that yield and kernel size were affected.