Eleven peanut lines and the cultivar IAC-Tatu-ST, of the upright early maturing group (Arachis hypogae subsp. fastigiata, Waldron), were evaluated for pod yield, shelling percentage and average kernel weight in six field experiments carried out at the Ribeirão Preto and Pindorama Experiment Stations of Instituto Agronômico, State of São Paulo, Brazil, during the 1994/95, 1995/96 and 1996/97 growing seasons. Experiments used a split plot design where the main plots consisted of spraying and not spraying fungicides to control foliar diseases. Treated plots were periodically sprayed with 3.0 L.ha-1 of chlorothalonil to control early and late leafspots (Cercospora arachidicola and Cercosporidium personatum) and scab (Sphaceloma arachidis). Absence of disease control resulted in significant up to 60% yield reductions in all genotypes. Where diseases were controlled, the lines IAC 5, IAC 21, IAC 22 and IAC 81-12 showed the highest yield potential, reaching 5.000 kg.ha-1 in two experiments. Lines IAC 81-7 and IAC 88-1 presented superior relative performance along the environments with and without disease control. Diseases caused reductions in average kernel weight of up to 14%, especially in lines IAC 5, IAC 21 and IAC 22 whose kernel weights ranked highest. Differences in shelling percentage between genotypes were generally not significant. This character was also showed less influenced by foliar diseases.
peanut; Arachis hypogaea subsp.; fastigiata Waldron; inbred lines; yield potential; disease control
