ARTICLES
Authors: D. W. Gorbet , F. M. Shokes , L. F. Jackson
Three peanut (Arachis hypogaea L.) plant introductions (PI), eight breeding lines (BL), and the cultivar 'Florunner' were grown as subplot treatments in a randomized complete block with a split plot arrangement to evaluate their reaction to Cercospora arachidicola Hori and Cercosporidium personatum (Berk. and Curt.) Deighton in 1979 and 1980. Main plot treatments consisted of (1) no fungicide applications, (2) applications of chlorothalonil (500 g/l) on 10-day intervals and (3) 20-day intervals. Disease assessments as lesion counts were made at 20-day intervals beginning 50 days after planting. From leaf samples taken at the fourth leaf from a stem apex, C. personatum (CP) was the most prevalent pathogen both years. Differences among lines in susceptibility to CP were highly significant (P = 0.001) at 90, 110, and 130 days after planting. In unsprayed plots at 110 days, Florunner had the highest average CP lesion count at 51 lesions/leaflet compared to 21 for PI 261893. Fungicide treatment application significantly reduced CP at 110 and 130 days in both years. Also, defoliation and yield differences among lines were highly significant in both years. Five breeding lines produced pod yields exceeding 3400 kg/ha with no fungicide applied, compared to 2267 kg/ha for unsprayed Florunner. All breeding lines and Florunner showed at least some response to chlorothalonil. Pod yields had highly significant negative correlations with CP lesion counts and percent defoliation, ranging from 0.31 to 0.48.
Keywords: Arachis hypogaea, Cercospora arachidicola, Cercosporidium personatum, Groundnut, Leafspot Disease
How to Cite: Gorbet, D. , Shokes, F. & Jackson, L. (1982) “Control of Peanut Leafspot with a Combination of Resistance and Fungicide Treatment”, Peanut Science. 9(2). doi: https://doi.org/10.3146/