Chemical Control of Seedborne Fungi of Sorghum and Their Association with Seed Quality and Germination in Puerto Rico. P. R. Hepperly, Assistant Professor of Plant Pathology, Department of Crop Protection, University of Puerto Rico, Mayaguez 00708. C. Feliciano, Former Graduate Fellow, Department of Crop Protection, University of Puerto Rico, Mayaguez 00708, and A. Sotomayor, Research Geneticist, Mayaguez Institute of Tropical Agriculture, Agricultural Research Service, U.S. Department of Agriculture, Mayaguez. Plant Dis. 66:902-904. Accepted for publication 19 January 1982. Copyright 1982 American Phytopathological Society. DOI: 10.1094/PD-66-902.

Fusarium (mostly F. moniliforme), Curvularia (mostly C. lunata), and Alternaria sp. were the most commonly isolated fungi from Capitan sorghum (Sorghum bicolor) seeds produced under humid tropical conditions in Mayaguez, PR. Seedborne incidences of F. moniliforme and C. lunata were negatively correlated (P = 0.01) with seed germination (r = –0.97 and –0.63, respectively) and positively correlated (P = 0.01) with visible seed damage (r = 0.92 and 0.84, respectively). Seedborne incidence of Alternaria sp. was not associated with germination or seed damage (r = –0.26 and –0.28, respectively). Weekly applications of benomyl plus captan (0.5 + 0.5 kg/ha) from boot stage to physiologic maturity completely controlled F. moniliforme and significantly (P = 0.01) reduced C. lunata. Besides reducing fungal infections, fungicide applications increased seed yield, 100-seed weight, and germination.

Keyword(s):