Chemical Control of Mango Blossom Diseases and the Effect on Fruit Set and Yield. J. H. Lonsdale, Plant Pathologist, Merensky Technological Services, Westfalia Estate, P.O. Box 14, Duiwelskloof, 0835, South Africa. J. M. Kotzé, Head of Department, Department of Microbiology and Plant Pathology, University of Pretoria, Pretoria, 0002, South Africa. Plant Dis. 77:558-562. Accepted for publication 16 December 1992. Copyright 1993 The American Phytopathological Society. DOI: 10.1094/PD-77-0558.

Blossom sprays with iprodione, chinomethionat, prochloraz manganese chloride, triadimenol, copper oxychloride, mancozeb, flusilazol, calcium polysulfide, and pyrazophos, applied fort-nightly, were evaluated over two seasons (1989–1991) for the control of powdery mildew (Oidium mangiferae), blight (Nattrassia mangiferae), and blossom spot (Alternaria alternata and Colleto-trichum gloeosporioides) of mango (Mangifera indica). Blossom sprays with the systemic fungicides flusilazol or pyrazophos resulted in significantly better disease control and consistently higher fruit set and yield than nontreated controls.