Management of blossom malformation in mangoes with chemical control

T. Botha
Mango blossom malformation is a fungal disease caused by Fusarium spp. detrimental to the mango industry of South Africa, resulting in massive revenue losses each year. Darvas (1987) found that blossom malformation could be moderately controlled by stem injections of Fosetyl-Al and phosphorous acid (H3PO3). His work was taken a step further in the extensive testing of a product called LIMA, a phosphorous acid. In addition to Darvas' work, foliar treatments of LIMA were included into the trials to simplify the application method. Foliar sprays with LIMA repeated for a second season and applied twice a month during October, December, February, April and May resulted in a significant reduction in malformed flowers. Treatment applications during flowering did not show significant results and stem injections were not practical on small stem diameter mango trees. The seven foliar Lima sprays on the new flush and the nine monthly foliar sprays controlled blossom malformation on the subsequent flower the most effectively. Semi-commercial LIMA application trials revealed statistically significant treatment effects on four farms and in nine treatment blocks of a range of different blossom malformation susceptible mango cultivars.
Botha, T. (2017). Management of blossom malformation in mangoes with chemical control. Acta Hortic. 1183, 233-238
DOI: 10.17660/ActaHortic.2017.1183.33
Mangifera indica, blossom malformation, foliar spray, phosphorous acid

Acta Horticulturae