EFFECT OF SOME SYSTEMIC DRUGS IN THE PREVENTIVE CONTROL OF THE MAL-DO-PANAMÁ (Fusarium oxysporum f.sp. cubense (EF.) SN. & H.) OF THE BANANA TREE (Musa sapientum L.)

Abstract

With the objective of studying the effect of some systemic drugs on the fungus, Fusarium oxysporim f. sp. cubense (Ef.) Sn. & H. , which attacks the rootstalk tissue of the cultivated ‘Maçã’ banana (Musa sapientum L.) an experiment was set up in virgin “cerrado” soil , which had been previously covered with natural vegetation. The effects of Benlate (benomyl) and Plantvax (oxamyl), both in doses of 0.1, 0.2, and 0.5%, as well as Mycostatin (nistatina) in doses of 0.02, 0.05, and 0.1%, and combination of Mycostatin plus soluble Neantina (chloride of metoxi-etil mercurio at 3.7%) in doses of 0.02 + 0.15%, 0.05 + 0.3%, and 0.1 + 0.5%, were tested by immersing the infected roostalks in the solutions for a ten-minute period. The rootstalks used had been naturally infected by the fungus. The experiment design used was randomized blocks with four (4) repetitions of twenty-six (26) treatments. Each parcel was composed of four (4) plants. The results observed in February of 1974 revealed an indiscriminate incidence of the ";Mal do Panamá” on the plants of all treatments, demonstrating that none of them was sufficiently effective in erradicating the pathogen established in the rootstalk tissues. It is suggested, because of root damage and the subsequent inadequate penetration by the fungicides, that this lack of absorption was responsible for the unsuccessful attempts at controlling the disease. It was concluded that the control of this disease is neither possible nor viable under the conditions in which the experiment was executed, using the above-mentioned method of fungicide application and preparation of the rootstalk. Changes in procedure are recommended for future experiments.