Integrated control of rubber tree leaf blight association between genetic resistance and chemical control

Abstract

The chemical control efficiency of leaf blight (Microcyclus ulei) on rubber tree clones varying in partial resistance to this disease was studied. Under field conditions, the leaf flushes were weekly sprayed by one, two, three and four times using a misture of thiophanate methyl (0,125%) + triadimephon (0,025%) + methamidophós (0,06%). The first fungicide sprayings were initiated during the bud burst (A₂/A₃ leaf stage). The evaluation was carried out 30 days after the first spraying by determining the disease severity. The response to the leaf blight chemical control was proportional to the Hevea clones resistance level. The influence of each partial resistance component on the rubber tree response lo chemical control of leaf blight is discussed.