DAMPING OFF CONTROL IN EUCALYPTUS NURSERIES BY FUNGICIDE SPRAYING

Abstract

The increment of the growth of tree conservation by means of official incentive, greatly intensified the planting of eucalyptus in Brazil, creating the necessity of producing seedlings in great quantities. Frequently the incidence of damping - off in the seedbed, in pre or post-emergence, affect the chronogram of planting, causing death of thousands of plantules. In the present experiment, it was attempted to determine the effect of seven fungicides, applied by spray at high volume, on the control of damping - off caused by Cylindroctadium sp. and Fusarium sp. in plantules of Eucalyptus saligna Sm. in the seedbeds. The experimental design used was that of random blocks with four (4) repetitions. The seeds were desinfected with dry Neantine at 0.3% and the seedbed was treated with methyl bromide (40ml/m² ), and afterwards innoculated with Cylindroctadium sp. and Fusarium sp. grown in substrate cornmeal-sand. It was observed that the most effective treatments in the control of damping — off were Arasan — 75 at 0.3%, Cupravit azul at 0.4% and Miltox at 0.35%, while the most phytotoxic was the Batasan at 0.15%. The plantules showed better vegetative aspect in the parts treated with Ferradol at 0.25%. The high density of seeding (50g/m²) coupled with the occurrence of humid and rainy weather seem to have contributed greatly to the high incidence of damping-off.