Pupunha (Bactris gasipaes H.B.K.) is a palm distributed in almost all the humid tropics at south America and Central America. The pupunha fruits are rich in starch, lipids and proteins. This crop presents a serious problem: after harveste the fruits are subject to the attack of black rot, caused by the fungus Thielaviopsis paradoxa. The fruit pulp becomes dark and smells as fermented In order to determine the spore concentration that induces black rot in pupunha, fruits with and without peduncle were inoculated with spore concentrations of 10 7 , 10 5 , 10 3 e 10' spores/ml. Fruits with peduncles were observed to require concentrations of 10 7 spores/ ml to attain 100% fruit infection. The fruits with seed showed greater sensibility to infection. In another trial the fungicides: Benomyl, Triadimefon, Zineb and Maneb, were tested in vitro at the concentrations of 25, 50, 75 e 100ppm in PDA medium (potato-Dextrose-Agar). Benomyl inhibited totally the growth of the fungus at all concentrations used. Triadimefon showed some efficiency at 100ppm, while Zineb and Maneb were inefficient at all concentrations tested.", 'en
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