Control of leaf anthracnose of peach palm with fungicides: a valid strategy for seedling nurseries, but not for young plantations

ABSTRACT This work aimed to evaluate the efficacy of fungicides for controlling anthracnose (Colletotrichum gloeosporioides) on peach palm (Bactris gasipaesvar.gasipaes) seedlings in nursery beds and in newly planted peach palms in the field. The nursery experiment included two fungicide combinations: [thiophanate-methyl + chlorothalonil (TM + C) and pyraclostrobin + epoxiconazole (P + E)], three application intervals (7, 14, and 21 days), and an additional nontreated control. The two field experiments with newly planted peach palms tested the fungicide combinations TM + C at 15-day intervals for 12 months after transplanting, comparing to the control without fungicide application. The severity of anthracnose was assessed, and it was used for calculating the area under the disease progress curve (AUDPC). The fungicides TM + C and E + P applied at 7-days intervals were effective in the control of anthracnose in peach palm seedlings, resulting in the lowest severities and AUDPC. The fungicide TM + C reduced the maximum disease severity and AUDPC under field conditions. However, differences in the final severity of anthracnose and stem diameter were not significant compared to the control. Therefore, the use of fungicides for control of anthracnose in the field is not necessary.