Year: 2005
Type: dissertation
Abstract: Peach tree brown rot, caused by Monilinia fructicola (Wint.) Honey can occur in flowers, branches, unripe fruit, harvest and post harvest fruit and accounts for damage in the world and Brazilian production. In Brazil, in spite of the importance of the disease, there is little research with different control methods in the field. Thus the objectives of this study were to assess the efficiency of the application of chemical active ingredients and biocontrol agents in the field, from flowering to harvest in two the study stages: treatment selection for brown rot control in the field and in vitro and application of the best treatments in commercial fields. For this the disease incidence was assessed in the flowers, unripe and ripe fruits in different treatments. The growth of the Trichothecium roseum antagonist and of the pathogen were assessed by submitting to different temperatures and T. roseum sensitivity to fungicides and Ca and K phosphytes were also assessed. The field experiments were carried out in 2002, 2003 and 2004. The BR-1 peach tree cultivar was used, which is late and highly susceptible to brown rot. In 2002 four antagonistic fungi were assessed: three T. roseum isolates (F1, F2 and F4), one Penicillium isolate (F9), the integrated peach production recommendation (PIP-PR), Ca and K phosphytes with captan; alternating fungicides, conventional farm treatment (PC) and control. In 2003 the experiments consisted of a control, fungicide altering, T. roseum, T. roseum alternated with captan + Ca and K phosphytes, T. roseum alternated with captan and T. roseum alternated with acibenzolar-S-methyl. In 2004 (PIP-PR), T. roseum, T. roseum alternated with captan + Ca and K phosphytes, T. roseum alternated with captan and the control were used. In the first experiment the T. roseum antagonist was selected as biological controller and in in vitro tests it was verified that temperatures between 20 and 25°C were ideal for the pathogen and also for the antagonist. The Ca and K phosphytes, and the fungicides captan and azoxystrobin and iminoctadine had less effect on inhibition than the antagonist, unlike iprodione, mancozeb and tebuconazole. In the 2003/04 field cycle, all the treatments assessed controlled brown rot compared to the control. In this cycle, only the treatments with fungicide controlled the disease in post harvest. In the 2004/05 cycle, the antagonist was efficient in controlling brown rot at flowering and the inclusion of Ca and K phosphytes, mixed with captan, improved disease control from fruit growth to post harvest.
Author: Luciene Martins Moreira
Language: Portuguese
Subfield: Plant Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: green
OpenAlex ID: W2350736773