Mycelial growth, sporulation and germination of Colletotrichum abscissum and Colletotrichum gloeosporioides in aqueous extract of Osmundaria obtusiloba seaweed

• Grant number: 19/22167-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: February 01, 2020
• End date: December 31, 2021
• Field of knowledge: Agronomical Sciences - Agronomy - Plant Health
• Principal Investigator: Maria Candida de Godoy Gasparoto
• Grantee: Camila Lopes Miranda
• Host Institution: Universidade Estadual Paulista (UNESP). Campus de Registro. Registro , SP, Brazil

Abstract

Brazilian citriculture has the interference of many phytosanitary problems which cause significant damage to its production. Among the diseases that affect the culture, post-bloom fruit drop (PFD), caused by the fungi Colletotrichum abscissa and Colletotrichum gloeosporioides, can be highlighted. The main strategy to control the disease is the preventive application of fungicides every season, mainly, in commercial orchards where the disease has already been reported. In this way, unnecessary sprays are common in citrus areas most affected by the disease. Indiscriminate use of the few products currently registered to control of PFC can select resistant isolates of the pathogen, in addition to the possibility of environmental contamination. There is no PFD alternative control option to be applied in commercial orchards, becoming even more relevant the search for other methods of disease control. Among the alternative methods with the potential to control plant diseases, we highlight the application of extracts from marine macroalgae, especially those found in seas of the northern hemisphere of the planet. There are few studies with species of macroalgae present in tropical waters. The present study aims to evaluate in vitro control of the fungi Colletotrichum abscissa and Colletotrichum gloeosporioides under different concentrations of the aqueous extract of the Osmundaria obtusiloba macroalgae collected from the Brazilian coast.