Boron and Zinc Diminish Grey Necrosis Incidence by the Promotion of Desirable Microorganisms on Hazelnut Orchards

Abstract

In the southern hemisphere, the commercial production of hazelnut has increased in recent years, with a concomitant detection of new pathogens associated with plant production, so-called emerging infectious diseases (EIDs). Gray necrosis (GN) is a hazelnut disease that causes 30% of economic losses in Europe. In this sense, we recently reported GN as an EID in Chile, the main hazelnut producer in the southern hemisphere. Therefore, control strategies are urgently required to avoid disease dissemination. In this study, the effect of boron (B) and zinc (Zn) fertilization on the incidence of GN was determined. Additionally, the community composition of microorganisms via Dendrogram Gradient Gel Electrophoresis (DGGE) was evaluated, and bacteria from internal tissue (endophytic) were isolated to study their bio-control traits under greenhouse conditions. The microbial occurrence and biocontrol ability was evaluated using MALDI-TOF/TOF. According to the results, B and Zn promote beneficial bacteria which may be able to diminish symptoms associated with GN. Thus, beneficial microorganisms, applied in combination with micronutrients, could be synergistically applied in sustainable agriculture.