Fusarium spp. contribute to reduced pasture persistence in Aotearoa New Zealand

Conference abstract: Fusarium spp. are widely distributed soil-borne fungi known for their devastating effects on global agroecosystems as plant pathogens. In Aotearoa New Zealand (AoNZ), the persistence of sown pastures has been declining in northern regions, with implications for farming profitability. Concurrently, soil-borne disease has been identified as contributing to reduced plant growth, but the causal agents remain unidentified; research in pasture plant pathology remains limited. This study investigates the distribution and abundance of Fusarium spp. in pastures and their role in soil-borne disease. We aim to understand the host-pathogen relationship in a microbial community context through a combination of in vitro and in planta pathogenicity assays, coupled with 16S and ITS amplicon sequencing. Preliminary results from pathogenicity assays indicate that Fusarium spp. significantly hinder Lolium perenne (perennial ryegrass) growth, suggesting a role in pasture soil-borne disease pressure. Furthermore, analysis of soil amplicon sequencing and plant growth pasteurisation assays are providing further insights into conducive environments supporting this host-pathogen relationship. Combined, these data will improve knowledge of microbial effects on pasture growth, contributing to future management strategies for combating plant pathogens in AoNZ pastures and addressing the economic challenges associated with declining pasture persistence. Our work is a significant step to improving knowledge of plant pathogens affecting pastures in AoNZ.