New species and additional records of saprobic microfungi associated with Macadamia in China and Thailand and their lignocellulitic enzyme production

Abstract

Macadamia , a tropical and subtropical plant, is one of the most popular and nutritious nuts worldwide. Previous studies on macadamia-associated fungi have mainly focused on pathogenic and endophytic species, but the diversity and taxonomy of saprobic fungi associated with Macadamia remain poorly characterized. In this study, 18 fungal taxa associated with Macadamia spp. were collected from China and Thailand. Through morphological and multilocus phylogenetic analyses, five new species ( Dothiorella lignicola , Lasiodiplodia macadamiae , Palmiascoma macadamiae , Xylochrysis macadamiae , and X. yunnanensis ) are introduced, along with 13 previously known species across nine genera that are newly recorded from macadamia. In addition, 20 isolates representing these 18 taxa were evaluated for their potential to produce lignocellulolytic enzymes. Among the four enzymes evaluated, xylanase was the most frequently detected, followed by cellulase and mannanase, whereas laccase production was observed in only a limited number of isolates. These findings expand the known diversity of saprobic microfungi associated with macadamia and highlight their potential ecological roles in lignocellulose decomposition and possible applications in biotechnology.