Influence of Soil Fungal Communities on Soil Health in Relation to Yellowing Symptoms of Black Pepper (Piper nigrum L.) in Sarawak

Background and Aims Fungal communities are critically important for crop health and soil fertility. ITS amplicon sequencing has transformed soil fungal ecology by enabling high-resolution identification of fungal taxa, revealing extensive diversity and functional roles of soil fungal. However, our knowledge regarding how fungal community structure responds to healthy versus diseased black pepper crops is limited. This study aims to investigate the fungal community structure in soils from healthy and diseased black pepper crops, with a particular focus on the relationship between fungal abundance, diversity, and the symptoms exhibited by the plants. Methods We used high-throughput amplicon sequencing technology to comparatively analyze the fungal abundance, diversity, and community composition in soils from healthy black pepper crops versus those displaying yellowing symptoms. Results The findings revealed that black pepper plants with yellowing symptoms exhibited altered soil fungal abundance and significant variations in fungal diversity. Specifically, crops with yellowing symptoms showed an increased relative abundance of Fusarium , Purpureocillium , and Chaetomium , along with greater overall fungal diversity. Conversely, healthy crops had a higher abundance of beneficial fungi, such as Trichoderma and Humicola . Conclusions The analysis highlighted distinct shifts in trophic modes linked to disease progression and site location, emphasizing the dynamic interactions between plants and soil microbes. This study suggests the potential for targeted interventions, such as the use of biocontrol agents or soil amendments, to promote beneficial fungi while suppressing pathogenic taxa, ultimately improving soil quality and plant health.