Exploratory profiling of microbial communities associated with tapping panel dryness in Hevea brasiliensis

Tapping Panel Dryness is a complex physiological disorder in Hevea brasiliensis that leads to the cessation of latex flow, causing significant economic loss, yet its underlying cause remains unclear. Anatomical investigation of bark samples collected from TPD-affected samples exhibited deformed latex vessels, blocked sieve tubes, and DNA-containing bodies within phloem elements. Metagenomic profiling indicated largely similar microbial composition and diversity between healthy and TPD-affected bark samples, except for the presence of low-abundance taxa such as phytoplasma only in affected samples. However, predicted metabolic pathways differed significantly between healthy and TPD samples. The combined anatomical, cytological, and molecular evidences in the current study supports the potential involvement of phytoplasma in the etiology of TPD.