# A New Species Bussabanomyces oryzae Isolated from Rice and Beneficial Application in Rice Seedling

## TL;DR

A new fungus called Bussabanomyces oryzae was discovered in rice roots and found to boost rice growth and stress resistance.

## Contribution

Identification and characterization of a new fungal species, Bussabanomyces oryzae, with beneficial effects on rice growth and stress resistance.

## Key findings

- Bussabanomyces oryzae promotes rice growth by increasing growth volume by 23% and fresh weight by 52%.
- The fungus enhances rice resistance to rice blast and improves seedling survival after transplantation.
- B. oryzae colonizes rice roots by invading epidermal, cortical, and vascular bundle cells.

## Abstract

Endophytes are a type of microorganism that lives in harmony with plants, playing a significant role in promoting the growth of the host and enhancing the host’s stress resistance. Understanding the ecological functions of root endophytic fungi and screening functional strains can effectively alleviate the stress conditions of crops. In this study, endophyte 1R13 was isolated from the roots of rice. Through morphological observation and five-gene combined phylogenetic analysis, it was identified as Bussabanomyces oryzae (B. oryzae), which was proposed as a new species, Bussabanomyces oryzae nov. The colonization pattern of B. oryzae was mainly through invasion of the rice roots, entering the epidermal cells and then the cortical cells, and finally reaching the vascular bundle cells. In the co-culture assays with rice, B. oryzae can promote the growth of rice, increasing its growth volume by approximately 23% and its fresh weight by 52%. Meanwhile, it could enhance the stress resistance of rice, mainly manifested as increasing the ability of rice leaves to resist rice blast and improving the survival rate of transplanted seedlings in the field.