AUTHOR=Zheng Li , Zhao Jie , Liang Xiaofei , Zhan Gangming , Jiang Shuchang , Kang Zhensheng 

TITLE=Identification of a Novel Alternaria alternata Strain Able to Hyperparasitize Puccinia striiformis f. sp. tritici, the Causal Agent of Wheat Stripe Rust

JOURNAL=Frontiers in Microbiology

VOLUME=8

YEAR=2017

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2017.00071

DOI=10.3389/fmicb.2017.00071

ISSN=1664-302X

ABSTRACT=<p>The obligate bitrophic fungus <italic>Puccinia striiformis</italic> f. sp. <italic>tritici</italic> (<italic>Pst</italic>) causes stripe (yellow) rust on wheat worldwide. Here, we report a novel fungal strain able to hyperparasitize <italic>Pst</italic>. The strain was isolated from gray-colored rust pustules, and was identified as <italic>Alternaria alternata</italic> (Fr.: Fr.) keissler based on a combination of morphological characteristics and multi-locus (ITS, GAPDH, and RPB2) phylogeny. Upon artificial inoculation, the hyperparasite reduced the production and viability of urediniospores, and produced a typical gray-colored rust pustule symptom. Scanning electron microscopy demonstrated that the strain could efficiently penetrate and colonize <italic>Pst</italic> urediniospores. This study first demonstrates that <italic>A. alternata</italic> could parasitize <italic>Pst</italic> and indicates its potential application in the biological control of wheat stripe rust disease.</p>