Screening and Identification of the Novel Bacterial Strain Alcaligenes faecalis B137W and its Inhibitory Effects against the Plant Pathogenic Fungus, Rhizoctonia solani.

The bacterial strain Alcaligenes faecalis B137W, which has antagonism against Rhizoctonia solani, was firstly screened out from an integrated rice-duck ecosystem field by the dual culture method. Morphological, physiological and biochemical characteristics as well as the sequence of the 16S rDNA gene and phylogenetic analysis showed that the strain B137W, whose 16S rDNA sequence has been registered in Gene Bank (accession number KC199967). It belongs to Alcaligenes faecalis, and has high homology with the model strain Alcaligenes faecalis ATCC8750. This strain obtained one national patent from China: ZL201310305517.7. The fermented filtrate of B137W was used to test its inhibitory effect on fungal plant pathogens. The results showed that it has an inhibitory rate of 60.26% against Rhizoctonia solani within 48 h, without significant differences in the rate of validamycin. It also showed a broad range of inhibitory effects on Pyricularia grisea, Fusarium graminearum, Ustilaginoidea virens and Sclerotinia sclerotiorum. [ABSTRACT FROM AUTHOR]