Fig. 3

Isolation of antifungal Pseudomonas alcaligenes ZK-2 from turfgrass seeds by mono-enrichment of the pathogenic fungus Clarireedia paspali. a Antifungal test of ZK-2 against four selected fungal pathogens. 1#, ZK-2; 2#, E. coli Top10; 3# and 4#, positive controls (3#, Bacillus subtilis NCD-2; 4#, Lysobacter enzymogenes OH11) exhibit known antifungal activity but no antibacterial activity. A, B, C and D, PDA plates pre-inoculated with Clarireedia paspali, Magnaporthe oryzae, Botrytis cinerea and Fusarium verticillioides, respectively. b Antibacterial activity of ZK-2 against four selected pathogenic or non-pathogenic bacteria. E, F, G and H, LB plates pre-inoculated with Psa C48, Pseudomonas syringae pv. tomato DC3000, Acidovorax citrulli xjl12 and Xanthomonas campestris 8004, respectively. c Maximum-likelihood phylogenetic tree constructed based on housekeeping genes 16S rDNA, gyrB, rpoD and rpoB, showing the relationship between strain ZK-2 and closely related strains. Cellvibrio japonicas DSM 16015 T was used as the outgroup. The sequences of 16S rDNA (1406 bp), gyrB (1040 bp), rpoB (1142 bp) and rpoD (585 bp) genes were retrieved from GenBank deposits or whole genome sequences. GenBank accession numbers are given in parentheses in the following order: 16S rDNA, gyrB, rpoB and rpoD genes). Numbers at nodes are bootstrap values from 1000 repetitions (≥ 50%). Strain ZK-2 is highlighted in bold. Bar, 0.01 substitutions per nucleotide position