Anthracnose is a fungal disease caused by Colletotrichum species that is detrimental to numerous plant species. Anthracnose control with fungicides has both human health and environmental safety implications. Despite increasing public concerns, fungicide use will continue in the absence of viable alternatives. There have been relatively less efforts to search antagonistic bacteria from mudflats harboring microbial diversity. A total of 420 bacterial strains were isolated from mudflats near the western sea of South Korea. Five bacterial strains, LB01, LB14, HM03, HM17, and LB15, were characterized as having antifungal properties in the presence of C. acutatum and C. gloeosporioides. The three Bacillus atrophaeus strains, LB14, HM03, and HM17, produced large quantities of chitinase and protease enzymes, whereas the B. amyloliquefaciens strain LB01 produced protease and cellulase enzymes. Two important antagonistic traits, siderophore production and solubilization of insoluble phosphate, were observed in the three B. atrophaeus strains. Analyses of disease suppression revealed that LB14 was most effective for suppressing the incidence of anthracnose symptoms on pepper fruits. LB14 produced antagonistic compounds and suppressed conidial germination of C. acutatum and C. gloeosporioides. The results from the present study will provide a basis for developing a reliable alternative to fungicides for anthracnose control.

A bioinspired M-13 bacteriophage-based photonic nose was developed for differential cell recognition.

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Conidiation and appressorium differentiation are key processes for polycyclic dissemination and infection in many pathogens. Our previous study using DNA microarray led to the discovery of the MoYAK1 gene in Magnaporthe oryzae that is orthologous to YAK1 in Saccharomyces cerevisiae. Although the mechanistic roles of YAK1 in S. cerevisiae have been described, roles of MoYAK1 in M. oryzae, a phytopathogenic fungus responsible for rice blast, remain uncharacterized. Targeted disruption of MoYAK1 results in pleiotropic defects in M. oryzae development and pathogenicity. The ΔMoyak1 mutant exhibits a severe reduction in aerial hyphal formation and conidiation. Conidia in the ΔMoyak1 are delayed in germination and demonstrate decreased glycogen content in a conidial age-dependent manner. The expression of hydrophobin-coding genes is dramatically changed in the ΔMoyak1 mutant, leading to a loss of surface hydrophobicity. Unlike the complete inability of the ΔMoyak1 mutant to develop appressoria on an inductive surface, the mutant forms appressoria of abnormal morphology in response to exogenous cyclic adenosine-5'-monophosphate and host-driven signals, which are all defective in penetrating host tissues due to abnormalities in glycogen and lipid metabolism, turgor generation and cell wall integrity. These data indicate that MoYAK1 is a protein kinase important for the development and pathogenicity of M. oryzae.