Abstract: The Nikkomicin is an antibiotic exuded from Streptomyce Tendea TVE. The experimental results of spores germination have shown that the available Nikkomicin concentration of 0.1-0.2ppm is effective to purple blotch of onion ( Alternaria porri giferri ), inducing deformity of spores bud and mycelium of pathogen. The concentration of O.Sppm will cause distortion of mycelium of alternaria leaf spot of Chinese cabbege ( Alternaria brassicae sacc ) . It was proved that the antibiotics possess strong activity of inhibition to abovementioned pathogens.

Key words: Nikkomycin, Cabbage Leaf Spot, Onion Purple Blotch, Germicide