Efficiency of some bioagents for treatment of tomato plants infected with botrytis cinerea

Botrytis cinerea is quite destructive and damaging plant disease, which infect tomato and many other plants. Effective means of protection using bioicides is of interest in recent years. The used bioagents were Streptomyces anulatus SM21, S. coelicolor SM1, Bacillus pumilus and Trichoderma harzianum. They were selected for the high production of lytic enzymes including chitinase and protease on solid and broth media. Effect of these bioicides on spore germination and radial growth of Botrytis cinerea in vitro were recorded. Streptomyces anulatus SM21 was the most active bioagent and inhibited Botrytis cinerea spore germination by 83% and inhibited fungal growth (inhibition zone diameter, 26.5 mm). Tomato plants were grown in sterile soil and infected with Botrytis cinerea. The infected plants recoded significantly higher level of pectinase, peroxidase and catalase enzymes compared to control plants (non infected plants) while treatment with biocides decreased levels of both peroxidase and catalase to levels near to that of healthy plants. Moreover, inoculation of the infected plants with the bioagent decreased the fungal infection and enhanced plant growth criteria. Shoot height (cm /plant) root depth (cm/plant), number of leaves, dry weights of shoot and leaves were enhanced compared to infected plants. Infection of the plants with Botrytis cinerea decreased Chlorophyll a+b content of fresh leaves, Nitrogen (N), Phosphorous (P) and Mg+2 contents (mg/g) of the shoot system compared to healthy plants while increased total soluble protein and total soluble sugars. Treatment of plants by biocides removes almost the bad changes associated with the plant fungal infection. The most effective treatment was using Streptomyces anulatus SM21. In conclusion, Botrytis cinerea can be controlled using Streptomyces anulatus SM21, S. coelicolor SM1, Bacillus pumilus or Trichoderma harzianum due to the presence lytic enzyme and their effects were similar to that obtained by the antifungal Mancozeb.