biological control and systemic induction of peroxidase and polyphenoloxidase by trichoderma harzianum in tomato plants infected with nematode meloidogyne javanica

systemic induction of peroxidase and polyphenoloxidase in tomato roots and stem followed by application of split root system method was investigated. root system of tomato seedling in the sixth growth stage were divided in two equal sections after washing and replanted in two adjacent pots and then inoculated with nematode and fungus as fallowing treatments. the second treatment was inoculation of half root by trichoderma spore suspension and half root with sterile distilled water. the first treatment was the inoculation of half of root by nematode and the second treatment was another half of root inoculated just by  sterile distilled water. inoculation of half root by trichoderma and another half by nematode. inoculation of both roots section with sterile distilled water (control). changes of peroxidase and polyphenoloxidase enzymes activities in each root extract and stem section in each treatment were measured daily by spectrophotometer, between zero and seven days. the results showed that trichoderma can increase enzymes activities not only in site of inoculation but also, in other part of plant such as root and stem. maximum of peroxidase activity in root and stem was occurred at 5 and 4 days after inoculation. maximum of polyphenoloxidase activity in root and stem was occurred at 6 and 4 days after inoculation, respectively. the results suggest that trichoderma systemically induce plant defense mechanism and can be considered as a suitable inducer for root- knot nematode management.