Effect of secretion produced by the pine wood nematode and enzymes on pathogenic action in the seedlings of Pinus thunbergii

Pine wood nematode Bursaphelenchus xylophilus (PWN ),monoxenic cultured in Pestalotia sp.was in the buffer of Tris-HCl,0.05 mol/L,pH 7.2,in shanking incubation at 25 ℃ for 72 hours.The supernatant,in which there was secretion of PWN,was filtered through 0.22 μm Millipore and precipitated proteins in 100% of the saturation (NH_4)_2SO_4 solution.The secretion contained cellulase,protease,peroxidase and amylase detected by polacrylamide electrophoresis.Three-year-old seedling of Pinus thunbergii were inoculated with the secretion produced by the pine wood nematode,1%cellulase,1% protease,1% peroxidase and 1% amylase respectively.the result showed that the secretion produced by the pine wood nematode and 1% cellulase could cause necrotic symptoms in the needles of P.thunbergii.It suggests its secretion produced by the pine wood nematode may be a possible candidate of the pothegens.