| On the basis of ecologic balance, developing the complex biological preparation as a goal, we first explored two compatibly antagonists to control the leaf disease of forest plant and hoped this two antagonistic fungi could play a cooperative role in controlling the pine needle blight. The main research results were as follows:1 , The dual test showed the two antagonistic fungi(Gliocladiutm virens ,Bacillus firmus)had some differences to Pestalotia funerea in the inhibition mode. The role of G virens to the P.funerea, mainly displayed the competition in the nutrition and space, but the B. firmus had the distinct inhibition zone to the P. funerea and the hyphae of the target-pathogen became sparse, dry, and yellowing when dual test for 4-5days .2 , The parasitism of G virens to the P.funerea was observed by the scanning electron microscope. The hyphae of Gvirens could grow parallel to or creep above the hyphae of P.funerea. The hyphae of Gvirens could coil the hyphae of the P.funerea, and then growed hyphostroma. The hyphae of P.funerea which was invaded deformed, and some substance oozed from invasion site of P. funerea.3, The distinct effect of the nonvolatilizable metabolites of the two antagonist to the P.funerea was examined. Gvirens had the high inhibitive activity in the primary stage, but B.firmus had long inhibitive activity, better in middle and final stage, this effect offered a theory basis for the cooperative role of the two antagonists in the practice.4 The inhibitory effect of the volatilizable metabolites of two antagonists to P.funerea was analyzed in contrast with the inhibitory rate of the control(CK) . Gvirens , with the highest inhibitory rate of 59.7%, had more excellent and stable inhibitory activity and the effect was more relative with the time, but the inhibitory rate of B.firmus was less relative with the time and the inhibitory effect of B.firmus became stable after 72 hours.5, The inhibitory effect of different component from the filtrate of two antagonists was tested: the polysaccharose, crude fat, and protein produced by Gvirens had inhibitory activity to the spore germination of P.funerea, and the crude fat and protein was more significant, the protein more stable. The crude fat from B.firmus could completely inhibit the Rfunerea's spore germination, the inhibitory effect of polysaccharose and protein also was stable, but polysaccharose more excellent.6, The compatibility of both Gvirens and B.firmus was researched. The fermentation filtrate of Gvirens , under the concentration of 70%, had not distinct inhibitory activity to B.firmus, the biomass of B.firmus would decrease with above the 70% filtrate of Gvirens, but the fermentation filtrate of B.firmus had not inhibitive role to Gvirens.7, The cooperation control of both Gvirens and B.firm to the pine needle blight wasexplored: (1) Pathogen inoculation happened prior to the bio-control treatment for 7 days, however, the disease index and control effect had not distinct differences in any treatments even if combination of the two antagonists, but the susceptibility for different kind of pine were different.(2)when antagonist and pathogen were inoculated at the same time, some control effect to the pine needle blight, including certain extent cooperation control of both Gvirens and B.firm were proved, but it wasn't distinct when two antagonists used separately, and the change of the antagonist concentration had little effect to the control effect.(3)Priority of the antagonist inoculation could distinctly increase control effect, two antagonists combination was better. The disease index of susceptible p'me(Pinus massoniaJ\yunnanensisJ*.tabulaeformis)cou\A decrease to 13-15, the disease index of resistant pine could control to about 3%. B.firmus and Gvirens had not distinctly differences in control effect at the same concentration. At the same antagonist , more concentration, more control effect. (4)The average effect of three bio-control inoculation ways was analyzed. The average... |
PDF Full Text Request