Study On Prevention And Cure Of Ganoderma Lucidum Of Larix And Pinus Koraiensis

Forest root-rot of Pimis koraiensis and Larix gmelinii is a kind of severely infective disease, which becomes more serious in seedyard. In Shi Men Zi Seedyard of Dun Hua Forestry Bureau, Ji Lin Province, China, the disease had led 2,370 trees die, resulting in huge economic loss of seedyard.Since 1998, systemic research has been done for 5 years. We adopted many forestry techniques, including scarifying, weeding, draining, fertilizing, digging far-between dyke, choosing and breeding eximious clone. We also took measures of excavating aperture and irragating root, directly watering root, daubing remedy, stubbing died trees and sterilizing soil in the aperture.We carried through integrated preventional measures of chemical prevention and biological prevention, by using 200×CuSO4, 70% mancozeb 800×5% Chlorothalonil 800×, and Suillus grevillei. All of the meaures got favorable results. The preventional effect exceeded 72%. The incidence of disease descended from 15.5% in 1998 to 2.8% in 2002.This kind of disease was controlled on the whole.We did a lot of experiments, such as separating, cultivating and appraising pathogetic epiphyte, studying physiological character of pathogen, doing manual inoculation, filtrating indoor medicament, and cultivating confrontation in petri dish. The result of study showed the pathogen was Armillaria ostoyae.. Cuture isolations didn't easity get form tissue and fruitbody seperation,but rhi/omycelium was the better separating material. Pathogen grew well on substrate of synthesized potato juice. Three days later, Colony became white and turned into black-brown. Five to six days later, it grew out rhizomycelium.Three isolations of A5.92, A5.146 and A2001, grew best in temperature of 25℃, PH of 6.0-6.4. The best carbon sourse were dextrose and maltose. The best nitrogen sourse were carbamide and zymoid powder. They couldn't grow well on inorganic nitrogen sourse of KNOa and (NH4)2HPO4.The test result of manual inoculation showed the three isolations could cause disease easily. A5.146 and A2001 could more easily cause disease. The delitescence of the disease is about two years. Two and a half years later, the trees would die. The main way of germina incursion was the cut.Test result of indoor confrontation showed six mycorrhizal Fungi, such as Suillusgrevillei, and two Fixing Engineering restrained pathogen A5.92. S. greville, Cortinarius russus and Laccaria laccata had the strongest restraint. They not only produced the most distinct inhibition zone and restrained the growth of pathogen, but also bestrowed pathogen and grew on it. It could be used for biological protetion and cure.