论文部分内容阅读
兴安落叶松[Larix gmslini]是我国东北林区分布广泛的重要用材树种。自1976年发现了癌肿病。病原菌是韦氏毛杯菌[Trichoscpphella willommii(Hart.)Nannf.]。病害发生在人工林、天然更新幼林和过熟的天然母树上的枝与干上,显然幼令林的发病率最高。发病率最低为21％,最高为97％,一般为50％。枝病后发生棱形癌肿,干病后发生各种形状的癌肿和流脂病状,癌肿表面有同心环状的突起溃疡伤。一旦发病年年发展,极难恢复。在溃疡伤的边缘产生盘状子实体,外白内橙黄。天然林中的病树,是人工林大面积发病的侵染来源。霜冻与温差大所造成的日灼伤,是发病的重要诱因,被冻死的芽和小枝以及皮部,是病菌的最有可能的主要侵染途径。建议防治措施应包括:普查病情、域内检疫,提高林分卫生标准、造混交林、不在低洼地和落叶松迹地上造林、适当加大初植密度以防冻害、成林后适时间伐、精心修枝,以减少侵染来源和病菌的侵染机会。
Larix gmslini is one of the most widely used timber species in northeastern China. Cancer disease has been discovered since 1976. The pathogen is Trichoscaphella willommii (Hart.) Nannf.]. Disease occurs in plantations, natural regeneration of young and over-mature natural tree branches and stems, apparently the highest incidence of young trees. The lowest incidence of 21%, up to 97%, usually 50%. Branches after the occurrence of prismatic cancer, dry disease occurs after a variety of forms of cancer and fluid lipidosis, cancer surface concentric rings protruding ulcer injury. Once the onset of disease development, extremely difficult to recover. In the edge of the ulcer injury disc shaped fruiting body, the outer white yellow. The diseased tree in natural forest is the source of infection in a large area of plantation. Frost and temperature caused by large burns, is the incidence of an important incentive to be frozen to death buds and twigs and skin, is the most likely pathogen infection. Proposed prevention and treatment measures should include: the census of the disease, the region quarantine, improve the health standards of the stands, mixed forest, not lowland and larch loose afforestation, appropriate initial planting density to prevent frost damage, appropriate time after cutting, careful repair Branches to reduce the chances of infection and pathogen infection.