单孢融合性实验法鉴定采自四川北部的小孔异担子菌(英文)

Heterobasidion parviporum Identified from Northern Sichuan Province with the Aid of Mating Tests

在四川北部九寨沟和黄龙保护区的云杉、松树和铁杉上发现异担子菌 ,并从 6号标本中分离到 73个单孢菌株。在每个标本中随机选取 2个菌株分别与欧洲的原始多年异担子菌、小孔异担子菌和冷杉异担子菌的单孢菌株进行融合性交配。试验表明 ,这 6号标本都是小孔异担子菌。四川的菌株与欧洲的原始多年异担子菌交配不融合 ,而与欧洲的小孔异担子菌完全融合 ,并在交配后的菌落中形成锁状联合 ,且在交配的菌落中不产生拮抗线。虽然四川的菌株与欧洲的冷杉异担子菌有较高的融合性 ,但这些交配大部分为单项交配 ,即只在四川一侧的菌落中产生锁状联合 ,而且在交配的菌落中多数产生拮抗线。研究样品全部采自天然林 ,小孔异担子菌在四川经营林分中的致病性还有待进一步调查。

Specimens of Heterobasidion annosum s.l. were collected on fallen trunks or stumps of Picea, Pinus and Tsuga from natural reserve of Jiuzhaigou and Huanglong of northern Sichuan province. Seventy three homokaryotic single spore cultures were isolated from six samples. Two homokaryons of each collection were identified in a mating test with one or two homokaryotic tester strains of European H. annosum, H. parviporum , and H. abietinum. Mating tests showed that all these collections belong to Heterobasidion parviporum (the S group of Heterobasidion annosum s.l. ). The Sichuan isolates did not form clamp connections in the pairings with H. annosum s.str ., and a strong demarcation line developed in all these pairings. In contrast, the Sichuan isolates mated almost perfectly with European H. parviporum , the clamp connections developed in both sides of the pairings, and no distinct demarcation line was present in most of these pairings. The Sichuan homokaryons were also compatible with European H. abietinum , but in most of these pairings clamp connections were mostly found in the colonies from Chinese sides, but not in the European tester sides, and a demarcation line was present in most of the pairings. All studied materials were from natural forests of northern Sichuan, and the pathogenicity of H. parviporum in the managed forests of the province is unclear.