在纯培养条件下温度对外生菌根真菌生长的影响

INFLUENCE OF TEMPERATURE ON COLONY GROWTH OF ECTOMYCORRHIZAL FUNGI IN PURE CULTURE

在MMN培养基上,用5—40℃范围内的15种不同温度,对云南省不同针叶林下38种常见外生菌根真菌的44个菌菌株进行纯培养试验。绝大部分菌株的最适生长温度为25℃,最低临界生长温度为7℃,最高临界生长温度为35℃。各种真菌在最适生长温度下的生长速度可分为快、中、慢三种类型。不同菌种的温度生长曲线形状也有多样:一般有尖峰形、宽顶形和缓平形三种。文中还附有各菌株的生长速度、最适生长温度和临界生长温度表。

44 isolates of ectomycorrhizal fungi comprising 38 species were cultured on MMN medium at 15 temperature gradients from 5℃ to 40℃ for 2 weeks. For growth of most isolates, the optimum temperatures ranged from 22 to 27℃ with the optima of 25℃. Most isolates stopped growing at 10℃ and 35℃. A few isolates had a poor growth at 5℃ and 40℃, but at the highest growth temperature for a long time, the isolates were much weakened, even lost their vitality at all. Most isolates of genera Boletus, Leccinum, Suillus, Xerocomus and Pisolithus were fungi of slow growing type, while those of genera Laccaria, Lactarius, Cantharellus, Lycoperdon, Gomphydius, Russula and Oudemansiella were fungi of fast growing type, and fungi of genera Amanita, Boletinus, Cortinarius, Rhizopogon, Scleroderma and Tricholomopsis grew intermediately. But [there were always many exceptions. Different isolates within a species collected from different forest sites maybe react to the temperature variation diversely. For instance, the isolates of Amanita pantherina collected from the spruce forest at altitude above 3400m grew slower than that collected from the pine forest of altitude about 2000m, but it grew faster than the later at low temperature of 10℃for it has long been adapted to the cold alpine circumstance. They were apparently fungi of different ecotypes. From the point of view of selection of ectornycorrhizal fungi, the isolates are required to possess the fast growing ability, to have a more wide range of optimum growth temperature and to be resistant to extreme temperatures.