Department of Biosciences, Mangalore University, Mangalagangotri, Mangalore, Karnataka, India.
Microb Ecol. 2011 Apr;61(3):635-45. doi: 10.1007/s00248-011-9803-1. Epub 2011 Jan 27.
We mapped filamentous fungal association with mechanically "hard" and "soft" woody litter naturally deposited in a stream of the Western Ghats of India. Using a durometer (rubber hardness tester), the toughness of surface of wood collected from stream was determined by considering durometer reading from 60-72 to 30-37 as hardwood and softwood, respectively. From each wood (1.5 cm diameter), two segments each of 3 cm length were excised and vertically cut into nine sections comprising eight marginal and one central section. From three stream locations, hardwood and softwood sections were assessed for the occurrence of lignicolous and Ingoldian fungi. A first set of wood sections was incubated in damp chambers up to 4 months with periodical screening (every 2 weeks) for lignicolous fungi. Another set was incubated in bubble chambers up to 72 h to ascertain colonization of Ingoldian fungi. In hardwood sections, 17 lignicolous fungi (ascomycetes, four; mitosporic fungi, 13; mean, 6.8; range, 6-8/section) and ten Ingoldian fungi (mean, 2; range, 0-4/section) comprising nine lignicolous (11.1-40.7%) and three Ingoldian (11.1-14.8%) fungi as core-group taxa were recovered. In softwood, ten lignicolous fungi (ascomycetes, 0; mitosporic fungi, ten; mean, 3.8; range, 2-5/section) and 26 Ingoldian fungi (mean, 8.1; range, 5-10/section) comprising six lignicolous (11.1-85.2%) and 12 Ingoldian (11.1-88.9%) fungi as core-group taxa were recovered. The ratio of lignicolous fungi/Ingoldian fungi was higher in hardwood than softwood (1.7 vs. 0.4). The spore output of Ingoldian fungi was higher in softwood (mean, 901 g(-1); range, 80-2546 g(-1)) than hardwood (mean, 21 g(-1); range, 0-140 g(-1)). The Shannon diversity of lignicolous fungi was higher in hardwood than softwood (3.604 vs. 2.665), whereas it was opposite for Ingoldian fungi (3.116 vs. 3.918). The overall fungal diversity was higher in softwood than hardwood (4.413 vs. 4.219). The range of Jaccard's index of similarity among wood sections was higher in lignicolous fungi (8-71% and 13-75%) than Ingoldian fungi (0-50% and 8-55%) in hardwood and softwood. The rarefaction indices of expected number of taxa against hardwood sections revealed higher and persistent lignicolous fungi than the Ingoldian fungi, while the Ingoldian fungi were persistent in softwood sections, although they were lower than lignicolous fungi. Our study demonstrated the dominance of lignicolous fungi and Ingoldian fungi in hardwood and softwood, respectively.
我们对在印度西高止山脉溪流中自然沉积的“硬木”和“软木”木质废料中的丝状真菌进行了关联研究。使用硬度计(橡胶硬度测试仪),通过考虑硬度计读数从 60-72 到 30-37 来确定从溪流收集的木材表面的韧性,分别将其视为硬木和软木。从每块木材(直径 1.5 厘米)上,各切取两个 3 厘米长的段,然后将其垂直切成 8 个边缘段和 1 个中心段。在三个溪流位置,评估了硬木和软木段中木质和 Ingold 真菌的发生情况。第一组木材段在潮湿室中培养长达 4 个月,并定期(每 2 周)进行筛选,以检查木质真菌。另一组在气泡室中培养长达 72 小时,以确定 Ingold 真菌的定植情况。在硬木段中,发现了 17 种木质真菌(子囊菌纲,4 种;有丝分裂真菌,13 种;平均,6.8;范围,6-8/段)和 10 种 Ingold 真菌(平均,2;范围,0-4/段),包括 9 种木质(11.1-40.7%)和 3 种 Ingold 真菌(11.1-14.8%)作为核心群分类单元。在软木中,发现了 10 种木质真菌(子囊菌纲,0;有丝分裂真菌,10 种;平均,3.8;范围,2-5/段)和 26 种 Ingold 真菌(平均,8.1;范围,5-10/段),包括 6 种木质(11.1-85.2%)和 12 种 Ingold 真菌(11.1-88.9%)作为核心群分类单元。木质真菌/Ingold 真菌的比值在硬木中高于软木(1.7 比 0.4)。软木中 Ingold 真菌的孢子产量较高(平均 901 g(-1);范围,80-2546 g(-1)),而硬木中较低(平均 21 g(-1);范围,0-140 g(-1))。硬木中木质真菌的 Shannon 多样性高于软木(3.604 比 2.665),而 Ingold 真菌则相反(3.116 比 3.918)。软木中的总真菌多样性高于硬木(4.413 比 4.219)。硬木和软木中,木质真菌的 Jaccard 相似性指数范围较高(8-71%和 13-75%),而 Ingold 真菌的范围较低(0-50%和 8-55%)。在硬木段中,预期分类单元数量的稀有指数显示出木质真菌比 Ingold 真菌更为丰富和持久,而 Ingold 真菌在软木段中更为持久,尽管它们比木质真菌少。我们的研究表明,木质真菌和 Ingold 真菌分别在硬木和软木中占主导地位。