A preliminary study of the growth of fungi and bacteria from temperate and antarctic soils in relation to temperature

Abstract

The growth of fungi isolated from a lowland temperate site (Roudsea Wood National Nature Reserve), an upland temperate moorland (Moor House National Nature Reserve) and an oceanic Antarctic island (Signy, S. Orkneys) was compared at 1, 14 and 25°C. This showed that low temperatures caused greatest retardation of growth in fungi from the warmest site (Roudsea) and least from the coldest site (Signy Island). At Moor House, fungi which were isolated most frequently in winter were able to grow better at 1°C than summer forms. The fungal flora of Signy Island was restricted and consists of cold tolerant cosmopolitan species which have been selected by or become adapted to the prevailing low temperatures. Of fungi isolated from any two of the sites, Mortierella alpina and Mucor hiemalis showed temperature adaptation correlated with prevailing site temperature, while Trichoderma viride, Penicillium thomii, and P. frequentans showed no adaptation. The growth of bacteria isolated from Moor House and Signy Island was also compared at 1,13 and 25°C, and 56 per cent of the Moor House isolates grew best at 25°C compared with 2 per cent of the bacteria from Signy Island. The majority of the latter grew best at 13°C and were Gram-negative rods.