Abstract
Seed of Scots pine was examined for fungi from pollination to two years of storage. Sclerophoma pithyophila, in the past associated with needle drop, constituted practically the entire flora of seed in unripe cones on the trees, in some cases being isolated from up to 98% of the seeds. The flora of the seeds changed markedly during cone drying and seed extraction, with common field fungi, sometimes also isolated from the cone scales, appearing in fairly low numbers. During storage there was a steady increase in the frequency of isolation of typical storage fungi, such as Penicillium spp. Because of the low temperature and relative humidity of storage Aspergilli were rarely isolated. The flora of different batches of stored seed was fairly similar, despite occasional marked differences before extraction. There was evidence that the initial inoculum of the storage flora came from the extraction unit and the population was subsequently governed by the conditions of storage. Due to the absence of surface growth on seeds it is suggested that increases in the frequency of isolation of species during storage was due to sporulation on exposed surfaces within damaged seeds. A series of experiments were conducted to determine the effect of environmental factors on the mycoflora. Two separate studies were made and are included as appendices. Firstly, there was a numerical taxonomic study of 'black yeasts', including and secondly an examination of the pathogenicity and identity of a species of Phomopsis isolated from diseased cones and seedlings.