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A study has been presented in which inoculations were made into the bark of living larch trees in each of the four months January, April, July and October. Every three months, one quarter of the inoculations was harvested and isolations made from all parts of the damaged bark. The wood beneath the inoculations was colonised by T. willkommii within three months in some instances and 41 % of all isolations of its mycelium were from that region. No sequential invasion of lesions comparable with that previously described for natural cankers could be seen and the composition of the fungal flora of natural and artificial lesions was different. Trichoderma viride, the most common fungus after T. willkommii in artificial lesions, had been infrequent in natural cankers.

The fungi decomposing broadleaved litter could be grouped into at least three distinct associations: those colonising leaves on the tree; those colonising newly fallen litter, and those colonising older litter from the soil. An overall estimate of the importance of a given species could be obtained by combining data on abundance, duration of activity, and decomposing ability of sterile litter. The flora of higher fungi in high-altitude oak woodlands was shown to have significant differences from that at low altitudes. [ABSTRACT FROM AUTHOR]

In a study of 56 patients undergoing prostatectomy, it has been shown that when bacteriuria developed in the presence of an indwelling catheter, the infecting organism could almost always be found colonising the urethra from 1 to 3 days before it entered the bladder. [ABSTRACT FROM AUTHOR]

Production of mycotoxins in cereal grains has been reported only occasionally, although potentially toxigenic fungi are often present in stored grain. The effect of environmental conditions on the growth of fungi colonising grain is described. Reported natural occurrences of toxins in grain suggest that the Fusarium toxins, zearalenone and T-2, and ochratoxin and citrinin from Penicillium viridicatum may be the most common although aflatoxins may occur in maize. There have been few reports of these toxins in Britain. A multidisciplinary approach is necessary to ensure new methods of storage do not increase the risk of mycotoxin formation. [ABSTRACT FROM AUTHOR]

Four cases of invasion of the glabrous skin by filamentous, non-dermatophyte fungi are described. Aspergillus niger was found in the toe-webs of 1 patient and Allescheria boy dii in those of another. Fusarium solani and F. oxysporum var. redolens were colonising necrotic skin in 2 diabetic patients. It was concluded that in all these cases the fungal invasion was purely saprophytic in nature. The difficulty of discriminating between contamination and saprophytic invasion of the skin by non-dermatophytes is discussed and criteria for making the distinction are suggested. [ABSTRACT FROM AUTHOR]

In this paper the author has described eight more interesting foliicolous ectoparasites from Jabalpur (M.P.) India. Out of these Pyrenochaeta mitteriellae Sahni an hyperparasite on Mitteriella zizyphina Syd. colonising leaves of Zizyphus xylopyra Willd., Chaetothyrium jasminicola Sahni on Jasminum sambac Ait., and Myiocopron parviflorae Sahni on Ixora parviflora Vahl are reported as new species. Micropeltis ekmanii Petr. & Cif. on leaves of Carissa spinarum L., Asterinella ixorae Ryan on leaves of Ixora parviflora Vahl and Plenotrichum sp. on leaves of Casearia tomentosa Roxb. are three new fungus records for this country. The remaining two fungi viz. Asterina tonduzi ( Speg.) Syd. on Flacourtia ramontchi L'Herr. and Balladynopsis negrii ( Cast.) M. B. Ellis on Randia dumetorum Lamk. are new state reocrds. [ABSTRACT FROM AUTHOR]

SYNOPSIS. The class Rotifera includes species which reproduce solely by apomictic female parthenogenesis and species which alternate this “asexual” reproduction with ordinary sexual reproduction. The transition between asexual and sexual reproduction is controlled by the environment. Laboratory studies with the genus Asplanchna have shown that it is possible to identify specific molecules as inducers, which act on embryos in utero to modify their development and determine whether they will mature as sexually or asexually reproducing females. Moreover, an evolutionary rationale can be provided for the response to these particular environmental controlling agents, which are such that sexual reproduction will occur only when it will result in successful fertilization. Rotifers are opportunistic or colonising organisms, which implies selection for rapid reproduction. We suggest that this may account, at least in part, for the origin of both apomicitc parthenogenesis and certain features of the pattern of macromolecular syntheses during development. To account for the success of those rotifers which have lost sexual reproduction entirely, we note that accumulation of mutations during periods of exponential apomictic parthenogenetic reproduction, together with “mitotic” crossing-over, could theoretically produce sufficient genotypic diversity to provide evolutionary flexibility. This would eliminate a major advantage of sexual reproduction. [ABSTRACT FROM PUBLISHER]

Grazing of a hill in southern Sweden influenced the vegetation pattern and local habitat. The microclimate and soil water within grazed vegetation (Hypnum and Festuca sites) and ungrazed tussocks of Ononis repens (Ononis sites) on the southern slope were compared and were related to measurements from corresponding positions on the northern slope (Plearozium sites) and an ungrazed beechwood area (wood site) on the southern slope. Some investigations were also performed on a bare surface on the southern slope. Microclimatic and soil moisture conditions within the Ononis site and the Hypnum and Festuca sites were different. Habitat conditions at the Ononis site were more similar to the wood site than the Hypnum and Festuca sites. Vegetation also differed and species, otherwise restricted to the northern slope, were found within the Ononi, tussocks, where some species showed greater vitality. Extreme conditions of microclimate, especially on the bare surface of the southern slope, may influence competition between colonising species. [ABSTRACT FROM AUTHOR]

The article discusses the need to recognize the classification of aquatic plant communities to address issues on aquatic vegetation in Great Britain. Accordingly, the three major methods of classifying plant communities includes warming, types of British Vegetation, and accordance to the Norfolk Broads which is contributed by Miss Marietta Pallis. For warming, plant communities are being classified according to growth form. For British Vegetation, plant communities are laid on the importance of the habitat factor. Lastly for Norfolk Broads concerns primarily on how the relation between successive plant communities is described regarding aquatic and fen communities as part of one succession being applied to British vegetation.