Compositional Changes in Compost during Composting and Growth of Agaricus bisporus.

Samples from conventional compost taken at various stages of composting and mushroom (Agaricus bisporus) growth were analyzed for changes in 80% ethanol and water extracts, monosaccharides in acid hydrolysates of polysaccharides, lignin concentration, and lignin structural features. Variable amounts of extraneous inorganic solids in the form of fine sandy particles were removed by sedimentation of the samples in a carbon tetrachloride-dibromomethane mixture. During composting, about two-thirds of the initial wall polysaccharides were consumed by compost microorganisms, and only 17% of the total polysaccharides were used during mushroom production. The relative lignin content of composts as measured by the acetyl bromide procedure increased, both during composting and mushroom growth, and the chemical structure of lignin was altered by condensation and oxidation reactions.

Leucogyrophana pinastri, a wood decay fungus as a probable cause of an extrinsic allergic alveolitis syndrome.

Two patients were suspected of having extrinsic allergic alveolitis due to exposure to an agent in their home environment. On inspection of their houses, fungal decay was evident in the floorboards, and fungal spores were found deposited on many surfaces. The decay fungus was later identified as Leucogyrophana pinastri. Using an extract of the fruiting bodies and mycelium of this fungus, precipitating antibodies were identified in the sera of both patients. Based on the known exposure by the two patients to these small spores, the absence of a likely alternative allergen, the similarity between these two cases, and the positive precipitin test results, L. pinastri was considered to be the most likely cause of extrinsic allergic alveolitis in our cases.

Insect grazing on Eucalyptus in response to variation in leaf tannins and nitrogen.

Many species of Eucalyptus, one of the dominant genera in Australian forests and woodlands, contain high levels of tannins and other phenols and are also heavily damaged by grazing insects. These phenols do not appear to affect insect attack because a wide range of concentrations of condensed tannins and other phenols in leaves of 13 Eucalyptus sp. influenced neither feeding rates of Paropsis atomaria larvae, nor their nitrogen use efficiencies. We discuss reasons why tannins may not appreciably reduce the availability of nitrogen (N) to these insects. Performance was directly related to leaf N concentration, and growth rates, N gains, and N use efficiencies all increased as leaf N content increased, although absolute feeding rates remained constant. These relationships differ from those found in insects feeding on other plants, and we suggest that the low N contents common in Eucalyptus leaves may be responsble. We propose that the extensive damage observed in many eucalypts is in part related to the high feeding rates maintained by individual larvae.