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991.
Propagules of Trichoderma generally formed less than 3 per cent of the total fungal propagules in a variety of forest soils in the southeastern U.S. and Washington State. The largest populations were found in the F and H organic horizons of the forest floor or under conditions of excessive moisture. T. viride Pers. ex S.F. Gray and T. polysporum (Link ex Pers.) Rifai were largely restricted to cool temperate regions; whereas, T. harzianum Rifai was characteristic of warm climates. T. koningii Oud. and T. hamatum (Bon.) Bain, were the most widely distributed species aggregates and were found in all the climatic regions investigated. Under conditions of excessive moisture, strains of T. hamatum and T. pseudokoningii Rifai were the dominant forms. 相似文献
992.
Abstract. Starry flounder Platichthys stellatus (Pallas) from the Duwamish River estuary, which has received large volumes of pollutants in the past, and starry flounder from two relatively unpolluted reference areas were examined for pathological conditions. Gross and microscopic examination of starry flounders from the Duwamish River estuary revealed one or more of the following unusual liver characteristics in 92% (monthly range 85–100%) of the fish: liver discolouration, liver enlargement, severe fatty vacuolation of the hepatocytes, centrolobular cellular degeneration and necrosis of hepatocytes, megalocytic hepatocytes, proliferating perivascular fibroblasts displacing adjacent liver parenchyma, hepatic structural disarray and increased basophilia of hepatocytes in localized areas. Livers of starry flounders, usually spent spawners, from one of the reference areas also had one or more of these characteristics, although at a much lower frequency (<13%), and these included liver discolouration, increased fatty vacuolation of the hepatocytes and hepatic structural disarray. 相似文献
993.
994.
Michael B. New 《Aquaculture (Amsterdam, Netherlands)》1980,21(2):101-128
This paper contains a bibliography of papers published on dietary and nutritional work with shrimps and prawns. In addition, selected papers on related topics, such as the nutrition of other crustacea, the natural food of shrimps and prawns, and physiology, are included. The bibliography is intended to be an aid to existing workers in the field of shrimp and prawn nutrition, to be a launch pad for scientists entering this field for the first time, and to assist those wishing to review specific aspects of this subject. 相似文献
995.
A turf-banked lobe with a ground soil of post-Pinedale age overlies a buried paleosol which, although thin, appears to have been developed in situ. Organic matter from the Ab horizon of the paleosol yields a radiocarbon age of BP (Gak-3823) which corresponds with the waning stages of the Pinedale Glaciation in the Rocky Mountains. Abundant kaolinite and high amounts of silt and clay suggest that it may have developed over a long time interval. 相似文献
996.
997.
H B Conacher J R Iyengar W F Miles H G Botting 《Journal of the Association of Official Analytical Chemists》1979,62(3):604-609
A method is given for determining monosodium glutamate (MSG) in soups and soup bases by gas-liquid chromatography (GLC) of the trimethylsilyl ether derivative of glutamic acid. This method compared favorably with existing methods including GLC of the trifluoroacetate (TFA)/butyl ester derivative, and analysis on an amino acid analyzer. In addition, some samples were analyzed by GLC/mass spectrometry. The MSG content of various products ranged from approximately 0.2% in some condensed soups to 13.1% on bouillon cubes. The method, which can detect as little as 0.05%, requires only a 10 min single step derivatization at room temperature and is preferred to the TFA/butyl ester technique. 相似文献
998.
B.J. Macauley 《Soil biology & biochemistry》1979,11(2):175-179
Fungal succession on untreated and fungicide- and insecticide-treated leaves of Eucalyptus pauciflora was compared. Natural succession on untreated leaves fits the general scheme for succession on deciduous tree leaves. Initial colonizers are species of Coelomycetes and Moniliales. When the numbers of Coelomycetes decrease in the late stages of decomposition, the frequency of Penicillium species and species of Zygomycetes increases. The succession is affected only marginally by DDT and dieldrin treatment while benomyl severely restricts the occurrence of most fungal species. The effect of benomyl persists even after exposure for 48 weeks in the field. 相似文献
999.
B.E. Söderström 《Soil biology & biochemistry》1979,11(2):147-148
A technique for assessing the metabolically-active fungal biomass by means of fluorescein diacetate (FDA) staining was recently described (Söderström, 1977). In this note some practical details in the application of this technique to studies of FDA-active fungal biomass in the soil are discussed. 相似文献
1000.
C.B. Cowey J.W. Adron R. Hardy J.G.M. Smith M.J. Walton 《Aquaculture (Amsterdam, Netherlands)》1979,16(3):199-209
Three groups of rainbow trout were given diets containing different amounts (12–36%) of collagenous by-product derived from partially rendered hide fleshings still containing an appreciable amount of saturated fat. A fourth group of trout were given a control diet containing as protein source a fish protein concentrate, and, as a source of essential fatty acids, a marine oil. The diets were fed for 12 weeks, hide fleshings replacing part of the marine oil and fish protein concentrate in the three test diets. Weight gains and protein utilization of the four groups of rainbow trout were all similar with all four diet treatments. No adverse effects on the fish were observed from the use of hard fat, although an increase in the concentration of some monounsaturated fatty acids occurred in tissues of those fish given hide fleshings. Tests of mitochondrial function gave normal values for both control and test fish. Organoleptic tests demonstrated that trout given diets containing hide fleshings were not distinguishable from normal trout. The results show that provided nutritional requirements are met (especially in the present instance with respect to essential amino acids and essential fatty acids) this by-product can form a useful component in trout rations. 相似文献