Wachstumshemmung von Stammfäulepilzen und von Gremmeniella abietina durch Bacillus subtilis

Inhibition of butt rot causing Basidiomycetes and of Gremmeniella abietina by Bacillus subtilis . A zone of inhibition was observed when the fungi were inoculated into the test plates with malt agar either together with B. subtilis (fast growing Basidiomycetes) or two weeks before B. subtilis (slow growing fungi). With some of the fast growing Basidiomycetes a zone of inhibition was observed only during the early growth phase. Sparassis crispa, either not growing or with restricted growth when transferred to the plates together with B. subtilis, completely suppressed the Bacillus culture when inoculated into the plates two weeks before B. subtilis.     

Eine Methode zur Erfassung von Verlauf und Grad der Schädigung von Nadelbaumbeständen

A procedure for the registration of the time course and degree of injury in conifer stands. Missing tree rings are detected by dendrochronological methods and systematically recorded. A procedure is described for the registration of the time course and the extent of injury in conifer stands. A highly significant correlation is demonstrated between the extent of injury in European Silver Fir and the average sulfur content in Norway Spruce needles on the basis of the bioindicator network of the Bayer. Landesamt für Umweltschutz; sulfur content in spruce needles is taken as a measure of sulfur burden of an area.     

Der Einfluß von Fluorverbindungeii auf den Chlorophyll a+b-Gehalt von Pappelblättern im Freiland bei verschiedener Belastung1

The effect of different concentrations of fluorine on the content of chlorophylls a and b in poplar leaves. The concentrations of the chlorophylls a and b and of the fluoride ions in poplar leaves were measured regularly from May to September 1974. The concentration of F increased steadily whereas the concentration of the chlorophylls decreased by 30% compared to first appearance of the leaves. The content of F- to that of chlorophyll a and b cannot be correlated.     

Untersuchungen zur Variabilität von Lophodermium pinastri

Studies of the variability of Lophodermium pinastri. I. Cultural Variants. Lophodermium pinastri is a variable fungus species. From its behaviour in artificial culture 3 constant, morphological main types are observed. These are described in detail. Observations on sectoring found and on reaction types between various fungus isolates are given.     

Untersuchungen zur Variabilität von Lophodermium pinastri

Studies of the variability of Lophodermium pinastri. II. Differences in physiological behaviour . In culture trials with numerous strains of Lophodermium pinastri of different provenances the influence of temperature, pH and vitamins on growth was studied as well as ability to produce starch hydrolyzing enzymes. On the basis of these tests, the strains investigated could be divided into five groups.     

Über den Einfluß fluorhaltiger Fabrikabgase auf den Phenolgehalt von Fichtennadeln

The effect of industrial fluoride air pollutants on the phenolic contents of Norway spruce needles . Potted Norway spruce trees of two clones were exposed under natural conditions at various distances from an industrial fluoride source. The new needles were analysed periodically for their phenolic content. The group of trees closest to the fluoride source contained the highest amount of phenols.     

Der Einfluß von Fluorverbindungen auf die Chloroplasten-pigmente von Pappel-, Holunder- und Fliederblättern im Freiland bei verschiedener Belastung1

The effect of different concentrations of fluorine on the chloroplast pigments of Poplar, Elder and Lilac occurring in the field. An important aim when studying the effects of pollutants is to find methods indicating very early injury. The concentrations of the chlorophylls a and b and of the carotinoids in leaves of Populus canadensis Moe., Sambucus nigra L., and Syringa vulgaris were measured. When affected by fluoride-ions the leaves of P. canadensis show significant loss of the three pigments. The two other species seem to be more resistant.     

Die Leitfähigkeit von Fichtenborken-Extrakten als empfindlicher Indikator für Luftverunreinigungen

The Conductivity of Bark-Extracts from Spruce, a Sensitive Indicator for Air Poilution . Bark of spruce is a useful and sensitive indicator for air pollution. The latter may be determined more precisely by electrolytic conductivity of bark extracts than by pH-value or sulphate level of foliage. By an additional simple sulphate analysis of bark extracts the effects of SO₂ may be distinguished from those of certain components in dust.     

Der Einfluß gasförmiger Luftschadstoffe auf die EpicuticularWachse von Quercus robur

Influence of gaseous pollutants on the epicuticular wax of Quercus robur . The effects of SO₂, NO, and ozone on the epicuticular wax of Q. robur were studied by scanning electron microscopy and by measuring the contact angle of water droplets on the leaf surfaces. The treatments did not induce any significant differences in the wax micromorphology.     

Veränderung der Krankheitsdisposition von Forstpflanzen durch Herbizide

Modification in disease-sensibility of forest plants by herbicide treatment. III. Damping off. A study was made of the effect of the two herbicides, Simazin and TOP-KH (salt of 2,4,5-T) on attack on seedlings of two provenances of Norway spruce by different damping off fungi.In addition, the effect of the two herbicides on the growth of these fungi in arlificial culture was investigated. Different levels of attack on the seedlings were related to the herbicide applied, its concentration and the origin of the spruce. The results gave evidence for a change in susceptibility of the host due to the herbicide.     

Untersuchungen über den Einfluß von Cuticularwachsen auf die Infektionsfähigkeit pathogener Pilze

The effect of cuticular waxes on the infection rate of pathogenic fungi. 2. Rhytisma acerinum, Microsphaera alphitoides and Fusarium oxysporum . Cuticular waxes of Acer and Quercus species stimulate germination rate and germ-tube development of certain foliar pathogens. The stimulation increases with host susceptibility. In the case of Rhytisma acerinum, the chemical composition of the leaf wax may be responsible for the host specificity of physiological races. Cuticular waxes showed a marked effect on Fusarium oxysporum also. In some cases, individual chemical components of different fractions seem to play a role in the mechanism of resistance.     

Züchtung von Reinkulturen des Pilzes Lophodermium pinastri (Schrad.) Chev. zur Entstehung von sexuellen Fruchtkörpern (Hysterothecien)

Production of hysterothecia from pure cultures of Lophodermium pinastri (Schrad.) Chev. A method is described for the production of hysterothecia from pure cultures of L. pinastri. Previously sterilized needles of Finns sylvestris, after being overgrown on the culture dish are removed and put on living moss under natural conditions. In 2–2,5 months hysterothecia appear.     

Untersuchungen über den Einfluß von Cuticularwachsen auf die Infektionsfähigkeit pathogener Pilze

The effect of cuticular waxes on the infection rate of pathogenic fungi. 1. Lophodermium pinastri and Botrytis cinerea . Spore germination and growth rate of germ-hyphae of Lophodermium pinastri and Botrytis cinerea are influenced by low concentrations of cuticular waxes, added to the germination medium. The stimulating effect increases with decreasing resistance of the species or race used for wax sampling. Generally the separately tested alcohol-, aldehyde-, ester-, fatty acid- and hydrocarbon fractions induce similiar but less pronounced reactions than total waxes. Exceptions occur. They led to suggestions in direction to single chemical components causing resistance. – Finally alcohol and hydrocarbon chromatOgrams of cuticular waxes for Pinus montana, P. nigra and Picea abies are presented for the first time.     

Üer das Auftreten von Ozon und Stickstoffoxiden in Waldgebieten Österreichs

Studies on the presence of ozone and nitrogen oxides in Austrian forests. Ozone and nitrogen oxide measurements were made in the region of Innsbruck/Tirol. Low concentrations of ozone and relatively high concentrations of nitrogen oxides were found in Hall (560 m. a. s. 1.). As opposed to this, the concentration of ozone at Patscherkofel (1954 m. a. s. 1.) showed, in winter, a very high base level while nitrogen oxides could not be detected there. The course of the mean daily runs depended on season and the particular gas. The increased base level of ozone at higher altitudes as well as the combination of ozone with other harmful gases in over-crowded areas is considered as an additional stress for forest vegetation. The occurrence of all smog components at the same time and their combination leads to an intensifi-cation of single effects. The phytotoxic effect of the main pollutant SO2 is especially increased by ozone and nitrogen oxides in overcrowded areas.     

Die Wirkung der Dämpfe von Erdölbitumen auf Pflanzen1

The effect of vapours from asphaltic bitumen on plants . Asphaltic bitumen vapours escape from hot-mix asphalt plants and are deposited on leaves and shoots. Experiments were initiated to show whether such droplets cause injuries to plants. Results show that only certain sensitive plants develop symptoms, and then only when more than 3 mg of condensate are deposited per 100 cm² of leaf surface. Injuries caused by bitumen vapours and those caused by coal-tar vapours were closely related. They were both activated by UV-light and the symptoms were similar though milder in the case of bitumen. The differences are mainly due to the widely dissimilar content of aromatic hydrocarbons, the photoactivated agents common to the products.