摘要:

AbstractThis study shows extreme phytotoxicity of 2,3,6‐trichlorobenzoic acid (2,3,6‐TBA) toPinus resinosaseedlings in the cotyledon stage of development. 2,3,6‐TBA caused abnormal seedling development and mort

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1986.tb00206.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractBacteria were always recovered from degraded tissue of large and mid‐sized tarnished plant bug (Lygus lineolaris) lesions, less frequently from small lesions and bumps, and rarely from healthy tissues of current year shoots of hybrid poplar in southern Ontario, Canada. All 209 isolates obtained were gram‐negative rods; 61 were members of the Enterobacteriaceae. Compartmentalized disrupted areas in the xylem were associated with bumps and large insect incited lesions. Large numbers of bacteria were associated with pockets of thick‐walled fibers in the disrupted tissues. Microscopic observations suggest that bacteria contribute to degradation of disrupted tissues through breakdown of the fibers. The role of bacteria in TPB lesion formation, however, is still not

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1986.tb00207.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractEpicuticular wax composition and its variation with needle age was analysed chemically. Needles were taken from conifers at the highest altitude of their local distribution. Quantitative and qualitative differences in the composition of the three conifer waxes were found. Increasing needle age influenced the wax composition inPinus cembraandPicea abies.

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1986.tb00208.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractThe structural degradation of the epistomatal waxes was studied with the scanning electron microscope in needles of five trees ofPicea abies(L.) Karst. differing in their symptoms of decline. The shedding of needles was found to be related to the degree of occlusion of stomates and to occur when about 80 to 90 % of stomates became occluded by a flat and solid wax cover resulting from the structural degradation of the epistomatal wax crystalloids. While this structural degradation stage was not reached before the seventh year in the trees classified as healthy, degradation was dramatically accelerated in the declining trees. The physiological consequences of such structural obstruction could explain many results so far obtained in declining trees.

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1986.tb00209.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractLipids and their fatty acids from the mycelia of aggressive and non‐aggressive strains ofCeratocystis ulmiwere examined at different incubation temperature. The quantity and degree of fatty acid unsaturation were correlated with the pathogenicity of the fungu

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1986.tb00210.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractInfection experiments withAscocalyx abietinaandA. laricina, on cembra pine, mountain pine, and larch between 1979 and 1985 gave very varying results from one year to another. Moderate to very severe disease only occurred after incubation on favourable sites in the subalpine zone. The intensity of disease may depend on local site and microclimatic conditions for infection. Successful infections occurred especially in autumn. An annual infection rate of 10 to 15 percent can endanger an afforestation: in an afforestation in Avers, 50 percent of the trees were killed in some 5 years.

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1986.tb00211.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractTreatments with acidified solutions of pH 3.5 cause alterations in the wax structure of the needles of silver fir and Norway spruce. The wax structures, especially those of the stomata, once they have been damaged, are not capable of complete reorganization even if the needle is repeatedly treated with distilled water.

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1986.tb00212.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

Book reviewed in this article:Deutsche Forschungsgemeinschaft (Hrsg.): Zur Bewertung gesundheitlicher Gefahren für den Anwender von Pflanzenschutzmitteln. Mittg. XIII der Kommission für Pflanzenschutz‐, Pflanzenbehandlungs‐ und VorratsschutzmittelAcid Rain: Economic Assessment. Ed. By P. Mandelbaum.Air Pollution by Photochemical Oxidants. Formation, Transport, Control and Effects on Plants. (R. Guderianedt.)Roane, M. K.; Griffin, G. J.; Elkins, J. R.:Chestnut blight, other Endothia diseases, and the genus Endothia.Peterson, G. W. (technical Coordinator):Recent research on conifer needle di

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1986.tb00213.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY