摘要:

AbstractIn a bare‐root nursery we have determined the incidence of soil fumigation and mycorrhizal inoculation on survival growth and ectomycorrhizal development of Norway spruce and Douglas fir seedlings. Three experimental designes were installed in 1978, 1981 and 1982.Soil fumigation eliminated or reducedRbizoctonia solani, Pytbiumsp. and probablyFusarium oxysporumpropagules. Fumigation improved Norway spruce seedlings performance, particularly in the second year. Douglas fir seedlings seemed less sensitive to soil‐borne pathogens tha Norway spruce seedlings.Two years after inoculation,Hebeloma cylindrosporumincreased Norway spruce growth by 40% and Douglas fir growth by 30 % in comparison with seedlings grown in fumigated soil and mycorrhizal with the naturally occurring fungusThelephora terrestris.Both, fumigation and artificial inoculation increased Norway spruce seedling growth by 110 % and Douglas fir seedling growth by 5

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1986.tb00190.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractThe influence of various SO2concentrations was investigated on the process of metabolites transport, particularly on the translocation of total and free sugars in SO2‐sensitive and SO2‐tolerant seedlings of Scots pine. It was observed that regardless of the SO2concentration used and the duration of time since the termination of fumigation the transport of14C‐products underwent stronger disturbances due to the action of SO2than14CO2uptake. Inhibition of the transport of14C‐sugars led to a decrease in the quantity of sugars supplied from the needles to the roots but it did not affect the qualitative composition of the transported sugars. These disturbances were greater in the SO2‐sensitive seedlings than in the tole

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1986.tb00191.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractThe results of a preliminary survey to evaluate the impact and distribution of root disease caused byPhellinus noxius(Corner) G. H. Cunn. in enrichment plantings of the introduced treeCordia alliodora(Ruiz. and Pav.) Oken in the natural forest of Vanuatu show that the overall impact of the disease is light with some slight increase with increase in age of crop. On Pentecost Island losses are much more severe, increasing rapidly in older plantings. The high level is thought to be due to the interaction of relatively high rainfall and high inoculum level in the natural forest. Further studies and surveys of the disease are planned.

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1986.tb00192.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractBacteria of the genusPseudomonaswere screened for antagonistic activity towardsCeratocystis ulmi in vitro. Selected bacteria were then tested for their ability to suppress symptoms of Dutch elm disease in English elm (Ulmus procera) and Commelin elm (U. Xhollandica“Commelin”)in vivo. In a series of preventative bacterial injection experiments on English elm, no reduction in disease levels was obtained by comparison with non‐injected controls. In curative injections of Commelin elm, only a slight reduction of disease recurrence in treated trees was indicated. Bacteria showed limited upward distribution in the trees, but may have become well distributed within the roots. The significance of the results for the control of Dutch elm disease is disc

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1986.tb00193.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractGrafts of sensitive and tolerant eastern white pine (Pinus strobusL.) clones were exposed to extended (week‐long) low levels (5 pphm) of sulfur dioxide (S2O), ozone (O3), and their combination in order to observe effects on photosynthesis. Consistent but statistically non‐significant increases in photosynthesis over the week were noted in all tolerant clones and in all but one sensitive clone when fumigated with SO2or SO2+O3. Likewise, O3consistently depressed photosynthesis in both tolerant and sensitive clones. There were significant differences in response between tolerant and sensitive clones fumigated with O3, and in the response of tolerant clones fumigated with O3versus those in SO2

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1986.tb00194.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractThe pathogenicity ofLeptographium terebrantisandLeptographium wageneri, was compared with that of eight isolates ofL. procerumfrom different parts of the world by wound inoculation of two‐year‐oldPinus strobusseedlings. Isolates ofL. procerumcaused limited discoloration around inoculation sites whereasL. terebrantiscaused girdling cankers andL. wagenerisystemically invaded seedlings. Only three of 160 seedlings inoculated with various isolates ofL. procerumdied;L. terebrantisandL. wagenerikilled 17 and 15 of 20 seedlings inoculated respectively. Inoculation ofL. procerumand controls caused localised discoloration around inoculation points and inoculation withL. terebrantisresulted in lesions up to 150 cm long on 15‐year‐oldP. strobus. Lesions associated withL. procerumwere however significantly longer than the discolored areas on control plants. In comparison withL. terebrantis,L. procerumappears to be a weak wound p

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1986.tb00195.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractDamping off in forest nurseries. A survey of conifers damping off in French nurseries revealed that the principal pathogens involved wereFusarium oxysporum, Pythiumspp. andRhizoctonia solani. Larch, spruce, and pines in general were most susceptible host species. No correlation was observed between disease severity and causal agents involved with factors such as sampling year, host species, seedling age, and location of nurseries. The disease intensity, independant of soil type, was mainly related to local weather conditions prevailing at the period of seedling emergence.Disease prediction and preventive treatment were difficult to realize in practice. Improved control measures could be expected from a better understanding of disease epidemiology.

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1986.tb00196.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractA new embedding system for histological studies of conifer needles. Preparation of conifer needles for lightmicroscopic investigations has been difficult using conventional methods due to density gradients within the tissue. A new embedding system with glycol‐methacrylate (GMA) is described which provides a structural conservation of sections as thin as 1 μm. A large variety of histological staining procedures can be applied to the tissue without removing the plastic compou

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1986.tb00197.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractOccurrence of four disease of foliage viz. two leaf spots, one leaf blight and a web blight caused byColletotrichum capsici, Cercospora subsessilis, Sderotium rolfsiiandRhizoctonia solanirespectively and one each of stem (stem rot byS. rolfsii) and root (wilt byFusarium solani) are reported for the first time on seedlings ofAzadirachta indicafrom Kerala, India. Leaf spots though widespread did not cause much damage to seedlings, while the other diseases resulted in ca. 20–30 percent mortality, thus affecting the stockin

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1986.tb00198.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractThe humidity response of individual twigs was determined in “clean” air and subsequently during exposure to SO2(0.3 to 0.05 ppm). Changes in regression were related to the effect of SO2on stomatal movement.In short‐term experiments, the response of the twig to SO2varied with the prevailing humidity of the air. During long‐term fumigations there were three distinct behavioural phases, a first with suppressed, a second with high, but erratic transpiration eventually followed by low rates and visible symptoms of

ISSN:0300-1237    

DOI:10.1111/j.1439-0329.1986.tb00199.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY