bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phylogeography of the endangered Eryngium alpinum L. (Apiaceae) in the European Alps
Authors: NACIRI Y. , GAUDEUL M. 
Published: June 2007

AbstractWe studied the phylogeography of Eryngium alpinum by sequencing two intergenic chloroplast spacers, trnH‐psbA and trnS‐trnG (1322 bp). The sampling design included 36 populations and 397 individuals spanning the entire distribution range of the species, from France to Bosnia. Twenty‐one haplotypes were characterized and polymorphism was observed both within and among populations. Population differentiation was strong (FST = 0.92) and largely explained by the distinction of five geographic regions: Southwestern, Western, Middle, Eastern Alps and Balkans (FCT = 0.62). Moreover, NST was significantly higher than GST (P < 0.05), showing the existence of a phylogeographic pattern. Six major lineages were recognized using samova and median‐joining networks. One lineage, highly divergent from the other ones, was only found in the Balkans and probably persisted in situ during last glaciations. All other lineages might have survived in a Southwestern refugium (Mercantour) and colonized the entire Alpine arc (Southwestern, Western, Middle and Eastern Alps) through repeated colonization events at different time periods. This is the first empirical study suggesting Southern refugia for calcareous Alpine plants, although the existence of a secondary refugium in northern Italy/Austria is also suspected. We also observed recent haplotype diversification, especially in the Southwestern Alps.
Hydraulic design of leaves: insights from rehydration kinetics
Authors: ZWIENIECKI MACIEJ A. , BRODRIBB TIMOTHY J. , HOLBROOK N. MICHELE 
Published: June 2007

ABSTRACTWe examined the leaf hydraulic design in 10 species based on their rehydration kinetics. In all cases, a biphasic response described the temporal pattern of water uptake, with time constants of ∼30 to 800 s and ∼800 to 8000 s. The time constants of the fast phase were significantly shorter in the six angiosperms (30 to 110 s) compared with the two single‐veined conifer species (>400 s) examined, while the two multi‐veined gymnosperm species, Gnetum gnemon and Ginkgo biloba, had time constants for the fast phase of ∼150 s. Among angiosperm species, the fast phase constituted 50–90% of the total water absorbed, whereas in gymnosperms 70–90% of the water uptake could be assigned to the slow phase. In the four gymnosperms, the relative water uptake corresponding to the fast phase matched to a good degree the relative volume of the venation and bundle sheath extension; whereas in the angiosperm species, the relatively larger water influx during the fast phase was similar in relative volume to the combined venation, bundle sheath extension, epidermis and (in four species) the spongy mesophyll. This suggests a general trend from a design in which the epidermis is weakly connected to the veins (all four gymnosperms), to a design with good hydraulic connection between epidermis and veins that largely bypasses the mesophyll (four of six angiosperms), to a design in which almost the entire leaf appears to function as a single pool.
Seasonal evolution of diffusional limitations and photosynthetic capacity in olive under drought
Authors: DIAZ‐ESPEJO ANTONIO , NICOLÁS EMILIO , FERNÁNDEZ JOSÉ ENRIQUE 
Published: June 2007

ABSTRACTThis study tests the hypothesis that diffusional limitation of photosynthesis, rather than light, determines the distribution of photosynthetic capacity in olive leaves under drought conditions. The crowns of four olive trees growing in an orchard were divided into two sectors: one sector absorbed most of the radiation early in the morning (MS) while the other absorbed most in the afternoon (AS). When the peak of radiation absorption was higher in MS, air vapour pressure deficit (VPD) was not high enough to provoke stomatal closure. In contrast, peak radiation absorption in AS coincided with the daily peak in VPD. In addition, two soil water treatments were evaluated: irrigated trees (I) and non‐irrigated trees (nI). The seasonal evolution of leaf water potential, leaf gas exchange and photosynthetic capacity were measured throughout the tree crowns in spring and summer. Results showed that stomatal conductance was reduced in nI trees in summer as a consequence of soil water stress, which limited their net assimilation rate. Olive leaves displayed isohydric behaviour and no important differences in the diurnal course of leaf water potentials among treatments and sectors were found. Seasonal diffusional limitation of photosynthesis was mainly increased in nI trees, especially as a result of stomatal limitation, although mesophyll conductance (gm) was found to decrease in summer in both treatments and sectors. A positive relationship between leaf nitrogen content with both leaf photosynthetic capacity and the daily integrated quantum flux density was found in spring, but not in summer. The relationship between photosynthetic capacity and gm was curvilinear. Leaf temperature also affected to gm with an optimum temperature at 29 °C. AS showed larger biochemical limitation than MS in August in both treatments. All these suggest that both diffusional limitation and the effect of leaf temperature could be involved in the seasonal reduction of photosynthetic capacity of olive leaves. This work highlights the need for models of plant growth and ecosystem function to incorporate new parameters affecting the distribution of photosynthetic capacity in canopies.
Two biotypes of Lophodermiul11 pinastri in Scotland
Authors: Millar C. S. , Watson Anne R. 
Published: June 2007

AbstractTwo biotypes of Lophodermium pinastri, perhaps differing in their pathogenicity, were recognised on Pinus sylvestris in NE Scotland. These biotypes are described in artificial culture and are shown to be associated with definite habitats on pines, both in the plantation and in the nursery. In the discussion it is suggested that the present results might help to explain the difficulty many workers have experienced in trying to infect artificially young pine needles with L. pinastri.
Frost injury to Norway spruce during the winter of 1976–1977
Authors: Horntvedt R. , Venn Kåre 
Published: June 2007

AbstractSymptoms of frost injury to young Norway spruce occurred in most of south‐eastern Norway at the beginning of March 1977. Needles and bark of the previous year's and, to a lesser degree, of the two‐year‐old shoots, were affected. The injury was most severe in plantations, especially of southern provenances on high quality sites. There was little or no effect of altitude, terrain or degree of exposure. The injury is presumed to have been initiated by unfavourable weather in 1976 (an extremely dry summer followed by a wet and cold autumn) and triggered by large daily temperature fluctuations towards the end of February when the tissues were lethally injured.
Relative blister rust resistance of white pines
Authors: Hoff R. , Bingham R. T. , McDonald G. I. 
Published: June 2007

AbstractThe frequency of six mechanisms of resistance to white pine blister rust is presented for 18 white pine species. The mechanisms are: prevention of needle lesions, reduced frequency of such lesions, premature shedding of infected needles, a fungicidal reaction in the short shoot, reactions that eliminate established bark infections, and the ability of a seedling to remain alive when infected. The importance of these mechanisms in selecting for resistance in the very susceptible North American white pines is discussed.
Armillaria root rot: Artificial inoculation and development of the disease in greenhouse1
Authors: Singh Pritam 
Published: June 2007

AbstractInoculation of five softwood provenances have revealed that they vary considerably with regard to their percent infection, percent mortality, severity of disease symptoms and progress of infection. Sitka spruce was the most susceptible species and served as a better substrate for further development of mycelium and rhizomorphs as compared to Norway and black spruces and Scots pine. The fungus always entered through uninjured surface of root collar and/or roots, the latter with more than 2 mm diameter. There was a conspicuous reduction m the total and annual growth in height in A. mellea‐infected seedlings.
Conifer root rot studies in the USSR for the years 1976–1978
Authors: Fedorov N. J. , Poleschuk J. M. 
Published: June 2007

AbstractA review is given on current research on Fames annosus and Armillaria mellea in conifer stands in Russia. Investigations are proceeding on a wide front, involving stump treatments, rhizosphere effects and allelopathic effects of various species. Some representative figures for losses are given.
Virulence of Cryphonectria cubensis on Eucalyptus species differing in resistance
Authors: Alfenas A. C. , Jeng R. , Hubbes M. 
Published: June 2007

AbstractVariability in virulence were detected among geographic isolates of Cryphonectria.cubensis (Bruner) Hodges. Inoculation studies of isolates, originally cultured from Brazil, Africa and Hawaii, in provenance of Eucalyptus pellita F. Muell (resistant) and E. saligna Sm. (susceptible) showed that the variation in resistance of Eucalyptus spp. is quantitatively isolate‐specific; the variation in virulence quantitatively host‐specific.The practical consequences of pathogenic variability of C. cubensis and the strategies of selection and breeding of Eucalyptus for resistance is discussed.
Erwinia spp. and a new canker disease of hybrid poplars in Ontario
Authors: Mosseler A. J. , Hubbes M. 
Published: June 2007

AbstractAn attempt is made to determine the cause of a new canker and dieback disease affecting poplar hybrids (Populus spp.) growing in Ontario. Since the disease symptoms appear to be similar to those of a bacterial infection of poplars in Europe caused by Xanthomonas populi Ridé, bacterial species were investigated as possible causal agents of this new disease. Strains of Erwinia herbicola and Erwinia carotovora were associated with branch cankers on affected trees. The hypersensitive reaction on tobacco (Nicotiana tabacum var. Havana) resulting from artificial inoculations of strains of E. carotovora suggests the phytopathogenicity of these strains. Early results from inoculations into rooted poplar cuttings indicated that both strains may be capable of causing discolouration and decay of xylem tissues but these inoculations did not result in canker formation. Both of these opportunistic organisms may be potential pathogens of poplar under certain conditions.
Examination of low‐pathogenicity isolates of Armillaria mellea from natural stands of Picea abies in Middle‐Europe
Authors: Gramss G. 
Published: June 2007

AbstractIn certain indigenous Picea abies Karst. stands in the Thuringian Forest (Middle‐Europe), the incidence of butt rot and die‐back of saplings caused by Armillaria mellea (Vahl ex Fr.) Karst. is conspicuously low in spite of a general spread of this fungus on stumps of clear‐fellings. The majority of 43 isolates of A. mellea recovered from 13 highland infection centres were unable to form the brown type of rhizo‐morphs (BR) in soil but could form the white type rhizomorphs (WR) on sterile substrates. In contrast, 17 isolates from lowland hardwood stands of average disease incidence produced both types of rhizo‐morphs on both substrates. Results of inoculation of excised stem and root sections of Picea abies and Fagus sylvatica L. and saplings of P. abies associated with soils of different fertility levels indicated that the low disease index of certain P. abies stands is caused by the dominance of low‐pathogenicity strains of A. mellea which lack the ability to form BR and penetrate non‐injured bark of roots. Moreover, the poor podzolic highland soil types may contribute more to increase the survival rate and resistance of transplanted P. abies saplings than to reduce the spread of A. mellea.
Untersuchungen zur biologischen Bekämpfung von Heterobasidion annosum an Fichte (Picea abies) mit antagonistischen Pilzen
Authors: Holdenrieder Von O. 
Published: June 2007

AbstractInvestigations on biological control of Heterobasidion annosum in Norway spruce (Picea abies H. Karst.) with antagonistic fungi. I. Production of inoculum and interaction experiments in vitro. Thirty isolates of 22 fungal species were examined in vitro for sporulation, for germination of the spores, and for antagonism of mycelia against three strains of H. annosum. Viable spores were produced by 17 isolates, antagonism was shown by 28 isolates.
Pinus gerardiana—a new host of Arceuthobium minutissimum
Authors: Chaudhry Zakaullah , Badshah Khial 
Published: June 2007

AbstractThe presencs of Arceuthobium minutissimum on Pinus gerardiana in the remperate forests of Dir has been confirmed. It was found in the Zander forests around Anar Killi about 105 km north‐east of Dir. This is the first verified report of A, minutissimum on any host other than Pinus wallichiana.
Effect of bacteria and actinomycetes on germination of conidia of Cylindrocarpon destructans isolates pathogenic to Abies alba and Pinus sylvestris1
Authors: Strzelczyk E. , Rózycki H. , Michniewicz M. 
Published: June 2007

AbstractComparative studies were made on the effect of bacteria and actinomycetes on germination of conidia ofCylindrocarpon destructans. It was found that bacteria, especially strains isolated from the mycorrhizosphere affected germination of conidia stronger than the actinomycetes, although the response of different isolates of the fungus to the action of the strains used was different.
Mycorrhizal symbionts associated with hybrid poplars from Iowa, USA
Authors: Walker C. , McNABB H. S. 
Published: June 2007

AbstractSeven clones of hybrid poplar, with parents from among four sections of the genus Populus, were potted in five Iowan soils. After a year they were sampled for mycorrhizae and endogonaceous spores. Eight species of Endogonaceae were recorded, seven known to form endomycorrhizae. Two ectomycorrhizal fungi, Ccnococcum geophilum and an unidentified species were noted. One poplar clone had fewer replicates in which Glomus fasciculatum spores were found, but otherwise there were no differences among the poplars in presence of spores. A soil from a P. grandidentata woodland had fewer pots with G. mosseae spores, while an agricultural soil had more occurrences of Gigaspora gigantea than other soils. No other significant differences among spores were noted for soils. Vesicles of endomycorrhizae occurred in all clones, but one was colonized more sparsely than the others. Two clones had ecto‐ and ectendo‐mycorrhizae, two types of the former being recorded. One of these clones had significantly more C. geophilum colonization than the other. There were indications of differences in mycotrophy among the sections of the genus Populus.
La variabilité de la sensibilité du Hêtre (Fagus sylvatica L.) à Nectria coccinea, un des agents de la maladie de l'écorce
Authors: Perrin R. 
Published: June 2007

Abstract Variability of Fagus sylvatica susceptibility to Nectria coccinca, one of the agents of beech bark disease. N. coccinea was inoculated into wounds of young beeches raised from seeds of 6 bark diseased trees and 6 healthy ones in the same stand of the forest of Lyons. Classifieation of the progenies, according to the size of the necrosis, is in good agreement with the health of the mother trees. N. coccinca susceptibility of beech has a genetic origin.
Detection of wetwood in living poplar trees by electrical resistance measurements
Authors: Scott Eileen S. 
Published: June 2007

AbstractWetwood was detected in living trees by determining the electrical resistance patterns across the stem with a Shigometer. The resistance of wetwood to a pulsed electric current was low compared with that of healthy sapwood. Bacteria were isolated from wood with low resistance, but rarely from wood with high resistance. Provided that drilling and measurements were performed in a stepwise fashion, the extent of wetwood could be assessed with little damage to the trees tested. This procedure may be useful in identifying trees containing wetwood, particularly in the early stages before crown symptoms become apparent.
Role of periderm in resistance of Eucalyptus marginata roots against Phytophthora cinnamomi
Authors: Tippett Joanna T. , Hill T. C. 
Published: June 2007

Abstract Phytophthora cinnamomi Rands invaded phloem tissue preferentially in Eucalyptus marginata Sm. (Jarrah) roots of both primary and secondary structure. Rate of fungal growth in the “primary” roots was less than in roots with secondary thickening. In the main field study jarrah roots between 1.5–2.5 mm in diameter, were inoculated with P. cinnamomi at regular intervals, over 12 months and in most cases invasion of the phloem was halted within the first 8 weeks of infection. In the majority of roots which exhibited secondary structure, lesion shape reflected the pattern of periderm development. Some lesions were peripheral in the outer phloem as cylindrical periderms had formed close to the vascular cambium. Other lesions were limited to a sector of the roots; periderm had formed radially through the secondary phloem and a zone of suberization was often continuous through the cambial zone and xylem. Formation of periderm at the edge of lesions was a multi‐step process with various changes occurring, including lignification and suberization of walls and accumulation of autofluorescent compounds in cell walls and vacuoles. The layers of suberized and lignified cells formed near lesion fronts, were necrophylactic periderms. Necrophylactic periderm formation generally preceded the establishment of periderm of the exophylactic type.
Factors affecting basidiospore release by Chondrostereum purpureum in New Zealand
Authors: Spiers A. G. 
Published: June 2007

AbstractBasidiospore discharge by Chondrostereum purpureum was studied in the laboratory and in the field.Discharge began several hours. following rain and continued until the water content of sporophores fell below 75%. The duration of the spore release period and the number of basidiospores. released were significantly (P < 0.01) correlated with total rainfall and hours of RH% > 75%. In the laboratory, temperature significantly (P < O.O5) influenced basidiosporc production, the optimum being 18°C. In field studies, temperature correlated poorly with the duration of spore release and the number of basidiospores discharged. Laboratory studies showed that alternating light/dark photoperiods resulted in greater basidiospore production than either conitinuous dark or light, and that due to time lag light stimulated spore production in the dark. Field studies supported rese observations although it was not possible to separate the influence of light from that of relative humnidity and tainfall. Regression equations were derived to predict the amount and duration of spore discharge.
A distribution map for Seiridium cardinale causing the cypress canker disease in Greece
Authors: Xenopoulos S. , Diamandis S. 
Published: June 2007

AbstractThe first distribution map of Seiridium (Coryneum) cardinale (Wag.) Sutton and Gibson which causes the cypress canker in Greece is given. A recent survey all over the country has shown that S. W. Greece and the Ionian islands are already under heavy attack whereas in central and N. Greece and the island of Krete only restricted spots have been found. Strict sanitation measures are imposed to prevent building up and diffusion of the disease.
Ultrastructural aberrations referring to viruses in the needles of young growth disturbed pine seedlings
Authors: Soikkeli Sirkka 
Published: June 2007

AbstractUltrastructural abnormalities in phloem albuminous cells of needles of young pine seedlings from two Finnish nurseries suffering from the growth disturbances of conifer seedlings were studied. Needle samples were taken from growth disturbed seedlings and from healthy looking nursery seedlings as well as from naturally born forest seedlings. The results are discussed in relation to the possibility of virus disease in growth disturbed seedlings. The first trials to observe the viruslike particles from abnormal seedlings will be discussed, too.
The Armillaria species in Europe
Authors: Roll‐Hansen F. 
Published: June 2007

AbstractA literature survey is given of the five European honey mushrooms Armillaria mellea, A. borealis, A. bulbosa, A. cepistipes, and A. obscura (syn. A. ostoyae) (corresponding respectively to Korhonen's intersterile groups D, A, E, B, and C); two forms of A. cepistipes are discussed: the tiny A. cepistipes f. cepistipes from Czechoslovakia and West Germany and the more common A. cepistipes f. pseudo‐bulbosa Romagnesi et Marxmüller. Nomenclature, geographical distribution, hosts, some characteristics, and practical importance (including pathogenicity) are treated.
Long‐term conservation of living fungal pathogens
Authors: Bazzigher G. , Kanzler Esther 
Published: June 2007

AbstractThree simplified freeze drying methods have proved partieularly successful for the long‐term conservation of phytopathogenie fungi. Tests revealed no loss of vitality after up to 25 years of storage. The determination of the maximum lethal temperature allows the storage life of lyophilised fungi to be estimated.
Sustématique des Armilaires du groupe Mellea. Conséquenmces phytopathologiques
Authors: Guillaumin J.J. , Lung Brigitte , Romagnesi H. , Marxmuller Helga , Lamoure Denise , Durrieu G. , Berthelay Stizanne , Mohammed Caroline 
Published: June 2007

Abstract The systematics of the Armillaria mellea complex. Phytopathological consequences. The five biolo‐gical species of the Armillaria complex as defined by Korhonen coincide with species already defined by other authors on the basis of their morphology and have been given latin namenelature.The main characteristies of the five Eurmpean species are deseribed: Fruitbody morphology, myce‐lium morephology in loboratory culture, rhizomorphs grown in a rhizotron and the ease with which fruithodies are produced in the laboratory. A descriptiom is given of the geographical distribution ecological specialisation and pathogenicity of these 5species.
A preliminary note on Phellinus noxius root rot of Cordia alliodora plantings in Vanuatu
Authors: Neil P. E. 
Published: June 2007

AbstractThe results of a preliminary survey to evaluate the impact and distribution of root disease caused by Phellinus noxius (Corner) G. H. Cunn. in enrichment plantings of the introduced tree Cordia 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.
Pathogenicity of Leptographium procerum and L. terebrantis on Pinus strobus seedlings and established trees
Authors: Wingfield M. J. 
Published: June 2007

AbstractThe pathogenicity of Leptographium terebrantis and Leptographium wageneri, was compared with that of eight isolates of L. procerum from different parts of the world by wound inoculation of two‐year‐old Pinus strobus seedlings. Isolates of L. procerum caused limited discoloration around inoculation sites whereas L. terebrantis caused girdling cankers and L. wageneri systemically invaded seedlings. Only three of 160 seedlings inoculated with various isolates of L. procerum died; L. terebrantis and L. wageneri killed 17 and 15 of 20 seedlings inoculated respectively. Inoculation of L. procerum and controls caused localised discoloration around inoculation points and inoculation with L. terebrantis resulted in lesions up to 150 cm long on 15‐year‐old P. strobus. Lesions associated with L. procerum were however significantly longer than the discolored areas on control plants. In comparison with L. terebrantis, L. procerum appears to be a weak wound pathogen.