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1.
In 2017, severe symptoms of brown spot needle blight, similar to those caused by Lecanosticta acicola, were observed on needles of non‐native Pinus mugo var. Hesse planted in an arboretum in southern Sweden. Microscopic characterization and molecular diagnostics of isolates obtained from diseased needles confirmed the identity of L. acicola. This is the first report of the quarantine pathogen L. acicola in Sweden. Subsequent surveys are urgently needed to assess the presence and extent of the L. acicola invasion in Scots pine (Pinus sylvestris) stands in Sweden and other Scandinavian countries.  相似文献   

2.
Lecanosticta acicola (Thüm.) Syd., a serious foliage pathogen of pines in many regions of the world, is an emerging invasive species in northern Europe. After the first record of L. acicola on Pinus ponderosa Dougl. ex Laws. in northern Estonia in 2008, monitoring was started to investigate the spread and host range of the fungus in the country. By the beginning of 2015, L. acicola was also recorded on P. uncinata Mill. ex Mirb., P. mugo Turra and on P. mugo var. pumilio (Haenke) Zenari, being the northernmost records of the fungus in Europe. So far, the single native pine species Pinus sylvestris L. has not been found to be infected. Molecular analysis proved infection of L. acicola on pines in five different localities of Estonia: in Tallinn (mainly in the Botanic Garden, northern Estonia), in Tori and Kärdla (western Estonia), in Vasula and Kärevere (east-central Estonia). The sexual state (teleomorph) of the fungus was not found, but the existence of the both mating types, MAT1-1 and MAT1-2, was confirmed.  相似文献   

3.
Brown-spot needle blight caused by Mycosphaerella dearnessii [syn. Scirrbia acicola; anamorphic state: Lecanosticta acicola (syn. Septoria acicola)] was observed for the first time in Switzerland. So far, the disease seems to be confined to planted Pinus mugo and Pinus uncinata near Zurich. Pinus sylvestris adjacent to diseased P. uncinata did not show any disease symptoms.  相似文献   

4.
Plant lesions affect disease impact, progression and host resistance. Root lesions caused by Armillaria ostoyae (Romagn.) Herink were inspected on 24‐ to 34‐year‐old planted Douglas‐fir (Pseudotsuga menziesii (Mirb.) Franco) pulled from the soil in five locations. Four hundred seventy‐nine lesions were measured for length (mm), expansion rate (mm/year) and lesion type. Lesion types were patch lesions on a root side, girdled lesions covering the root circumference and root collar lesions on the stem below ground. Non‐linear mixed modelling revealed that fungal lesion length at girdled and collar lesions increased but the expansion rate slowed as a power function of time, indicating increasing secondary inoculum and host resistance. Average fungal lesion expansion rate in girdled root and collar lesions was 127 mm the first year which then declined non‐linearly to 26 mm/year after 10 years. Fungal lesion length in patch lesions showed little change after the first year of infection. For girdled and collar lesions, fungal lesion length increased with tree size at the time of infection. Sites with a longer frost‐free period had shorter girdled root and stem lesions, probably because of more active host defence. Results indicate that mortality would be rare from one infection event. Furthermore, patch lesions pose a lower risk of mortality than other lesions because of a lower fungal lesion expansion rate and secondary inoculum. Tree size, lesion position, lesion type and fungal lesion expansion rate need to be considered when assessing the risk of lesions to individual tree survival. Techniques to minimize the disease impact are discussed.  相似文献   

5.
The formation and maturing of the large tree type Gremmeniella abietina var. abietina fruiting bodies and their sporulation were investigated for 3 years on Scots pine (Pinus sylvestris) in northern Finland. This was done by monthly assessment of shoots in the field and in the laboratory. Infection caused by G. abietina var. abietina was dated on Scots pine by monthly covering with pollination bags and exposing branches during the growing season. Pycnidia appeared between August and September, 1 year after infection, and they started to release conidia between late June and early July, 2 years after infection. Fresh pycnidia and microconidia were formed during the following August and September in the infected shoots. The causal large tree type of G. abietina var. abietina did not produce apothecia on branches within 3 years of infection. Monthly covering and exposing branches showed that infection took place mainly between June and July.  相似文献   

6.
Falling needles collected from under individual 70-year-old Norway spruce (Picea abies) trees for about four years were checked for fungal fruitbodies. The most common fungi were Lophodermium piceae and Rhizosphaera kalkhoffii. Maximum frequencies of fruitbodies occurred in late autumn for L. piceae (ca. 80% of the needles), in summer for R. kalkhoffii (ca. 60%) and in winter for the third most common fungus, Tiarosporella parca (ca. 10%). The frequencies of needles with fruiting fungi varied greatly within and between years. This is the first report of T. parca from Sweden.  相似文献   

7.
A historical outbreak of needle blight disease was recorded during 2018 to 2019 in plantations of Pinus radiata and Pinus nigra in the North of Spain. The main pathogens involved in this historical outbreak were identified as Lecanosticta acicola and Dothistroma septosporum. Recently, a variety of tree species in three arboreta planted between 2011 and 2013 in the Basque Country as part of the European project REINFFORCE were showing symptoms of needle blight and defoliation. The aim of this study was to determine which pine species were affected with these pathogens. Tree species sampled included several provenances of P. brutia, P. elliottii, P. nigra, P. pinaster, P. pinea, P. ponderosa, P. sylvestris and P. taeda. Using molecular identification methods, Lecanosticta acicola was confirmed infecting Pinus brutia (Provenance: Alexandropolis, Greece and var. eldarica, Crimea) and represents a new host species for this pathogen. Pinus elliottii (Provenance: Georgia, USA) and P. ponderosa (Provenance: Central California, USA) are new host reports of L. acicola for Spain. Dothistroma septosporum was found for the first time on P. brutia (Provenance: Marmaris, Turkey) and P. ponderosa (Provenance: Oregon, USA) in Spain and was also detected infecting P. nigra (Provenance: Sologne Vayrières, France).  相似文献   

8.
北美鹅掌楸人工林生长规律及早期选择可行性探究   总被引:1,自引:0,他引:1       下载免费PDF全文
[目的]北美鹅掌楸为优良的珍贵用材树种,研究其生长发育规律及生长性状早晚期相关对于北美鹅掌楸人工林高效培育有重要的指导意义。[方法]本文利用树干解析的方法对江苏句容24年生的北美鹅掌楸人工林生长规律研究,并在此基础上进行胸径、树高和材积性状的年年相关分析以及早期选择效率评价。[结果]研究结果表明:北美鹅掌楸胸径、树高从6 a进入快速生长期,持续到17 a,而材积则在1 10 a增长缓慢,12 a后进入速生期,生长速率在20 a达到最大,22 a后逐渐降低,林分接近数量成熟。生长性状的年年相关及早期选择效率分析结果表明:胸径、树高在6 a与18 a显著相关,材积在6 a与16 a达到显著相关,且此时选择效率最高;若以24 a为伐期年龄早晚相关分析,胸径、材积在16 a与24 a生长量达到显著相关水平,而树高则为14 a。[结论]北美鹅掌楸胸径、树高早期增速较快,进入中壮龄阶段竞争加剧,个体间分化增大。随着林分年龄的增长,研究获得的早期选择年龄也相应地延迟。从加速育种角度,在6 a进行早期选择较为合理,而在培育大径材北美鹅掌楸方面可以16 a之后再进行疏伐选择。  相似文献   

9.
Commercial harvesting of matsutake in Finland has driven the need to understand how fruiting is affected by climate and habitat. A productive site in Finland was studied in this respect. Productivity, duration, and early onset of fruiting were examined in relation to mean air temperature, soil temperature, accumulated degree-days, and precipitation. We monitored the fruiting of matsutake and other macrofungi during 2008–2013. As a pilot study, our results showed the timing and yield of the annual fruiting of Tricholoma matsutake varies in Southern Finland and can occur from the middle of July to middle of September; although we did not find a clear and simple correlation between fruiting and rainfall, an average amount of precipitation (i.e. 90–110% of the long-term average precipitation) prior to the first fruiting was associated with high yield; we did not identify any threshold soil temperature associated with the onset of fruiting, however, we found that soil temperature might provide a means to monitor the end of the matsutake fruiting period, and late onset or higher soil temperatures prior to the first fruiting were associated with shorter fruiting periods. These results can be further utilized for developing a model to predict the yield of T. matsutake in Nordic regions.  相似文献   

10.
The structural changes in the cell wall and delignification pattern caused by Trametes versicolor and Trametes hirsuta in the sap wood of Leucaena leucocephala were examined by light and confocal laser scanning microscopy. The in vitro decay test was conducted for 12 weeks. Both species of Trametes used in this study caused anatomical characteristics specific to simultaneous white rot. Formation of boreholes, erosion troughs, erosion channels with U-shaped notches in tangential sections and thinning of cell walls were evident in the wood inoculated with each of the fungal species. Cell separation due to removal of middle lamellae occurred at the early stages of infection (30 d) with T. versicolor. In contrast, middle lamellae remained intact in wood inoculated with T. hirsuta and showed cell separation due to degradation of the outer layer of the secondary wall and degradation of the middle lamellae observed only in severely decayed wood at late stages. Confocal microscopy revealed the delignification pattern particularly from cell corners and vessel walls at an advanced stage of decay, indicating strong ligninolytic activity of both species in the sapwood of L. leucocephala.  相似文献   

11.
Results obtained in the monitoring of stored tobacco pests by pheromones are reported. In GreeceEphestia elutella (Hübner) is likely to have at least 3 generations per year: the first one appears in early May, the second one during the last week of June and the third one— the most populated and the longer lasting—in August. In the same environmentsPlodia interpunctella (Hübner) has shown about 5 generations per year. The first on appeared in late May; the remaining 4—definitely overlapping—are placed in mid-June, in July, in early August and early September. In Italy four commercial pheromone dispensers effective in trappingLasioderma serricorne Fabricius have been compared. The results pointed out highly significant differences of the efficacy of the four different dispensers tested.L. serricorne was present in the tobacco store from June to October with a quite remarkable increase between August and early September.  相似文献   

12.
The connection between natural conidia dispersal of Gremmeniella abietina (A‐type) and the disease incidence and severity in first and second year conifer seedlings of Pinus sylvestris was studied in central Finland. The seedlings where exposed to natural infection for a 3‐week period throughout the growth season, followed by a 3‐week incubation period in a growth chamber to promote symptom expression. In second year seedlings the infection periods in May–June had a similar effect as regards disease outbreak and roughly half of the successful infections occurred during these periods. However, the first year seedlings were more severely diseased after the infection period in late July/early August, although the inoculum density was lower during this time compared with the period in late June/early July. This result is consistent with earlier studies. The effect of age and growth phase of the seedlings, temperature sum and the number of conidia on the disease occurrence is discussed and compared with the results of earlier studies in which artificial inoculation was employed.  相似文献   

13.
The presence of quarantine pathogen Lecanosticta acicola, the causal agent of brown spot needle blight, was confirmed using molecular methods for the first time in northern part of Poland on the coastal area adjacent to the Baltic Sea. This area includes sandy beaches, where Pinus mugo and P. sylvestris were planted. Symptomatic needles were collected in 2017 from 20 P. mugo trees growing in one stand in Ustka. Typical symptoms of brown spot needle blight infection, including dead needle tips and central zones with yellow or reddish brown, circular spots in green tissue, were observed on all samples. Only, the asexual stage of L. acicola was obtained during this work. The pathogen species identity was confirmed using classical morphological methods (microscopic examination of the infected needles), real‐time and species‐specific priming (SSPP) PCR, and ITS sequencing. Analysis of mating‐type (MAT) genes showed the presence of both mating types in northern Poland.  相似文献   

14.
Four‐year‐old seedlings of Abies nordmanniana ssp. bornmülleriana and 5‐year‐old seedlings of Abies nordmanniana ssp. nordmanniana were inoculated on the lower stem with 28 Heterobasidion abietinum isolates originating from four different regions of Turkey. Replicate seedlings were incubated in greenhouse and growth chamber. After 7 weeks, infection incidence, mortality, lesion length in the inner bark and fungal growth in the sapwood were examined. Infection incidence in different host–incubation combinations ranged between 70.5 and 79.5% and the average mortality rate was 4.2%. Average lesion lengths varied between 8.4 and 33.9 mm, and average fungal growth between 18.7 and 34.8 mm. There was a significant positive correlation between lesion length in the inner bark and fungal growth in sapwood on both hosts and conditions. Clear differences in virulence between H. abietinum isolates originating from different regions were not found. The results indicate that H. abietinum is pathogenic on both investigated subspecies of A. nordmanniana. Both lesion length and fungal growth were greater on ssp. bornmülleriana, indicating that it would be more susceptible than ssp. nordmanniana.  相似文献   

15.
To examine the effect of the spatial distribution of litter and intergeneric interaction on the spatial distribution of agaric fruiting bodies, we surveyed spatial distribution of fruiting bodies of Agaricales in a mixed forest dominated by Pinus densiflora (Sieb et Zucc.) from July 1999 to July 2002. Three 10 × 10-m plots with different vegetation and positions on a slope were established: Top-Mixed, Top-Pinus, and Bottom-Pinus. Litter thickness in the Top-Mixed plot was the thinnest among the three plots. During the study, we counted 3563 fruiting bodies in 27 genera from 13 families. The dominant genera were Collybia, Marasmius, Mycena, Rhodophyllus, and Lactarius, and showed an intrageneric aggregated distribution at a quadrat size of 1 m2. Collybia and Lactarius formed fruiting bodies in arcs. The spatial distribution of Collybia, Marasmius, and Lactarius fruiting bodies tended to overlap in two consecutive years. In the Top-Mixed plot, the number of Marasmius fruiting bodies increased with increasing litter thickness, while that of Lactarius decreased with litter thickness. Values of Cδ indicating degree of overlap were calculated for particular pairs of dominant fungal genera and the values differed between plots and years: for example, fruiting bodies of Marasmius and Mycena in the Bottom-Pinus plot were distributed aggregately in 1999 and 2000, but randomly in 2001, while they were distributed segregatedly in the Top-Pinus plot every year. Our study suggests that the spatial distribution of fungal fruiting bodies is affected by the distribution of litter in and between plots and that fungal flora is affected by vegetation.  相似文献   

16.
Pinus greggii Engelm. ex Parl. is an endemic pine of Mexico with notorious adaptability to eroded, shallow and poor soils. It is widely used in reforestation programmes worldwide. The purpose of the present study is to develop an ectomycorrhizal fungi (ECM) treatment with different native ectomycorrhizal fungal species (collected in P. greggii and Abies vejarii stands) to improve seedling survival of P. greggii. Four-month-old P. greggii var. greggii seedlings were inoculated with ground fruiting bodies of the ECM species Astraeus spp., Boletus barrowsii, Geastrum minimum, Lactarius deliciosus var. deterrimus, Russula cf. atroglauca, Russula spp., Suillus caerulescens, as well as a mixture of three species (Russula sp., R. lutea and L. deliciosus) and soil litter with mycelium from the base of a fruiting body of L. deliciosus. Agronomic variables, and total phosphorous and glucosamine contents were measured in P. greggii seedlings. Inoculated treatments with B. barrowsii, Geastrum minimum and S. caerulescens showed increases in seedling height and basal diameter as well as dry shoot biomass compared with those of the control plants. Geastrum minimum, B. barrowsii and R. xerampelina significantly increased values of dry weight compared with that of the control. Inoculation of soil litter from the base of a fruiting body of L. deliciosus induced the maximum glucosamine response (40.2 mg g?1 of dry root biomass). Geastrum minimum, a fungus collected in P. greggii stands, enhanced basal diameter of pine seedlings in the nursery. Fungal species B. barrowsii, Suillus caerulescens, Russula cf. atroglauca and Russula spp. from the Abies forest improved plant quality in terms of the Dickson quality index and root and shoot biomass, compared with those of the control.  相似文献   

17.
First record of Lophodermella sulcigena in Poland . Lophodermella sulcigena (Rostr.) v. Höhn. has been recorded from Pinus sylvestris in Poland. Disease symptoms, morphology of the fungus and possible predisposing factors are described.  相似文献   

18.
The susceptibility of oak seedlings (Quercus palustris, Quercus robur, Quercus rubra) and chestnut seedlings (Castanea sativa) to Phytophthora cinnamomi was tested. The dynamics of infection was examined in plant material raised in a rhizotron. In the oak species, primary root tissues were susceptible whereas secondary cortical tissues showed some resistance to P. cinnamomi. Secondary cortical tissues of the tap root in C. sativa were susceptible. Inoculations with P. cinnamomi were performed both in situ and on excised roots of mature Q. rubra. In both cases, the resistance of Q. rubra roots and shoots was negatively correlated with diameter at the inoculation point. Small roots (l–5-cm diameter) were resistant, whereas collar and trunk were susceptible. In contrast to oak, small excised roots of mature C. sativa (0.7–2-cm diameter) were susceptible to P. cinnamomi. This may explain why P. cinnamomi does not induce a decline of the attacked oaks, but rather a trunk canker.  相似文献   

19.
Dothistroma and Lecanosticta needle blight are among the most damaging foliage diseases in plantations and natural pine stands worldwide, and are therefore listed as quarantine organisms in numerous countries. The aim of this study was to validate different methodologies used for the detection of both diseases. Based on multiplex quantitative PCR (qPCR), simultaneous detection and discrimination of the three pathogens Dothistroma septosporum, Dothistroma pini and Lecanosticta acicola were possible in symptomatic needles. Additionally, the same set of needles was analysed for the presence of all three pathogens using novel end‐point PCR assays followed by enzymatic digestion of PCR products. Results were compared with the qPCR data, and for validation, collected needles were screened morphologically for the presence of typical fruiting bodies and spores. Differences in detection sensitivity were found between the detection tools. The qPCR‐based detection allowed for specific and efficient identification and quantification of all three pathogens simultaneously. At the same time, conventional PCR assays, which target the multicopy ITS region, showed increased detection sensitivity and can be conducted without the use of expensive infrastructure and reagents.  相似文献   

20.
The Périgord black truffle (Tuber melanosporum Vittad.) can mycorrhize with rockroses (Cistus L.) in Mediterranean forests. These shrubs may be of interest for truffle cultivation as they produce early carpophores, collaborate in tree mycorrhization and in the survival of Tuber melanosporum mycelium. However, there are very few quantitative studies on truffle production associated with Cistus. For this reason, we have carried out a study on the natural production of Tuber melanosporum associated with Cistus laurifolius L. in central Spain. An Anova test confirmed the existence of significant differences in carpophore production in four habitats, with and without the presence of C. laurifolius. Twenty-one burns associated with C. laurifolius showed less significant production than the rest. We also confirmed that in 122 burns, Tuber melanosporum was always unequivocally associated with the root base of Quercus L. or Corylus L. trees. Similarly, five truffle-collectors confirmed that they had never found a single burn with carpophore production associated exclusively with rockroses. It has also been statistically verified that many Cistus die in Tuber melanosporum burns, whereas in old burns with minimum carpophore production, a new colonization of young Cistus has been observed. This study also confirms that C. laurifolius mycorrhizes easily with Tuber melanosporum. We propose that Cistus laurifolius may act as transmitters of Tuber melanosporum, although they do not induce fruiting. Consequently, the commercial cultivation of Cistus laurifolius mycorrhized with Tuber melanosporum for production is not recommended in truffle culture. The results reported substantiate the negative observations in cultivations of T. melanosporum with other Cistus species.  相似文献   

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