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We describe the ectomycorrhizal (ECM) root tips and the diversity of mycorrhizal fungal species at three English oak (Quercus robur) sites (two 120 year old sites and one 60 year old site). The three oak stands in decline, located in western Poland, were characterized by a low degree of vital ECM colonization: 30.2%, 29.1% and 25.6% at Krotoszyn (K), Piaski (P) and Karczma Borowa (KB), respectively. DNA (ITS) barcoding revealed a total of 18 ECM fungal species. Based on exploration types, ectomycorrhizae were classified with respect to ecologically relevant features. The contact type was significantly correlated with C:N and Corg, while the short distance type was correlated with Ca, phosphorus (P2O5) and pH. The medium distance exploration type was significantly correlated with fine-grained soil particle size fractions: coarse silt (0.05&ndash, 0.02 mm) and fine silt (0.02&ndash, 0.002 mm), and clay (&lt, 0.002 mm). The long distance type showed a similar pattern to the medium distance smooth type, but was also correlated with nitrate (N). The values of biometric root parameters of oak trees at the analysed forest sites were arranged as follows: K &gt, P &gt, KB, and were opposite to the condition of the tree crowns. A negative correlation of vital ECM root tip abundance with the crown health status of oaks was observed, whereas higher ECM diversity reflected better crown health in the oak stands studied.

Producción Científica, The fungal pathogen Fusarium circinatum is the causal agent of Pine Pitch Canker (PPC), a disease which seriously affects different species of pine in forests and nurseries worldwide. In Europe, the fungus affects pines in northern Spain and Portugal, and it has also been detected in France and Italy. Here, we report the findings of the first trial investigating the susceptibility of Polish provenances of Scots pine, Pinus sylvestris L., to infection by F. circinatum. In a greenhouse experiment, 16 Polish provenances of Scots pine were artificially inoculated with F. circinatum and with six other Fusarium species known to infect pine seedlings in nurseries. All pines proved highly susceptible to PPC and displayed different levels of susceptibility to the other Fusarium spp. tested. The findings obtained indicate the potentially strong threat of establishment of an invasive pathogen such as F. circinatum following unintentional introduction into Poland., Fund of the Forest Research Institute (Poland) through Grant No. 240327, Ministry of Education and Science of Ukraine within joint Ukrainian-Lithuanian project No. M/93-2018, Portuguese Foundation for Science and Technology (FCT) (grant-SFRH/BPD/122928/2016)

Climate change and food security: challenges for plant health, plant breeding and genetic resources

The Capillary Electrophoresis (CE) is one of the method widely used in modern molecular genetics, applied for fast and efficient DNA fragment separation in the sieving polymer in the electric field [1]. The use of this method has increased dramatically over the last fifteen years, due to high precision of small nucleic acid separation (even to the singe nucleotide level) of the available material analysed in the field of analytical chemistry, physical chemistry, biochemistry, and biotechnology. Essentially, the CE technique has been used for genome sequencing projects, e.g. Human Genome Project [2] or many others assignments (for animals, plants, bacteria and fungi), published in NCBI database (www.ncbi.org).

Precise identification of biological samples remains the most important proof in the forensic science. Illegal logging has become the urgent issue in Poland during the last decades, and conventional methods of investigation turn out to be often insufficient. Recently, the DNA-based markers (SSR and cytoplasmic genes) can remarkably help in the forensic botany performed by the Forest Service Guards and the Police investigation in illegal logging of timber. The identification method relies on comparison of the piece of evidence (i.e., stolen wood fragments) with the piece of reference (e.g., tree parts remained in the forest). We present the usefulness of the DNA neutral markers (i.e., microsatellite loci) and cytoplasmic genes in forensic botany based on several case studies of illegal wood identification in Poland, concerning the most economically important coniferous tree species such as Pinus sylvestris L., Picea abies (L.) Karst., Abies alba Mill., and Larix decidua (L.). Thanks to the DNA profiles established on the basis of minimum 4 microsatellite nuclear DNA loci, and at least one cytoplasmic organelle (mitochondrial or chloroplast) DNA marker, the determination of the DNA profiles provided fast and reliable comparison between material of evidence (also wood and needles) and material of reference (first of all tree stumps) in the forest. These data strongly supported the decision taken by several District Courts in Poland, as far as the identification of wood samples was proved with a high probability (approximately 98–99 %). The aim of the below publication is to present Polish case study on DNA use to fight illegal logging which became very successful among foresters.

Dothistroma septosporum (Gremmen & Morelet) is an economically important fungal disease that affects needles of conifers, in particular pines. Nowadays, over 60 tree species have been reported to be susceptible to infection, among them Pinus nigra (Arn.), P. brutia (Ten.), P. pinaster (Ait.), P. pinea (L.), P. mugo (Tur.) and P. sylvestris (L.) are the most susceptible in Europe. The discovery of dothistroma needle blight (DNB) dates from 1933 in Spain, 1971 in Slovenia, 1980 in Greece, 1985 in Scotland, 1986 in Serbia, 1995 in Poland, 1996 in Slovakia, 1999 in Czech Republic, 2002 in Lithuania, 2006 in Estonia, 2007 in Finland and Sweden, 2008 in Latvia and Russia, 2009 in Norway. Recently, some data of newly infected Larix spp., Abies spp. and Picea spp. by Dothistroma sp. have been reported from Lithuania, Latvia, Serbia and Macedonia. The exact origin of the disease is unknown, although it is suggested that it might be originated from the pine forests in Nepal, India and Pakistan, or also from the high altitude rain forests in South America. It is believed that the disease has been prevalent in the southern hemisphere before reaching high levels of infection in the northern hemisphere, with unprecedented records of the disease in Asia, Europe and the UK. In general, the spores of Dothistroma spread initially in moist conditions (through mist and rain), or by direct contact with other infected needles. Once the needles have been exposed to spores, the fungus germinates in wet conditions, followed by needle penetration through stomata. The optimal germination temperature is 12–18°C, with high level of humidity. The needles soon turn to reddish discoloration and on their the pathogen produces eventually the pycnidia, which are the pathogen’s fruiting body. The pycnidia are formed in the spring and early summer, and usually coincide with high level of precipitations.

Never before in the history, the invasion of the alien pest had been so numerous, causing important finan-cial losses, and at the same time EU countries had faced the lack of efficient tools to control them. The concern of public health became an urgent issue, livelihoods of growers are threatened, and export markets exposed at high risk, if policies for mitigating the pest impact are not being urgently modernized. Nowadays, these prob-lems are increasing because the ability of exotic species to invade virtually all regions of the word has been ac-celerated by global climate change, increased interna-tional travel, and on-going difficulties of detection in early invasion stages. Consequently, invasive pest and pathogen problems have not only begun to place grow -ers and commodity exporters in many countries at great financial risk, but have also stretched to the limits the capabilities of regional, national and international regu-latory agencies for dealing with them.Because of the ever-increasing numbers of in -sect pests that are invading importing and exporting countries throughout the word, a three-day mini-symposium and workshop entitled “Opportunities for enhancement of integrated pest management” were held in April 1–3, 2014 at Warsaw University of Life Sciences (SGGW), involving 45 prominent entomolo -gists, plant pathologists, invasion biologists, and pol -icy advisers. Among different topics of a symposium, the induced plant resistance, functional biodiversity, the role of ecological infrastructures and invasive (al -ien) pests and natural enemies, as well as perspectives and bottlenecks in manipulation of insect behaviour for enhancement of integrated pest management (IPM) were discussed. The workshop dealt with implication of biodiversity in genetically modified plants, and with on-farm behaviour of European cherry fly (

Shoot and root fresh and dry matters and their Cu content were determined in 7-d-old seedlings of Triticum aestivum L. cv. Alkora treated with Cu (10,20, 40 µg cm-3) and Si (500 µg cm-3). Si significantly reduced the toxic effect of Cu on fresh and dry matter production of wheat seedlings. Moreover, plants treated with Cu and Si absorbed less Cu from the solution and had higher water content in shoots and roots than that treated with Cu only.

Slow Sand Filters (SSF) are a biological method used to protect nursery plants, from pathogen infections which can cause serious diseases in many forest tree species. Thanks to SSF application the number of phytopathogens in nurseries can be significantly reduced, as demonstrated by many field and greenhouse experiments (e.g. in Polish nurseries, and for horticultural crops in Germany and The Netherlands). In this study, the effect of pollution from fertilizers and fungicides used in agriculture (e.g. PCNB) on the efficiency of SSFs was assessed. A quantitative analysis was performed of the copiotrophic and oligotrophic bacterial composition colonizing SSF biofilms. The efficiency with which selected Oomycete strains belonging to the genus Phytophthora (P. alni, P. cactorum, P. plurivora) were removed from water was determined based on genetic material (DNA of the organisms) found in the SSF filtrate. Specific primers and TaqMan probes (qPCR) appeared to be the most sensitive molecular methods. Moreover, the microbiological analysis of SSF biofilm performed with selective media allowed the growth of copiothrophic and oligothrophic bacteria to be estimated. The influence of fungicide (PCNB) and N-fertilizer on the number of bacteria in each biofilm was also evaluated. The pollution of water with fertilizer (being used for plant irrigation) was demonstrated to reduce the efficiency of filtration more than fungicide addition (the amount of DNA from those investigated pathogens in the water decreased with time). The amount of bacteria in SSF biofilm readily increased after application of N-fertilizer in contrast to fungicide (PCNB) addition.

Summary Real-time PCR assays based on the TaqMan system and using ITS sequences were developed for the identification of Phytophthora species, including P. cactorum, P. megasperma, P. plurivora, P. pseudosyringae and P. quercina, all of which are currently causing significant damage to roots of forest trees in both managed stands and natural ecosystems. Total genomic DNA was extracted from mycelia of aforementioned Phytophthora isolates. Species-specific primers for P. cactorum, P. megasperma, P. plurivora, P. pseudosyringae and P. quercina were designed based on ITS sequences of rDNA. The amplification efficiency of target DNA varied from 93.1% (P. pseudosyringae) to 106.8% (P. quercina). The limit of the detection was calculated as 100 – 1,000 fg DNA, depending on the Phytophthora species. In mixed soil samples, all Phytophthora species were detected for Ct values shifted by 0.7 – 2.1 cycles. Based on these real-time PCR assays we were able to identify the five Phytophthora species. These techniques will be of value in the identification of these pathogens, which may cause up to 80 – 90% fine root loss in oak stands.

The article discusses the problem of teachers’ communicative competences and presents it from both the theoretical and empirical perspective. The first part of the article helps understand the communication process and defines teachers’ communicative styles at school and barriers for pedagogical communication. The second part presents the results of diagnostic research on selected teachers’ communicative competences. The research problems included: How do teachers understand the communication process at school, and what are the factors determining its level? What communicative styles do teachers use? What are the barriers in communication between teachers and students? The article concludes with remarks and postulates.

The European Fraxinus species are threatened by the alien invasive pathogen Hymenoscyphus fraxineus, which was introduced into Poland in the 1990s and has spread throughout the European continent, causing a large-scale decline of ash. There are no effective treatments to protect ash trees against ash dieback, which is caused by this pathogen, showing high variations in susceptibility at the individual level. Earlier studies have shown that the application of phosphites could improve the health of treated seedlings after artificial inoculation with H. fraxineus. Three-year-old F. excelsior seedlings were inoculated with the following pathogens: a H. fraxineus, Phytophthora species mixture (P. plurivora, P. megasperma, and P. taxon hungarica), in combination with two pathogens and mock-inoculated as the control, and then either watered or treated with ammonium phosphite (Actifos). Results showed significant differences in the survival of seedlings and symptoms of disease development among the treatments. Chlorophyll-a fluorescence parameters indicated a decrease in photosynthetic efficiency in infected plants, suggesting that they were under strong biotic stress, but none of the parameters could be used as a reliable bioindicator for ash decline disease. The application of Actifos enhanced the production of triterpenes (ursolic and oleanolic acid), and decreased the production of phenols (tyrosol) and sterols (&beta, sitosterol) in seedlings infected with H. fraxineus. Treatment with Actifos caused seedlings to enhance their response to pathogen(s) attack and increase their survival probability.