Tomasz Oszako and Justyna A. Nowakowska
Justyna A. Nowakowska, Anna Tereba and Tomasz Oszako
Justyna A. Nowakowska, Małgorzata Sułkowska and Tomasz Oszako
Anna Tereba, Agata Konecka and Justyna A. Nowakowska
The paper describes a number of molecular methods used in the past and now to analyze forest tree species. Taking into account the economic importance of forest trees and in view of the timber economy, wood properties and characteristics are essential factors subjected to control, observation and research. Molecular techniques that support traditional selection methods allow for genetic diversity analyses considering a range of research aspects. The development of these techniques at the turn of the last two decades has enabled wide-ranging use of molecular data in studies on forest tree populations. On the example of pine (Pinus L.), the paper presents data based on molecular studies as well as a variety of possibilities to apply the obtained results.
Anna Żółciak, Justyna Anna Nowakowska, Artur Pacia, Nenad Keča and Tomasz Oszako
Ash dieback caused by an alien, invasive fungus Hymenoscyphus fraxineus is a serious disease of European ash species in many parts in Europe. In Poland, the disease was recorded in the beginning of the 1990s. This study was performed in 2016–2017 with the aim to identify fungi isolated from ash shoots showing dieback symptoms in the Wolica Nature Reserve in Poland, as well as from shoots of two years-old ash seedlings inoculated with H. fraxineus in the greenhouse.
The most frequently isolated fungi from shoots of common ash (associated with the pathogenic fungus H. fraxineus) were identified on the basis of sequencing of the internal transcribed spacer region (ITS1) of fungal rDNA. In total, 19 fungal taxa were identified for ash shoots as follows: H. fraxineus, Fusarium avenaceum, Alternaria spp., Phomopsis oblonga, Diplodia mutila and other Phomopsis spp. The pathogen H. fraxineus was not found for all the shoots samples; one year after inoculation the aforementioned fungi and other species as: Alternaria alternata, Bionectria ochroleuca, Epicoccum nigrum, F. acuminatum, F. avenaceum, and Paraphaesphaeria neglecta were identified in inoculation point, as well as H. fraxineus. The same quantitative and qualitative changes of organisms were observed in the case of artificially colonised ash seedlings in the greenhouse, as well as in the shoots of adult ash trees in the forest.
Adam Okorski, Tomasz Oszako, Justyna A. Nowakowska and Agnieszka Pszczółkowska
Achieving high quality propagative material is difficult today due to the limited number of pesticides recommended for use. Simultaneously, EU regulations on Integrated Pest Management (IPM) in forest nurseries came into a force, requiring a search for alternative plant protection methods that are safe for humans, animals and the environment. In this paper, we present the possibilities of using bio-fungicides against diseases in forest nurseries, their mechanisms of action, as well as the direction of their development (according to IPM rules). We reviewed the results achieved by different research teams presenting the possibilities and trends in combatting Oomycetes and Fusarium spp. pathogens currently having the most important economic impact.
Adam Okorski, Agnieszka Pszczółkowska, Tomasz Oszako and Justyna A. Nowakowska
The possibility of using chemicals in European forestry is extremely limited due to the binding legal regulations and specific conditions concerning the market of plant protection products. This is reflected in the limited availability of active fungicides in forestry. Due to this limitation, practitioners using fungicides in forest nurseries and forest cultivation must have substantial knowledge of the biology of pathogens to ensure satisfactorily effective protection.
The work presented here provides an overview of the currently recommended fungicides in Polish forestry as well as the mechanisms of interaction between the active substances and the pathogen, the plant and mycorrhizal fungi. The risk of fungicide resistance, which has been insufficiently explored in the context of forest pathogens, is also discussed in this paper.
Miłosz Tkaczyk, Justyna A. Nowakowska and Tomasz Oszako
In the circumstances of only a limited number of pesticides being approved for use in forest nurseries, it is necessary to also examine the efficacy of new products available on the European market that stimulate growth and improve resilience and vitality among seedlings and saplings, with a view to the application of these products forming part of an integrated programme of plant protection. This paper describes trials of the three commercially available fertilizer products Actifos, Zielony Busz and Effective Microorganisms (EM), as carried out in seven Polish nurseries in an attempt to promote the growth of shoots and root systems of seedlings and saplings. In 64% of cases of it being used, Actifos was shown to stimulate growth significantly beyond control levels in the shoots of oak, beech, pine, spruce and alder saplings as well as the roots of young alders and oaks.
Tomasz Oszako, Katarzyna Sikora, Lassaâd Belbahri and Justyna A. Nowakowska
In Poland, about 20% of forest nurseries use irrigation water coming from natural superficial reservoirs, presumed to be the first source of infection caused by harmful pathogens belonging to the Oomycota class, especially Phytophthora genus and Pythium genus. The forest nursery is the only place where forest managers can react before pathogens leave it with asymptomatic plants or soil attached to their roots. The aim of this research was detection and identification phytopathogens in water samples. In order to recognise genus Phytophthora or Pythium in water collected from 33 places in five different forest districts in Poland, two DNA-based approaches of identification were applied: (i) the TaqMan probes, and (ii) sequencing of the ITS6/4 region.
The genomic DNA was obtained from 17 of 33 investigated water samples. TaqMan probes helped to identify 8 oomycetes present in 17 water samples. Based on ITS rDNA sequencing data, pathogens were identified in 17 cases, and this to the genus level (6 cases) and to the species level (11 cases). In total five Oomycetes species were identified, i.e. 3 Pythium species (Py. citrinum, Py. angustatum, Py. helicoides) and two Phytophthora species (P. lacustris sp. nov. - former taxon Salixsoil, P. gallica sp. nov.).
Tomasz Oszako, Katarzyna Sikora, Lassaâd Belbahri and Justyna A. Nowakowska
Pathogens of Phytophthora genus are common not only in forest nurseries and stands, but also in water courses. Species of Phytophthora spread with plants for plantings (and soil attached to them) and with water courses as well, attacking the plants growing in riparian ecosystems. Several specialized organisms damaging only one tree species were identified like P. alni on alders or P. quercina on oaks. Some Phytophthora species can develop on several hosts like P. plurivora and P. cactorum on oaks, beeches, alders, ashes and horse chestnuts. Other oomycetes like P. gallica species was found for the first time in Poland in water used for plant watering in forest nursery. Species P. lacustris and P. gonapodyides were found in superficial water. Phytophthora species P. polonica was identified in the declining alder stands for the first time in the world, and P. taxon hungarica and P. megasperma were found in the rhizosphere of seriously damaged ash stands for the first time in Poland. The most often isolated species were P. plurivora (clade 2) with frequency 37% and P. lacustris with frequency 33% (clade 6). The best represented clade 6 revealed the occurrence of 6 species: P. gonapodyides, P. lacustris, P. megasperma, P. sp. raspberry, P. taxon hungarica and P. taxon oak soil.