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In the situation of limited number of pesticides being approved for use in forest nurseries it is necessary to examine new products available on European market that stimulate growth and improve resilience and vitality of seedlings as a part of intgrated plant protection program. Paper presents test of fertilizer Actifos used in seven Polish nurseries in order to stimulate the growth of seedlings. In 64% of cases, Actifos stimulated increament of shoots (significantly for oaks, beeches, pines, spruces and alders) as well as for roots (significantly only for alders and oaks)
The dynamic recent development of technologies provides more and more new tools, thanks to which it is possible to quickly detect and identify the chemical composition of volatile organic compounds of fungal origin. An ‘electronic nose’ (e−nose) is one of such tools. The Forest Research Institute launched in the period of 2018−2020 the project entitled ‘Forecasting threats to forest ecosystems through the implementation of innovative electronic odor recognition system’. Its aim is to use an electronic nose to detect the odors of fungal pathogens that cause damping−off of seedlings belonging to Fusarium, Rhizoctonia, Cylindrocarpon, Phytophthora and Pythium genera as well as pine foils on an example of pine tree lappet caterpillars (Dendrolimus pini L.). In presented paper special attention was paid to the organic compounds of fungal origin. Many authors indicate that a large number of fungi secrete specific organic compounds that can be used to recognize them. The composition of these compounds may, however, differ depending on the conditions in which the organism develops or even on the virulence itself. Similar research made it possible to introduce an e−nose device for general use. They are used, inter alia, at airports to detect dangerous substances, to determine the quality of coffee, or to check food for its suitability for consumption. The aim of this work is to review the basic information on the volatile organic compounds released by fungi, their composition and the possibility of using an electronic nose for their early detection. Paper provides information on: methods used to identify volatile organic compounds, the basic differences between the discussed methods and information on the examples of the use of this technology in various industries, from the food industry, through medicine, to the army.
In accordance with the National Program for Increasing Forest Cover it is planned to augment Poland’s forest cover to 30% by 2020. This task involves afforestation of agricultural lands by pioneer species that have low habitat requirements, such as the silver birch or the Scots pine. Application of sawdust, clear cutting residues, compost bark and compost beneath tree roots contributed to better development of the assimilation apparatus. The use of mineral fertilizer stimulated tree growth as well as improved physical and chemical properties of soil.
The study on the structure of Norway spruce old−growth stands of original provenience in upper mountain zone was carried out in a nature reserve ‘Śnieżnik Kłodzki', located in the Lądek Zdrój Forest District (SW Poland). The fieldwork was conducted in three spruce stands located at the altitude of 1,215 and 1,235 m a.s.l. The breast height diameters (dbh) of living trees were characterized. The aim of this study is to characterize the structure of dbh of trees in spruce stands of subalpine forest. Implementation of the objective will be associated with the characteristics of empirical distributions dbh and an indication of theoretical distributions of continuous random variable best approximating the structure of dbh. The comparison of empirical dbh distributions with 36 theoretical distributions were carried out, but goodness−of−fit tests proven statistically significant compatibility with seventeen of them: beta (4−parameter), Cauchy, exponential power, folded normal, gamma (3−parameter), generalized logistic, Laplace, logistic, loglogistic, loglogistic (3−parameter), lognormal (3−parameter), noncentral chi−square, normal, smallest extreme value, triangular, Weibull and Weibull (3−parameter). The dbh distributions in upper mountain spruce stands are the best fitted with logistic distribution, and subsequently loglogistic (3−parameter), generalized logistic and Weibull (3−parameter) distributions. That four distributions can be used in individual tree growth models while generating structure dbh of trees in the stand. The knowledge of dbh structure in protected stands could be helpful in shaping spruce stand structure in planned silvicultural treatments, and shows the need for silvicultural treatments in upper mountain spruce stands.
Root−feeding insects are an increasingly studied group of herbivores, whose impact on plant productivity and are some of the most damaging forest pests in Europe. Due to the mass feeding on the roots of seedlings and older trees in young plantation and stands, Melolonthinae larvae are classified as pests, which are the most dangerous on the land dedicated to afforestation. The research was located in the Wyszków Forest District (52°43‵15‵‵N; 21°39‵03‵‵E) on the mixed coniferous and mixed deciduous forest habitats. This study evaluated sawdust traps as the method for assessing abundance of Melolonthinae larvae in Scots pine plantations established artificially from open nursery, container production, and from natural regeneration. In spring 2015 i) ‘small sawdust pits’ in rows between seedlings, and ii) pits without soil in adjacent inter−rows as control were prepared. In spring and autumn 2016, and in spring 2017 sawdust and soil from both variants of pits were sieved and Melolonthinae larvae were counted and compared. The obtained results were analyzed in two ways. The first analysis compared the occurrence of grubs in small pits with or without sawdust, while the other one analysed influence of the time of making small pits, independently for the variant with or without sawdust. The final stage was to compare the number of Melolonthinae larvae in small pits between the origin of the seedlings. We found a greater number of grubs in spring assessment than in autumn. Both kinds of small pits showed higher number of Melolonthinae larvae when compared to traditional method of ‘great pits’. The number of Melolonthinae larvae was significantly higher on the plots with container seedlings than the others. The conceptual assumptions of this alternative and environmentally safe method of ‘sawdust traps’ seems to be optimistic.
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