Piotr Łakomy

Lignin and lignans in plant defence: Insight from expression profiling of cinnamyl alcohol dehydrogenase genes during development and following fungal infection in Populus

Cinnamyl alcohol dehydrogenase (CAD) catalyses the final step in the biosynthesis of monolignol, the main component of lignin. Lignins, deposited in the secondary cell wall, play a role in plant defence against pathogens. We re-analysed the phylogeny of CAD/CAD-like genes using sequences from recently sequenced genomes, and analysed the temporal and spatial expression profiles of CAD/CAD-like genes in Populus trichocarpa healthy and infected plants. Three fungal pathogens (Rhizoctonia solani, Fusarium oxysporum, and Cytospora sp.), varying in lifestyle and pathogenicity, were used for plant infection. Phylogenetic analyses showed that CAD/CAD-like genes were distributed in classes represented by all members from angiosperm lineages including basal angiosperms and Selaginella. The analysed genes showed different expression profiles during development and demonstrated that three genes were involved in primary xylem maturation while five may function in secondary xylem formation. Expression analysis following inoculation with fungal pathogens, showed that five genes were induced in either stem or leaves. These results add further evidence that CAD/CAD-like genes have evolved specialised functions in plant development and defence against various pest and pathogens. Two genes (PoptrCAD11 and PoptrCAD15), which were induced under various stresses, could be treated as universal markers of plant defence using lignification or lignan biosynthesis.

Communities of fungi in decomposed wood of oak and pine

Abstract The abundance and diversity of wood decomposing fungi were investigated by isolating and cultivating filamentous fungi from wood and by detection of fruit bodies of ascomycetous and basidiomycetous fungi. The objective was to study the impact of forest management on fungi in 100-year-old oak and 87-year-old Scots pine forests in Northern Poland. Fungi were found on coarse woody debris of decayed stumps and fallen logs, boughs and branches in each of the three (managed and unmanaged) examined stands. In total, 226 species of Oomycota and fungi were recorded. Oak wood was colonized by one species of Oomycota and 141 species of fungi including Zygomycota (19 species), Ascomycota (103 species) and Basidiomycota (19 species). Scots pine wood was also colonized by one species of Oomycota and 138 species of fungi including Zygomycota (19 species), Ascomycota (90 species) and Basidiomycota (29 species). In the first, second and third stages of decomposition, the oak wood was colonized by 101, 89 and 56 species of fungi respectively and pine wood was colonized by 82, 103 and 47 species respectively. Eighty three of the observed species (37%) occurred on both types of wood, while the other species displayed nutritional preferences. A decrease in the number of species with advancing decay indicates the necessity for a continuous supply of dead wood to the forest ecosystem. This supply would secure the continuity of fauna and flora and guarantee a stable forest development. The nutritional and ecological preferences of many fungal species furthermore indicate the necessity of supplying the forests with wood of different species. In commercially managed forests the results obtained here will aid in: (i) the development of strategies for effective dead wood management in the context of forest productivity and future wood stock growth, as well as (ii) finding a compromise between forest management requirements and environmental protection.

Occurrence of Erysiphe alphitoides in oak stands affected by flood disaster

Abstract Pedunculate oak (Quercus robur L.) is the most valuable deciduous tree species in Poland. For almost 30 years, an oak decline resulting from stress factors leading to a decrease of tree vitality in the long-term has been observed. The aim of the present study was to determine the proportion of leaves infected by the fungus Erysiphe alphitoides, the cause of powdery mildew, in post-flood oak stands situated in the Forest District Wołów (51°32’N, 16°62’E) as well as to evaluate effects of powdery mildew with respect to the oak decline. In order to record the powdery mildew incidence, we selec ted three trees in each of the ten investigated oak stands, and 200 leaves were collected from the upper part of the crowns. The percentage of infected leaves as well as the reduction of carbon assimilation capacity was assessed. Furthermore, we evaluated the average reduction of carbon assimilation capacity and the percentage of withering branch tips in 25 adjacent trees. Incidences of powdery mildew were observed in seven out of the ten stands. The maximum tree damage did not exceed 22% leaf infection and mean defoliation within the study areas ranged from 18% to 61.4%. Non-withering branch tips were observed in one post-flood area as well as in one area situated outside the flooded region. Within the remaining areas studied, the average proportion of withering branch tips ranged from 0.4% to 13.8%. Statistical analyses showed that differences between the investigated stands with regard to the rate of powdery mildew occurrence were not significant. Correlating the means, however, revealed a relationship between powdery mildew incidence and branch tip withering. This relationship is a possible indication of the ongoing oak dieback. No statistically significant relationship between tree defoliation and powdery mildew incidence was found. The lack of statistical significance, as observed here, implies that water stagnation within the investigated stands had no effect on Erysiphe alphitoides infection.

Description of Heterobasidion annosum population occurring in Scots pine stands in Człopa Forest Districts II. Mycelium development in a dead wood

The aim of this study was to test the ability of dead wood colonization of Heterobasidion annosum isolates with known aggressiveness to the Scots pine seedlings. The experiment was established in Scots pine stand localized in the Człopa Forest District. Roots of six-month-old stumps were inoculated with mycelium of 19 genotypes of H. annosum Genotypes colonized wood of Scots pine roots on distance from 8.10 cm to 43.27 cm. The genotypes that colonized wood on a shortest distance and the most extensively differed significantly from others. The analysis of the ability of wood colonization by mycelium of genotypes in relations to its origin showed that genotypes collected from stumps overgrew the roots slightly stronger (about 14.5%) than those collected from trees, but differences were not significant. There were no differences between genotypes isolated from pines and beaches, either. Population of H. annosum differed in genotypes features conditioning the rate of its development in the environment and disease dynamics. Differentiation of these features of pathogen populations caused an unequal infection and disease development rate in stands. It seems that the most aggressive isolates colonize the stand fastest through root system.

Assessment of leaf damage in oak stands in the flood-affected Wołów Forest Division

Abstract This study examines the effect of flood on oak stands in the Wołów Forest Division by assessing the loss of leaf area due to insect feeding as determined in laboratory analyses of samples collected from standing trees. We compared stands, in which water stagnated for at least one month and stands with no water stagnation. It was found that the mean damage to the carbon assimilating organs of stands with stagnating water was lowered by approximately 6% compared to stands that were not affected by flood. Thus, no definite effect of flood contributing to losses of carbon assimilating organs in oak trees could be shown.

An attempt at valuation of wood from dead trees in Polish forests

This study suggests a method of valuation for wood coming from dead trees which was applied for pricing of such wood found in Polish forests. This study shows that in Polish forest there are approx. 52 million m3 biocenotic wood coming from dead or dying trees with an estimated value of 1.5 billion PLN/10 years.In 2007 and 2008 studies aimed to determine the effect of indoxacarb, substance classified as oxadiazines (Steward 30 WG) and beta-cyfluthrine, belonging to synthetic pyrethroids (Bulldock 025 EC), on the oxygen consumption rate by adult Anoplotrupes stercorosus were performed. Experiments were carried out under various ambient temperature conditions (14, 19, 24 i 29°C) using two ways of intoxication – contact intoxication, or by an ingestion of the biocide. In insects of control group an ambient temperature affected the oxygen consumption only to a small extent. Conversely – applying insecticides markedly potentiated the oxygen consumption, whereas it was also increasing together with an increase of the temperature. The way of the intoxication affected the oxygen consumption only to quite a small extent. However, its greatest changes were noted in animals treated by contact intoxication.The rising demand for energy and the need to acquire ever more energy quantities from renewable sources call for seeking energy sources in forestry. The analysis presents a simulation of wood quantities needed to meet the obligation to produce electricity from woody biomass. Three sources of energy were specified, which can be delivered to power plants: medium dimensional round firewood, small dimensional firewood and logging residues. The calculated quantity of wood required by the industrial energy sector will reach 15 million cu. meters. Forestry will be able to directly supply about 5.8 mill. cu. meters of wood for energy purposes, including 3.1 mill. cu. m of medium dimensional roundwood, 1.4 mill. cu. m of small dimensional wood and 1.35 mill. cu. m of woody material in the form of logging residues. The largest quantities of woody material will come from western and northern parts of the country. Taking into account the fact that considerable quantities of wood suitable for energy purposes are currently utilized for heating by rural communities, not much will be left for the industrial energy sector.The study was conducted on 13 areas in the Wołów Forest District in oak stands with the common oak as the dominant species. The stands in the Wołów Forest District located in the Odra valley, including the oak stands, were flooded in 1997 and 2010. The aim of this study was to analyse the influence of defoliation on radial growth of oaks in the post-flood stands. Recorded results showed an inferior growth in thickness and greater defoliation in the common oak in the post-flood stands. The average defoliation at 40% has a significant influence on radial growth. It seems advisable to include the capacity of radial growth in the assessment of the condition of trees.The effect of weather conditions on height increments of trees was investigated within eight age classes. Weather conditions (temperature and precipitation) were presented using Sielianinow’s hydrothermal index in the quarterly periods and the De Martonne index in the annual periods. Drought index in a given year was found to have a negative effect on height increments of trees in the following year. A significant effect of weather conditions found in a given increment year was observed only in the case of the youngest trees.

PRÓBA WYCENY WARTOŚCI DREWNA POCHODZĄCEGO Z MARTWYCH DRZEW W POLSKICH LASACH

This study suggests a method of valuation for wood coming from dead trees which was applied for pricing of such wood found in Polish forests. This study shows that in Polish forest there are approx. 52 million m3 biocenotic wood coming from dead or dying trees with an estimated value of 1.5 billion PLN/10 years.In 2007 and 2008 studies aimed to determine the effect of indoxacarb, substance classified as oxadiazines (Steward 30 WG) and beta-cyfluthrine, belonging to synthetic pyrethroids (Bulldock 025 EC), on the oxygen consumption rate by adult Anoplotrupes stercorosus were performed. Experiments were carried out under various ambient temperature conditions (14, 19, 24 i 29°C) using two ways of intoxication – contact intoxication, or by an ingestion of the biocide. In insects of control group an ambient temperature affected the oxygen consumption only to a small extent. Conversely – applying insecticides markedly potentiated the oxygen consumption, whereas it was also increasing together with an increase of the temperature. The way of the intoxication affected the oxygen consumption only to quite a small extent. However, its greatest changes were noted in animals treated by contact intoxication.The rising demand for energy and the need to acquire ever more energy quantities from renewable sources call for seeking energy sources in forestry. The analysis presents a simulation of wood quantities needed to meet the obligation to produce electricity from woody biomass. Three sources of energy were specified, which can be delivered to power plants: medium dimensional round firewood, small dimensional firewood and logging residues. The calculated quantity of wood required by the industrial energy sector will reach 15 million cu. meters. Forestry will be able to directly supply about 5.8 mill. cu. meters of wood for energy purposes, including 3.1 mill. cu. m of medium dimensional roundwood, 1.4 mill. cu. m of small dimensional wood and 1.35 mill. cu. m of woody material in the form of logging residues. The largest quantities of woody material will come from western and northern parts of the country. Taking into account the fact that considerable quantities of wood suitable for energy purposes are currently utilized for heating by rural communities, not much will be left for the industrial energy sector.The study was conducted on 13 areas in the Wołów Forest District in oak stands with the common oak as the dominant species. The stands in the Wołów Forest District located in the Odra valley, including the oak stands, were flooded in 1997 and 2010. The aim of this study was to analyse the influence of defoliation on radial growth of oaks in the post-flood stands. Recorded results showed an inferior growth in thickness and greater defoliation in the common oak in the post-flood stands. The average defoliation at 40% has a significant influence on radial growth. It seems advisable to include the capacity of radial growth in the assessment of the condition of trees.The effect of weather conditions on height increments of trees was investigated within eight age classes. Weather conditions (temperature and precipitation) were presented using Sielianinow’s hydrothermal index in the quarterly periods and the De Martonne index in the annual periods. Drought index in a given year was found to have a negative effect on height increments of trees in the following year. A significant effect of weather conditions found in a given increment year was observed only in the case of the youngest trees.