Leaf micromorphology of Aesculus hippocastanum L. and damage caused by leaf-mining larvae of Cameraria ohridella Deschka and Dimić

The present study is a continuation of our research on the structure of healthy leaves of Aesculus hippocastanum and leaves damaged by larvae of Cameraria ohridella. In this study, the epidermal micromorphology of both leaf surfaces in A. hippocastanum was investigated by scanning electron microscopy (SEM). Light microscopy was used to examine on which side of the leaf blades eggs of Cameraria ohridella were laid. The characteristic features of the adaxial and abaxial epidermis were shown. In the hypostomatic leaves of the studied species, the stomata occurred at a density of 173 × mm-2  and they represented the cyclocytic type. A striated layer of the cuticle was observed only in the adaxial epidermis in which glandular hairs were also present along the midribs. Non-glandular trichomes grew only on the surface of the midribs or in their axils in the abaxial epidermis. We found eggs of C. ohridella only on the adaxial surface of the epidermis. Using SEM, we also observed in the mines leaf tissues damaged by C. ohridella. We found palisade parenchyma to be absent, whereas in the spongy parenchyma there could be seen large intercellular spaces and at places a dense mass of organic matter, formed from damaged cells and larval excrement. The vascular bundles and calcium oxalate crystals remained in the feeding places. We found numerous bacteria, fungal spores and hyphae as well as cleistothecia of Erysiphales in the mines on the surface of the damaged mesophyll. The glandular trichomes occurring only locally on the leaves, the relatively thin cell walls of the epidermis and a not well-developed cuticle layer on their surface do not protect sufficiently these leaves against the invasion of C. ohridella. On the other hand, damaged tissue areas are a convenient place for the growth of bacteria and fungi

An analysis of the content of pteridophyta spores in aeroplankton of Lublin (2013–2014)

Similarly to fungal spores and pollen grains, pteridophytic spores can cause allergies in humans. Pteridophyta spore concentrations in the air of Lublin, under the conditions of central-eastern Poland, were first studied over the period 2013–2014. The volumetric method was used in this study. The research showed that that spores of ferns belonging to the following genera: Asplenium, Athyrium, Blechnum, Botrychium, Cystopteris, Dryopteris, Matteuccia, Osmunda, Polypodium and Pteridium, occur in aeroplankton. Spores were recorded in low concentrations and they occurred in a dispersed pattern during the season. They were found to be absent on some days. Among the above-mentioned genera, Dryopteris and Athyrium showed the highest content of spores in aerosol. In both years of the study (2013 and 2014), similar annual spore counts were recorded, respectively 69 and 63. The most spores were identified in August

Betula pollen season in southern Poland in 2016

The paper presents a comparison of birch pollen seasons in 2016 in study sites located in the southern part of Poland: Zielona Gora, Opole, Wroclaw, Sosnowiec, Cracow, Lublin, and Guciow in the Roztocze National Park. The pollen concentrations were measured with the volumetric method using Burkard or Lanzoni pollen samplers. The annual pollen sum was calculated for each measurement site. In 2016, the birch pollen season started at a similar time, i.e. between 4th and 6th April in all the localities. The highest annual sums and maximum pollen concentrations were recorded in Lublin and Guciow. The maximum concentrations of birch pollen were noted from 5th and 15th April, with the highest value in Lublin, i.e. 8573 P/m3 (14.04)

Alternaria spores in the air of selected Polish cities in 2015

The aim of the study was to compare the concentration of Alternaria spores in the cities of Poznan, Bydgoszcz, Sosnowiec, Piotrkow Trybunalski, Olsztyn, Opole, Warsaw, Zielona Gora, Lublin and Szczecin in 2015. Measurements were performed by the volumetric method (Hirst). Alternaria season was defined as the period in which 90% of the annual total catch occurred. The Alternaria season started first in Bydgoszcz on the 27th May and in the other cities it started during the next four weeks. The highest airborne concentration of 900 Alternaria spores × m-3 was noted in Lublin on the 4th July

The origin of pine pollen grains captured from air at Calypsobyen, Svalbard

Spitsbergen is the largest island in the Svalbard Archipelago (Norway) that has been permanently populated. The harsh Arctic climate prevents development of large vascular plants such as trees. A two-year aerobiological survey was conducted within the framework of two consecutive polar expeditions (2014 and 2015) in Spitsbergen (Calypsobyen, Bellsund). The air quality was measured continuously from June/July to August using a 7-day volumetric air sampler, Tauber trap and moss specimens. Collected air samples and gravimetric pollen deposits were processed following transfer to sterile laboratory conditions and analyzed with the aid of light microscopy. Days when pine pollen grains were detected in the air were selected for further analysis. Clusters of back-trajectories, computed using the Hybrid Single Particle Lagrangian Integrated Trajectory model in combination with ArcGIS software as well as the Flextra trajectory model, showed the movement of air masses to the sampling location at Hornsund, and thus indicated the likely origin of pollen grains. The GlobCover 2009 and CORINE Land Cover 2012 datasets were employed to establish the distribution of coniferous forests in the areas of interest. Conclusions were drawn based on the analyses of the circulation of air masses, using visualization of global weather conditions forecast to supercomputers. For the first time we have demonstrated that pine pollen grains occurring in pine-free Spitsbergen, could originate from numerous locations, including Scandinavia, Iceland, Siberia and northern Canada. Pollen grains were transported via air masses for distances exceeding ~2000 km. Both air samples and gravimetric pollen deposits revealed the same pattern of Pinus pollen distribution

Changes in the pollen seasons of Acer spp. in Lublin, central-eastern Poland, in 2001–2015

Many plant species respond to the climate change reported in the recent decades, which is confirmed by the results of phenological and aerobiological investigations. This paper presents characteristics of the pollen seasons of Acer spp. revealed by aerobiological analyses performed with the volumetric method in Lublin, Poland in 2001–2015. Additionally, phenological observations of flowering of four Acer species, i.e., A. negundo, A. platanoides, A. campestre, and A. pseudoplatanus, were carried out in 2011–2012. The results indicate a slight upward trend in the annual totals of Acer pollen grains. Over the last 10 years, the annual totals of Acer pollen grains have increased in comparison to the previous 5-year period. Acceleration of the onset of pollen seasons and the dates of peak days was noted. The comparison of the pollen seasons and flowering phenology of four Acer species indicates that A. negundo and A. platanoides produce the highest concentrations of pollen grains, whereas the pollen of A. campestre and A. pseudoplatanus accounts for a significantly lower proportion of the pollen content in the air of Lublin