Search

• Aesculus hippocastanum is a valuable ornamental tree present in urban greenery. • Defense strategies of Aesculus leaves against Cameraria ohridella were studied. • Increased polyphenol content was observed in infested Aesculus hippocastanum leaves. • New details of the morphology and behaviour of C. ohridella larvae were provided. • Histochemical tests, fluorescence assays, and scanning electron microscopy were used. Although Cameraria ohridella is a pest mining Aesculus hippocastanum leaves, has been known in Europe for 30 years, there is still no completely efficient method for control of this insect. The defence strategies of A. hippocastanum leaves against infestations by this pest have not been fully elucidated yet. The aim of the present study was to identify the defence strategy adopted by A. hippocastanum against the pest based on anatomical and histochemical analyses of leaves as well as to provide details of the morphology and behaviour of the developmental forms of C. ohridella. The study was carried out using a scanning, light, and fluorescence microscope. It was demonstrated that the response of the A. hippocastanum to C. ohridella larval infestations consisted in enhanced accumulation of phenolic compounds in tissues located at the border of mines and in the thickened layer of the leaf supporting the cocoon. Thorough analyses of the consecutive developmental stages of C. ohridella revealed new previously unknown features of larva L 1 and some details of the mandible structures of feeding larvae L 1 -L 4 and the characteristics of the cocoon structure, which is produced by larvae L 5 and L 6. We have found six stages in the developmental cycle of this pest in the present study. [ABSTRACT FROM AUTHOR]

• Tilia pollen can cause pollen allergy in sensitive people. • In Poland, the risk of allergy to Tilia pollen occurs in June, July, and also in May. • The highest counts of Tilia pollen occur during the T. cordata flowering period. • The acceleration in the pollen season onset was almost 14 days during 18 years. • In 2018, the annual pollen sum increased by more than three times. Lindens belong to valued trees that are frequently planted in urban green areas. Nevertheless, during their flowering they can pose a risk to sensitive people in cities due to their allergenic pollen. This paper presents the results of a 3-year phenological study (2016–2018) and an 18-year aerobiological study (2001–2018) conducted in Lublin (Poland). The flowering phenology data for the following five species: T. americana , T. cordata , T. × euchlora , T. platyphyllos , and T. tomentosa , were compared with the data regarding Tilia pollen seasons. It was shown that the largest amounts of airborne Tilia pollen grains occur during the full flowering period of T. cordata and that the flowering sequence of the linden species studied is constant during the growing season: T. platyphyllos , T. americana , T. cordata , T. × euchlora , and T. tomentosa. We found pollen seasons to start earlier by 14 days and to be extended by 15 days. Throughout the study period, the annual Tilia pollen sum did not change significantly. However, in 2018 in which there was a significant increase in temperature above the average for the previous 17 years, flowering and pollen release distinctly accelerated, and the annual pollen sum increased more than three times compared to the average for the previous 17 years. In central-eastern Poland, the risk of pollen allergy due to the presence of Tilia pollen occurs in May, June, and July. We recorded the highest linden pollen concentrations in June. Due to the acceleration of flowering and pollen release in linden trees as a result of global warming, the incidence of pollen allergy in central Europe can be expected to become more intense already in the second half of May. Therefore, linden plantings in new urban green areas should be planned to be established at some distance from residential estates. [ABSTRACT FROM AUTHOR]

The dataset presents a 43 year-long reanalysis of pollen seasons for three major allergenic genera of trees in Europe: alder (Alnus), birch (Betula), and olive (Olea). Driven by the meteorological reanalysis ERA5, the atmospheric composition model SILAM predicted the flowering period and calculated the Europe-wide dispersion pattern of pollen for the years 1980-2022. The model applied an extended 4-dimensional variational data assimilation of in-situ observations of aerobiological networks in 34 European countries to reproduce the inter-annual variability and trends of pollen production and distribution. The control variable of the assimilation procedure was the total pollen release during each flowering season, implemented as an annual correction factor to the mean pollen production. The dataset was designed as an input to studies on climate-induced and anthropogenically driven changes in the European vegetation, biodiversity monitoring, bioaerosol modelling and assessment, as well as, in combination with intra-seasonal observations, for health-related applications., (© 2024. The Author(s).)

In recent years, allergies due to airborne pollen allergens have shown an increasing trend, along with the severity of allergic symptoms in most industrialized countries, while synergism with other common atmospheric pollutants has also been identified as affecting the overall quality of citizenly life. In this study, we propose the state-of-the-art WRF-Chem model, which is a complex Eulerian meteorological model integrated on-line with atmospheric chemistry. We used a combination of the WRF-Chem extended towards birch pollen, and the emission module based on heating degree days, which has not been tested before. The simulations were run for the moderate season in terms of birch pollen concentrations (year 2015) and high season (year 2016) over Central Europe, which were validated against 11 observational stations located in Poland. The results show that there is a big difference in the model's performance for the two modelled years. In general, the model overestimates birch pollen concentrations for the moderate season and highly underestimates birch pollen concentrations for the year 2016. The model was able to predict birch pollen concentrations for first allergy symptoms (above 20 pollen m -3 ) as well as for severe symptoms (above 90 pollen m -3 ) with probability of detection at 0.78 and 0.68 and success ratio at 0.75 and 0.57, respectively for the year 2015. However, the model failed to reproduce these parameters for the year 2016. The results indicate the potential role of correcting the total seasonal pollen emission in improving the model's performance, especially for specific years in terms of pollen productivity. The application of chemical transport models such as WRF-Chem for pollen modelling provides a great opportunity for simultaneous simulations of chemical air pollution and allergic pollen with one goal, which is a step forward for studying and understanding the co-exposure of these particles in the air.