This work considers dust deposition and the heavy metal (HM) content on leaves of urban trees (Acer platanoides L. ‘Globosum,’ Fraxinus excelsior L. ‘Westhof’s Glorie’ and Tilia tomentosa Moench.) in order to estimate the trees’ capacity to remove dust and HM from the air. Leaves were collected from the Buda Arboretum and from different streets of heavy traffic in Budapest, Hungary, during 2015 and 2016. At each site, five trees were sampled by collecting 6 leaves from each tree from the height of 2–3 m. Dust deposits on the leaves were removed by soaking the fresh foliage in distilled water for 20 h and then washed with ultrasound shaking. Afterward, the leaves were dried to constant weight and then they were digested in nitric acid–hydrogen peroxide treatment, and their Pb, Fe, Ni, Zn and Cu contents were measured using an inductively coupled plasma (ICP AS) spectrometer. The removed dust deposit was dried, and after a similar digestion treatment the Pb, Fe, Ni, Zn and Cu contents were measured using an AURORA AI 1200 AAS appliance. The HM deposit was calculated in mg m–2 leaf surface area. In 2015, the amount of foliar dust deposit from spring to autumn increased from 86.3 to 270.2 mg m–2. The most efficient tree species in trapping dust on their leaves was the silver linden (98.5–123.5 mg m−2), followed by the Norway maple (74.2–84.8 mg m−2) and the common ash (62.8–74.6 mg m−2). The deposit of HM elements showed seasonal differences: the quantity of Fe and Pb deposit on autumnal leaves increased five- to tenfold, while other heavy metals did not show accumulation. Silver linden with its pubescent (hairy) leaf surface proved to be most efficient in entrapping and retaining dust and heavy metals. The 60–100% higher Pb and Fe content of autumnal leaves indicate that over the season leaves may absorb Fe and Pb from the foliar dust. Our results confirmed that the foliar dust is a potential indicator for monitoring the HM content in the air. We also show that foliar dust deposits should be considered when estimating the capacity of urban trees to clean the air.

In this study the 5-amino-levulic acid containing Pentakeep-V nano-fertilizer was examined in 0.3 ml/l, 0.5 ml/l and 0.7 ml/l concentrations with irrigating or spraying treatment on Begonia x tuberhybrida 'Nonstop' seedling production. The experiment was conducted in Zajzon, in a 300 m 2 heated plastic tunnel, from January 2012 to June 2012. Best result was obtained with 0.5 ml/l concentration in the case of all examined parameters. Pentakeep-V had positive effect in all examined concentrations with both ways of treatments on all measured parameters instead of plant height. The plant growing time was shortened thanking to the treatments. Using additional artificial light plants developed more and bigger flowers. Spraying was more effective comparing to irrigation. All the treatments had positive effect on chlorophyll content in the leaves. Summarizing Pentakeep-V nano-fertilizer can be offered in 0.5 ml/l concentration with spraying treatment in the seedling production of Begonia x tuberhybrida 'Nonstop'. Additional light enhances the effect in most examined parameters that is needed in the general practice during short day growing period.

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The segetal plant species that were present in the flora of the European area before the discovery of America are called archeophytes. We usually do not have accurate data on their place of origin and the method of spread, but their migration is attached to human activity in all cases [30]. Most botanists classify these species as native plants rather than calling adventive [35]. Their number is generally small, with 186 taxa in the Hungarian preliminary list, which we can surely say are archaeophytes. 88% of them are annual species, which originally found in field cereals [33]. .

In recent work the effect of 5-aminolevulinic-acid (ALA) agent (commercial name Pentakeep-V) was examined on the chlorophyll content, growth and development of Saintpaulia ionantha. The newly re-rooted potted plants were irrigated or sprayed with 0.3‰ or 0.5‰ Pentakeep-V solution, and plus 30% long lasting fertilizer was added to half of the all treatments. Control plants were sprayed with tap water. Best result were obtained on the field of flowering. All the treatments promoted chlorophyll-content in the leaves especially spraying with 0.3‰concentration. Plants treated with Pentakeep-V in both concentrations and independently from the spraying or irrigation flowered more than two weeks earlier than control and those that got plus 30% fertilizer. Besides in the case of some treatments the diameter of leaf rosette, the number and surface size of leaves grew comparing to the control. The longlasting fertilizer had positive effect on the fresh weight but none of treatments had effect on the dry weight.