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.

Due to climate changes, drought- and lime-tolerant Prunus mahaleb rootstock may gain importance. Among the Mahaleb rootstocks and hybrids, there are standard and moderate-vigorous types, but their intensive testing in orchards is still needed. Our paper reports on testing rootstocks SL 64, Bogdány, Magyar, SM 11/4 clonal Mahalebs, and the hybrid MaxMa 14. ‘Carmen’, ‘Vera’, ‘Paulus’, and ‘Rita’ sweet cherry trees were trained on the above rootstocks to the principles of Hungarian Cherry Spindle at a spacing of 1.6 × 5 m. Rootstocks SL 64, Bogdány, and SM 11/4 proved to be vigorous, while on rootstocks Magyar and MaxMa 14, the trees were moderately vigorous, about 80%. ‘Carmen’, ‘Vera’, and ‘Rita’ on Magyar and MaxMa 14 produced high cumulative yields without significant differences, while ‘Paulus’ trees were most productive on Bogdány rootstock. ‘Carmen’ on Bogdány rootstock, ‘Vera’ on Magyar and Maxma 14 rootstock, and ‘Rita’ on MaxMa 14 were more precocious than on SL 64. Contrary to SL 64 and MaxMa 14, both Magyar and Bogdány rootstocks resulted in abundant flat branching and good fruit size. Our conclusion is that trees on Magyar and Bogdány rootstocks fit well to the Hungarian Cherry Spindle orchard system with 1250 tree/ha orchard density.

In the last five decades, the use of rootstocks and scions has changed, along with their systems of cultivation. Associated with climate change, fruit trees face new ecological and phytopathological challenges. Rootstocks affect the generative and vegetative performance of a scion, such as productivity, span of nonbearing period, growth vigor, shelf-life and quality of fruits. According to a recent study, they also affect the frost tolerance of floral buds. Several traits of rootstocks facilitate the growth of a grafted tree under different climatic and soil conditions. Due to the high risks of cultivation, it is extremely important to determine which rootstocks are suitable for successful apricot production. Origin, effects on vegetative and generative traits, tolerance, resistance and adaptability of rootstocks are summarized in this review to select suitable rootstock for apricot cultivars under Hungarian conditions.

In contrast to other European countries, the nurseries in Hungary mainly use Myrobalan seedlings as rootstock for plum trees; no experience with other rootstocks is available yet. The aim of our research was to gather experience and recommend rootstocks to growers that are adapted to the climatic conditions and can be used in high-density intensive orchards. In the experiment, six rootstocks (Myrobalan seedlings, ‘St. Julien GF655/2’, ‘St. Julien A’, ‘Fereley’, ‘Wangenheim’ and ‘WaVit’) and five varieties (‘Topper’, ‘Toptaste’, ‘Topfive’, ‘Čačanska lepotica’ and ‘Jojo’) were tested. The experimental plantation was established in Kecskemét, in the lowland region of Hungary, which is characterised by low humus content and dry climatic conditions. The trees received two different irrigation doses from 2012 onwards, one for each half of the trees (six trees) of a combination. The first irrigation dose was 2 L and the second was 4 L per hour. Trees with the highest trunk cross-sectional area (TCSA) and canopy volume were ‘Topper’, ‘Toptaste’ and ‘Topfive’ on the ‘Fereley’ rootstock, but this rootstock showed lower survival, with only 33–50% of trees surviving the 2× dose irrigation. The average TCSA values of the rootstocks showed that ‘Wangenheim’ and ‘WaVit’ rootstocks resulted in too poor growth. In contrast, the Myrobalan seedling (Sdlg) and ‘St. Julien GF655/2’ provided strong growth to the trees based on the TCSA and canopy volume data. The results of the analysis of shoot growth showed that irrigation did not significantly affect shoot length, except for ‘Jojo’. The plum trees developed fruit trees typical of the cultivars after fruiting, with little influence of the rootstocks. ‘Topper’ and ‘Čačanska lepotica’ were dominated by bunched and bunched shoots, while ‘Topfive’ was dominated by short shoots and ‘Toptaste’ developed the highest proportion of long shoots.