In the years 1998–2000 an investigation was carried out on ‘Jonagold’ apples harvested from 6-year old trees grafted on M.9, M.26, P 2, P 22 and P 60. In 1998 and 1999 the average calcium content in fruit was significantly higher than in 2000. The highest calcium was observed in the peel of apples, in each of the year. The effect of the rootstock on the level of calcium in the calyx, core and pedicle part of apples changed, depending on the vegetation season. In each year of the experiment the strongly dwarfing rootstock P 22 had the smallest share in the accumulation of calcium in the different parts of apples.

The paper presents the results of chemical analyses of different organs of ‘Jonica’ apple trees. The trees were dwarfed with: rootstocks (M.9 and P60), and additionally, with bark grafting (in normal and inverted position), microinterstocks (M.9, P22, M.27) and retardant (Paclobutrazol). Microinterstock is an additional way of dwarfing, where a ring of bark taken from dwarfing rootstock is grafted on the tree’s trunk. In the years 1996–1999 fruit, leaf, wood, bark and root samples of each treatment were collected. After washing, samples were dried, grounded and subjected to mineralization and analised for calcium by atomic absorption spectrophotometry. The highest concentration of Ca was noted in the bark of investigated trees (1.53% d.w.). Relatively high concentration of Ca was noted in leaves and roots (0.98% d.w. and 0.48% d.w. respectively). The lowest content was noted in wood and friuts (0.09% d.w. and 0.02% d.w.). Analised rootstocks did not affect significantly the leaves calcium content. On the contrary rootstocks influenced fruit Ca ammounts; the lower Ca content was noted in fruits from trees grafted on P60 rootstock. Bark graftage or microinterstocks did not influenced or lowered Ca fruit content. The only exception was microinterstock P22 which significantly increased fruit Ca ammounts. No correlation between leaf and fruit Ca content was found. Bark grafting and microinterstocks decreased root Ca content. This effect was especially evident in the first year after grafting.

Nitrogen (N) nutrition is a major means of controlling growth and fruiting of trees. In EU Countries, society’s expectations and political decisions have pushed for the adoption of sustainable ways to manage orchards. Guidelines for N management aim to limit fertiliser applications under threshold limits, in order to reduce N losses. Increasing the effectiveness of the recycling of the N present in the orchard is a basic step to reduce external N inputs. The availability of the stable isotope ¹⁵N as experimental tool has made possible significant advances in the knowledge of the fluxes of N at tree and orchard level. This paper discusses the N fluxes occurring within the tree both between the years and within the year (root-shoot-root N recycle) and their role in the vegetative and reproductive cycle of fruit trees.

The assessment of black cherry seedlings root system was carried out at the Didactic-Experimental Establishment of the UWM in Olsztyn in September 2002. The seeds from which the examined seedlings were obtained had been sown into the ground on 2 October 2001. The following seeds were used for the experiment: fresh, sown into the ground immediately after obtaining them from fruit, partly dried seeds and seed sown a month later than in the preceding case as well as physiologically immature seeds and whole fresh fruit. The root systems of seedlings obtained from seeds stored for 1 year and 2 years in open and closed “Twist” type jars at room temperature and in a freezer were also assessed. The largest proportions of seedlings were obtained from seeds stored for 1 year and 2 years in a freezer. The lowest proportions of seedlings were obtained from seeds sown a month later and from whole fresh fruit. In this experiment the most favorable development of the root system was observed in case of seedlings from seeds stored for 2 years in an open jar. The time from picking to sowing of seeds was of little importance. The seedlings from partly dried seeds and later sowing were characterized by the lowest mass of the root system.

The content of total iron, cuprum and boron in leaves of four chrysanthemum cultivars was studied in 12 growth cycles starting on the second day of each month throughout the year, from January to December. From the moment of potting, the plants were treated with a short day. In periods of naturally long days, the day was shortened to 10.5 hours using a black-out cover. No supplementary light was used. The time of culture associated with real insolation had a significant influence on micronutrients content. Maximum contents of cuprum and boron were recorded in the leaves of chrysanthemums grown in periods of light deficit. The reverse regularity in case of iron was observed.

Results of our experiments are interpreted according to fertilizing system developed by long-term experiments and investigations. The potassium fertilization and favourable N/K ratio can increase the frost tolerance of generative organs of fruit trees to some extent. The effect of suitable growing site can surpass the effect of fertilizers. Frequently, the increase of phosphorus and potassium levels in the soil and leaves are relatively small comparing to amount of fertilizers, because of the strong fixation in the fertilized soil layer and – in other cases – leaching from root zone. Main soil characters should be taken into consideration to determine the favourable phosphorus, potassium levels in the soil. The excess of lime can be compensated by potassium fertilization to some extent, but on acid soils the NPK fertilization may be more effective – or effective at all – following lime or dolomite application.

The six-year data of study of influence of soil application of biological and mineral fertilizers and their complex on the parameters of growth and cropping of apple variety Charavnitsa, budded on the semi-dwarfing 57-545 rootstock, were analyzed. It was found that application of biological fertilizers, the biological complex and the biological-mineral complex had a positive influence on parameters of growth of apple trees, the area of leaf plate and leaf area per tree as well as on mean fruit weight and fruit chemical composition. Application of mineral fertilizers had a negative effect on tree growth and yield. Application of various kinds of fertilizers did not affect the content or composition of pigments of leaves. Mineral fertilizers increased soil acidity and caused a slight increase of potassium, phosphorus and humus content. Application of biological products significantly lowered soil acidity to the optimum level for apple trees and considerably increased the contents of soil potassium, phosphorus and humus.

‘Katja’ apple trees on M.9 Emla, M.9 751, M.9 984 and P 60 were planted on a silty loam alluvial soil, strongly fixing K, in autumn 1992. They were grown on non-irrigated and irrigated plots, with different potassium fertilisation applied since 1980. Leaf samples were taken in the years 1999–2001. Irrigation had not any significant effect on leaf mineral element content. However, a tendency to increasing leaf K concentration and decreasing Mg concentration in irrigated trees was noted. Fertilisation, irrespective of the dose and mode of application, significantly affected leaf mineral status. The annual doses of 200 kg K₂O·ha^-1 and cumulative dose of 800 kg K₂O·ha^-1, applied once in every four years, significantly increased K and P concentration. Leaves of non-fertilised trees contained more Mg. Leaves of P 60 contained more Ca and less Mg.

A differentiated ability of heavy metals accumulation was found between different lettuce cultivars. In combinations with an addition of lead and cadmium grown in autumn, the least amount of lead was accumulated by Agora, Regina and Bona cvs, while the least amount of cadmium was found in Saba and Bona cvs. In spring, Syrena cv. accumulated the least amount of lead, while Marta cv. showed the least amount of cadmium.

Roots of radish (Raphanus sativus L. var. radicula Pers.) of Rowa cv. seedlings grown in water cultures (pH 4.3) have been tested. Aluminum as AlCl₃·6H₂O has been applied at 0, 10, 20 and 40 mg·dm^-3 concentrations. Inhibition of the growth of root elongation and the following changes of root morphology have been observed after aluminum treatment: browning and thickening, root cap elongation or falling off, bending of the apex root and cracks on its surface. Roots have been characterized with the change of hair length and lateral zones. First lateral roots occurred closer to the basal root apex than first hair. Reduction of hair length was noticed too. Atrophy of outer root tissues has been accompanied by great enlargement of cortex cells size as a result of their hypertrophy.

The object of the studies were saprophytic bacteria and fungi isolated from the soil after the cultivation of spring rye and common vetch. The studies were conducted in laboratory conditions. The antagonistic effect of the isolates of Bacillus spp., Pseudomonas spp., Trichoderma hamatum and Trichoderma koningii was determined towards such pathogenic fungi as Alternaria alternata., Botrytis cinerea, Fusarium culmorum, Fusarium oxysporum, Fusarium solani, Phoma exigua var exigua, Pythium irregulare, Rhizoctonia solani and Sclerotinia sclerotiorum. It turned out on the basis of the obtained results that the highest antagonistic effect was characteristic of the isolates of Trichoderma koningii, while the smallest of Trichoderma hamatum. Among the examined bacteria isolates Pseudomonas spp. appeared to be a poorer antagonist than Bacillus spp.

The experiment was conducted at Fruit Experimental Station Samotwór near Wroclaw in the years 1998–2003, The aim of the experiment was to estimate the influence of six rootstocks on the growth, cropping and fruit quality of some new scab-resistant apple cultivars. Two of the cultivars were Polish –Waleria and Sawa, and four of them were Czech – ‘Rosana’, ‘Rubinola’, ‘Rajka’ and ‘Topaz’. In the spring of 1998 maiden trees on rootstocks M.9, P2, P60, P16, P22 and M.27 were planted at the spacing 3.5×1.2 m (2380 trees/ha). The results of six-year-long studies confirmed that ‘Rubinola’ and ‘Rajka’ were characterised by the strongest vigour (the lowest crop efficiency indices – CEI), while ‘Rosana’ grew very weakly (the highest CEI). Fruit quality in terms of presentation and taste was the best in the case of ‘Rubinola’. ‘Sawa’, ‘Rubinola’ and ‘Topaz’ had the biggest potential for commercial production. The rootstocks M.9 and P60 proved to be the most useful for the studied apple cultivars.

The experiment was established at Felin Experimental Farm of Lublin Agricultural University. The aim of this study was to estimate the growth and the branched of the six stocks used in the production of the cherry and the sweet cherry young trees. Results of the study proved that F 12/1 and Colt stocks were the most vigorous, while P-HL 6 and P-HL 84 were characterised by the weakest growth. The best branched was by mahaleb cherry seedlings and P-HL 84 stock. The greatest precentage of cut off the buds of the cherry cv. ‘Łutówka’ proved on the rootstocks: F 12/1, P-HL 84 and P-HL 6.

In 2001–2003 on Sandomierska Upland researches were done in order to estimate the influence of the rootstock and the age on the growth and yielding of the ‘Szampion’ trees. This cultivar was grafted on P60 and M.26 rootstock. It was stated that the ‘Szampion’ had given abundant crops (73–113 t/ha on average) due to magnificent conditions of Sandomierska Upland. The height of the yield depended in a significant way on the rootstock (six-year-old trees on P60 yielded considerably better than on M.26) and the age of trees – the trees on M.26 younger by 2 years provided a significantly better yield. The growth and quality of fruits of the ‘Szampion’ depended on the age of scrutinized trees. The proportion of fruit with the diameter of more than 7.0 cm in all the studied combinations exceeded 80% and it was the highest in the trees on P60.

The purpose of this paper was to determine the sunflower (Helianthus annuus L.) reaction to nickel depending on the metal concentration and penetration way, i.e. through roots or leaves. Nickel was introduced into the nutritional solution (intraroot application) at amounts: 0 (control), 35, 100 or 200 µM, while intraleaf application was performed by spraying plants with water (control) or nickel containing solution at the concentration of 5 or 10 µM. Plants treated with nickel intraroot than intraleaf were characterized by a considerably higher metal content in roots and lower in leaves. Independently of the penetration way increasing metal concentrations caused a significant decrease of the parameters of physiological root activity, i.e. the root volume, total and active adsorption surface and 1 cm³ root active surface, in that a greater decrease of the root parameters was shown on intraroot than intraleaf application of the metal. Environment contamination with nickel caused also a chlorophyll concentration decrease in leaves, in that intraleaf nickel application, in contrast to intraroot, resulted in a higher decrease of chlorophyll b than a. Older than younger leaves showed a higher susceptibility to nickel applied intraroot, whereas roots were resistant to nickel applied intraleaf. The content of S-SO₄ in the sunflower depended on the nickel concentration and penetration way – intraleaf nickel application caused significant S-SO₄ increase in leaves and roots, whereas intraroot application resulted in S-SO₄ content increase especially in roots.

The influence of the addition of Potassium Ekosorb to black soil and sandy soil on water content in soils, gas exchange in leaves and yielding of strawberry plants cultivar Senga Sengana, Dukat, Kent and Elsanta was estimated in a field experiment. The obtained results show that the addition of hydrogel increased content of water in both types of soil; however, the effect was on average twice higher in black soil than in sandy soil. The highest stomatal conductance of leaves, photosynthesis and transpiration were observed in plants cultivated in both black and sandy soil with the addition of 3 g dm^-3 of hydrogel. The addition of higher dose influenced in an ambiguous way on the values of analyzed features of leaves. Yet, regardless of the applied dose of Ekosorb, the stomatal conductance, transpiration and photosynthesis of plants cultivated in black soil were 1.8–2.9 times higher than in sandy soil. The highest yields of fruit on both types of soil were obtained from plants which took advantage of presence of 3 g dm^-3 of hydrogel. The application of 6 g dm^-3 influenced on decreasing of plant yields. The weakest reaction on both types of soil occurred in strawberry cultivar Elsanta.

The study was carried out on two highbush blueberry cultivars: Bluecrop and Darrow in 2001 and 2002 seasons. Analyses for phytochemical contents in berries were made during commercial maturity of fruit. Concentration of anthocyanins and low molecular weight thiol compounds was significantly higher in ´Darrow´ berries in comparison to Bluecrop cv., irrespective of the harvest year. Tested cultivars did not differ in the ratio of the reduced form of glutathione in its total quantity. As opposed to this, the higher proportion of the reduced form of ascorbate in its total concentration was noted for ´Bluecrop´, but it was statistically proven only in the first year of research. A very low activity of antioxidative enzymes was noted, however on the average, considerably higher activity of glutathione reductase showed ´Darrow´, whereas ´Bluecrop´ had higher catalase activity. The ascorbate peroxidase activity was not detected in the extracts of ´Bluecrop´s’ berries. Berries of ´Darrow´, which exhibited, in general, the higher antioxidants content in the first year of the study, were harvested at two different dates in 2002: in the middle of July and at the end of August. The harvest date had a significant effect on the level of some phytochemicals. The fruit harvested in August had lower content of cysteine, glutathione, phenolics, flavonols and anthocyanins than the ones harvested in July. Ascorbate content was similar at both harvest dates. Growing season also had the influence on antioxidant properties, especially on the content of ascorbic acid.