The influence of chosen saccharides on the growth and development of the in vitro shoot cultures of Paulownia tomentosa – valuable and multi-purpose tree species. The mainly sucrose (10–50 g dm^-3), glucose and fructose (15.8 and 30 g dm^-3) were tested in three subsequent passages. Then the usefulness of saccharides in different applications of in vitro cultures was assessed. The basic MS medium supplemented with BA (1 mg dm^-3), NAA (0.1 mg dm^-3), and GA₃ (0.1 mg dm^-3) was used. Saccharides in tested concentrations influenced development of in vitro cultures. Proliferation of axillary shoots remained comparable whereas the development of adventitious shoots significantly and the frequency of vitrification decreased while the concentration of sucrose increased from 20 to 40 g dm^-3. Glucose (15.8 g dm^-3) stimulated both proliferation and elongation of axillary shoots. Sucrose (10 g dm^-3), and fructose (15.8 g dm^-3) favoured development of adventitious shoots and vitrification of cultures. The media supplemented with sucrose (30–40 g dm^-3) or glucose (15.8 g dm^-3) may be recommended for micropropagation of true-to-type plants, whereas sucrose (50 g dm^-3), and fructose (15.8 g dm^-3) for long term storage, and plant breeding, respectively.

In addition to flowers, cut foliage and leafy stems are very valuable florist material. However, florist greens frequently first loses its ornamental value in a flower arrangement, since it quickly wilts, fades, or browns. That is why it is important to develop agents for conditioning cut the florist greens that would extend its vase life effectively and inhibit senescence. Here we report on the effect of growth regulators and commercially available conditioning products on the post-harvest longevity of cut stems of Weigela florida 'Variegata Nana' and certain processes associated with their senescence. Senescence of W. florida cut stems resulted in reduced post-harvest quality, decrease in relative water content (RWC) and an increase in electrolyte leakage (E_L) in the leaf tissues. Chrysal Clear 2, applied in the form of a 24-hour pre-treatment, was the most effective in extending the longevity of cut stems of W. florida. The same conditioning product also had a beneficial effect on leaf tissue water content and the values of the chlorophyll fluorescence parameters, including maximum quantum yield and actual photochemical activity. Conditioning of W. florida stems in a solution of gibberellic acid at a concentration of 0.25 mg ∙ dm^-3 had the most beneficial effect on the cytoplasmatic membranes. However, the highest contentes of photosynthetic pigments (chlorophyll “a” and “b”), were found after the 24-hour pre-treatment of W. florida stems in a solution of 0.1 mmol ∙ dm^-3 benzyladenine and Chrysal Clear 2.

Non-chemical methods of agrophage control have gained increasing popularity recently, and particular attention has been paid to enhancing biodiversity in agrocenoses. Intercropping, i.e. growing of two or more crops (onions, carrots, dill, beans, Lacy phacelia, mustard) simultaneously in the same field, reduces pest infestations. The rationale behind intercropping is that different crops planted together act as attractants for beneficial insects (hoverflies, ladybirds) and effectively disorientate the pests (aphids, carrot flies) which are then unable to find host plants. This study was conducted in the Experimental Garden of the University of Warmia and Mazury in Olsztyn, in the growing seasons of 2009–2010. The experiment was established on brown soil of quality class IV b, and ridges were prepared in line with the generally observed standards of organic farming. The first experimental factor were six carrot cultivars differing with respect to the growth and development period: ‘Deep Purple F₁’, ‘Florida F₁’, ‘Interceptor F₁’, ‘Joba’, ‘Kazan F₁’ and ‘Purple Haze F₁’. The second experimental factor were three methods of carrot fly biocontrol, compared in the following treatments: control – unprotected plants, the application of the biocontrol agent Bioczos BR containing paraffin-coated garlic pulp (10 g cubes), carrots intercropped with dill cv. ‘Szmaragd’ and carrots intercropped with Welsh onions cv. ‘Parade’. Carrot-dill and carrot-Welsh onion intercropping effectively reduced damage to carrot roots caused by carrot fly larvae. The applied biological control methods had a significant effect on carrot yield. The application of Bioczos BR and carrot-Welsh onion intercropping had a beneficial influence on the total and marketable yield of carrot storage roots. Carrot-dill intercropping resulted in a significant yield decrease. The content of dry matter, total sugars and L-ascorbic acid in carrot roots was affected by the cultivar and the cultivar × biocontrol method interaction. Higher concentrations of dry matter and L-ascorbic acid were noted in carrot cultivars with purple-colored roots, ‘Deep Purple F₁’ and ‘Purple Haze F₁’. The average nitrate content of carrot storage roots did not exceed the maximum permissible levels set out in the Regulation of the Minister of Health.

Excessive amount of fruits on a tree results in loss of their weight. An advantageous way of improving the quality of e.g. plums is thinning their fruitlets. The experiment involving this problem was conducted in the years 2003–2005 at the Fruit Experimental Station in Samotwór near Wrocław. The subject of investigation were 10-year-old plum trees of two cultivars – ‘Valor’ and ‘President’, growing on a ‘Myrobalan’ rootstock (Prunus divaricata) in the spacing of 4 × 3 m (833 trees./ha). In the course of three subsequent years fruitlets were hand thinned one and two month after full blooming, as well as chemically treated, using the following preparations: Pomonit R-10 (NAA) + Ethrel (ethephon) and exclusively with Ethrel (14–10 days after trees blooming respectively). As a control there served trees which did not undergo fruitlets thinning. Hand thinning increased mean weight of ‘President’ fruits, while in ‘Valor’ cv. the same dependence was observed only when the treatment took place later. Chemical thinning did not significantly affect on fruit yield quality. In both plum cultivars, fruits obtained from not thinned trees characterized similar content of soluble solids and mineral components to those produced after application of hand and chemical thinning.

Common walnut, due to decorative habit of its crown, is a frequently growing tree in Lublin’s parks and gardens. Its presence in the town landscape provokes deeper analysis of the fauna occurring on it. The aim of this paper was to trace the changes in numerical force with reference to the weather conditions system, as well as to establish the bionomics of Panaphis juglandis (Goeze) occupying the trees of Juglans regia L. Studies were conducted on common walnut (Juglans regia L.) in Lublin in 2006–2008. Three locations were designed for observation: garden (A), park (B) and street-side (C). Numerical strength and bionomics of P. juglandis were determined. The greatest number of aphids was reported in the year 2007 in the park location. The course of weather conditions significantly affected the terms of spring and autumn presence of aphids. Warm spring with not very intense precipitation enhanced the development of P. juglandis. However, torrential rains and air temperatures exceeding 30ºC in summer limited the population dynamics of this aphid. In the developmental cycle the appearance of subsequent generations was observed from family founders through virginoparous females to sexual generation. Studies on female fecundity were performed. In all the study years the highest mean fecundity was that of the family founders, and the lowest was found in the females of sexual generation. The most fecunde virginoparous females (68.4 larvae · female^-1) were observed in spring 2006 in the street location. Observations were also undertaken, which concerned determining the place and term of aphid occurrence, as well as the number of eggs on lignified sprouts of Juglans regia L. The highest number of eggs was reported in 2008 in the park location.

Mulching has become increasingly common during recent decades not only in commercial horticulture. Mulching is especially important in organic farming. Crops are influenced by many factors when mulches are used. The field experiment was carried out in Aleksandras Stulginskis University (54º53'N, 23º50'E) in 2007–2009. The soil type – Calc(ar)i – Endohypogleyic Luvisol. Factor A – mulching: 1) without mulch; 2) straw; 3) peat; 4) sawdust; 5) grass. Factor B – thickness of mulch layer: 1) 5 cm; 2) 10 cm. The aim of this investigation was to evaluate the influence of organic mulches and different thickness of mulch layer on agrocenosis. The effect of grass mulch on vegetable agrocenosis was stronger compared with straw, peat and sawdust mulches. Mulching with 10 cm thickness of grass mulch layer had stronger effect compared with 5 cm thickness of grass mulch layer only at the 2^nd and 3^rd year of mulching. The condition of agrocenosis in plots without mulch declined and in plots mulched with 10 cm thickness of mulch layer improved.

One of the factors, determining early bearing of peach trees is planting them in high density. But it is difficult, because of the use of generative, strong growing rootstock. However the intensive growth of peach trees can be modified by planting in ridges and changing the shape of crown. The experiment was conducted in conditions of Lower Silesia Region. The experiment involved the assessment of trees on Manchurian peach rootstock, of ‘Suncrest’ and ‘Cresthaven’ cultivars, planted in the spring 2006, in: 3.5 × 1 m spacing (vertical axis) 3.75 × 2 m (spindel crown) and 4.25 × 3 m (open vase crown). Half of the trees following 3.5 × 1 m spacing were planted in a traditional way, while half of them, in ridges. The aim of research was determination of possibilities regarding the maintenance of the peach orchard on a seedling rootstock, with the use of a vertical axis crown form and the way of planting trees in ridges, as compared to trees planted traditionally and trained as spindle and an open vase crown. Summary yields from the first three years of yielding point to the possibility of obtaining high yield of peaches at dense trees planting in comparison to traditional model of peach orchard. The lowest yielding level characterized trees of both examined varieties planted in 4.25 × 3 m spacing and trained in the form of an open vase crown. The most intensive growth featured the trees trained in the form of an open vase crown and planted in 4.25 × 3 m spacing. Planting in ridges did not cause any significant diversity regarding peaches growth and yielding in high density of trees trained as vertical axis.

The UE-imposed restrictions on the manufacture and application of plant protection chemicals impose on the nurseryman the need to screen for new substances that are environmentally friendly and yet effective in the production of plant material. Biopreparations may constitute such a group as they contain substance little affecting the environment. The aim of the work was to evaluate effects of the biopreparation AlgaminoPlant on rooting of stem cuttings in Cornus alba ‘Aurea’ and C. alba ‘Elegantissima’. Freshly harvested cuttings were sprayed with the 0.2% water solution of the biopreparation. To compare its effectiveness with the commercial rooting powders used routinely in the nursery production part of the cuttings were treated with “Ukorzeniacz AB” (0.3% NAA) or Rhizopon AA (2% IBA). Both powders little affected rhizogenesis. Application of the biopreparation increased percentage and degree of rooting in dogwood as compared to control cuttings what shows its potential in a commercial production. The above treatment increased chlorophyll, carbohydrate contents and free amino acids in leaves of the sprayed cuttings.

Malus fruits are covered with peel, which consists of the cuticle, epidermis and several layers of hypodermis. This peel, and especially the cuticle and epicuticular wax formed on the fruit surface, plays a crucial role in preserving the fruit life by preventing water evaporation and the penetration of pathogen, as well as maintaining fruit firmness. The protective function of these two layers is particularly important after harvest during storage. Using light and scanning electron microscopy, the present study examined the structure of the fruit peel in two apple cultivars, ‘Lobo’ and ‘Boskoop’; their fruits had been stored for 2 months in a controlled-atmosphere storehouse. The fruit epidermis in cv. ‘Lobo’, with a smooth and slick surface, was characterized by the occurrence of unidirectional microcracks that were less numerous and had a smaller depth than in cv. ‘Boskoop’. The fruit surface in ‘Boskoop’ was coarse and dry, its numerous microcracks ran in different directions along the walls of the epidermal cells. Mycelium hyphae were observed in these microcracks and inside the lenticels of the fruits of ‘Boskoop’, whereas no mycelium hyphae were found on the surface of the fruits in ‘Lobo’. The apple cultivars differed in the thickness of the cuticle layer, the height of the epidermal cells as well as in the thickness and number of hypodermis layers.

Today, sustainable agriculture and food content is a very important issue in the world. Organic farming practices are very important in this respect.This study was made to observe the impact of organic agricultural regime on the products in case of haricot beans (Phaseolus vulgaris L.). A comparative study on elemental composition of various haricot beans (Phaseolus vulgaris L.) samples was conducted by using a sensitive method, wavelength dispersive X-ray fluorescence (WDXRF). 26 elements such as Al, Ca, Cu, Fe, As, Hg, Pb, Cd, Bi, Mn, Ni, P, S, Sr, Zn, Zr, La, Ti, Sn, Cl, K, Mg, Na, Ba, Rb and Si were determined in haricot beans samples (n=10) grown under organic and conventional farming regimes. The obtained results from each group were analyzed statistically by using SPSS statistic program. It was observed that the concentration and peak intensity values of Ca, Fe, Mn, P, Zn, Cl, K, Na, Mg and Si elements were higher in the haricot beans samples grown under organic farming regime. Likewise, Al and Sr levels were found in higher levels in the samples grown under conventional farming regime. Our findings clearly revealed that organic haricot beans are likely to have higher nutritional mineral content. And the haricot beans samples grown under conventional farming regime could contain harmful metals like Al and Sr that might damage the various systems and/or organs of humans and animals.

Arnica montana L., a valuable medicinal plant, has been used in the pharmaceutical and cosmetic industry for many years. Traditional methods of reproduction of this protected species are hardly efficient; hence, the method of in vitro culture provides the possibility of increasing the multiplication coefficient, which in turn would facilitate introduction of arnica into crop production. The aim of the study was to examine the effect of cytokinins and their concentration on multiplication of shoots and the effect of different concentrations of auxin on rooting of multiplied shoots of Arnica montana. The plants of mountain arnica were propagated from shoot tips placed on the MS agar (0.7%) medium supplemented with NAA (0.1 mg ·l^-1). One of the four cytokinins, i.e. BAP, KIN, 2iP and Z, was applied at the concentrations of 0.5, 1.0, 1.5 and 2.0 mg ·l^-1_. After 5 weeks of the in vitro culture, the shoots obtained were transferred to the MS agar medium supplemented with 0, 0.05_, 0.1 and 0.2 mg ·l^-1 NAA for rooting. The greatest number of the explants regenerating shoots and the shoots number were found in the MS medium supplemented with 0.5 mg·l^-1 BAP. KIN at the concentrations of 1.5 and 2.0 mg·l^-1 exerted the most substantial impact on the shoot length. No change in shoot length and weight was found in the case of Z, and a bigger number of shoots was obtained at its concentrations ranging 1.0 to 2.0 mg·l^-1. The shoots of the mountain arnica were characterised by high rhizogenic capacity. The biggest numbers of rooted shoots were found in the medium containing 0.1 mg·l^-1 NAA. Plants with the greatest number and weight of shoots were obtained in the same medium, while the longest roots were found at 0.05 mg·l^-1 NAA.

Poland occupies a prominent place in the cultivation of herbal plants. One of the main species is the marigold, which is widely used in pharmaceutical, cosmetic and food industry. In 2007–2009, a pot experiment was carried out in a greenhouse on cv. Radio pot marigold (Calendula officinalis L.). The experiment included two factors: nitrogen fertilization (g^.pot^-1): A – 0 (control), B – 0.3, C – 0.6 (0.6 + 0), D – 0.9 (0.6 + 0.3), E – 1.2 (0.6 + 0.6) and magnesium fertilization (g^.pot^-1): a – 0 (control), b – 0.5. The experiment demonstrated a significant effect of nitrogen fertilization on the number of pot marigold inflorescences. A significant increase in yields (versus the control) appeared after a dose of 0.6 g N^.pot^-1 was applied. In contrast, magnesium fertilization had a negative effect on all the analyzed traits.

In nursery production there are very few verified rootstocks for production of sweet cherry maiden trees. They do not always guarantee good growth results as well. GiSelA 5 and PHL-A seem to be very interesting ones, however, so far not well examined in a nursery. For a better adaptation of plants and improvement of condition for their growth, mycorrhizal fungus are used more and more often. In the experiment carried out in years 2007–2010 usefulness of four rootstocks and also of mycorrhization treatment for nursery production of maiden trees of two cultivars of sweet cherry trees was checked. The studies covered the following rootstocks: Prunus avium, Colt, GiSelA 5, PHL-A, and sweet cherry trees cultivars: ‘Sumit’ and ‘Vanda’, as well as mycorrhizal inoculum produced by companies: ‘Mycoflor’ (inoculum 1) and ‘Suplo’ (inoculum 2). Prunus avium rootstock grew the strongest in the nursery, the weakest one was PHL-A. Mycorrhization process, together with the application of inoculum 1 significantly influenced on the growth of rootstocks, but application of inoculum 2 did not significantly change results of growth compared to control group without mycorrhization. The most intensive growth of sweet cherry maiden trees was obtained on ‘Colt’ rootstock and the least on PHL-A. The best productivity of maiden trees was obtained on ‘Colt’ and PHL-A rootstocks and the worst on Prunus avium. Application of mycorrhization process positively influenced the diameter of maiden trees and their fresh mass.

Rhododendrons of evergreen leaves and rhododendrons of falling leaves (azaleas) are the most shrubs cultivated in modern gardens. Their values are not only decorative flowers but also leathery and glossy leaves. In a number of specimens during the vegetation season on leaves are visible blotch and necrosis, leading to their premature falling. Research was conducted in three successive vegetation seasons in gardens and parks in Malopolska. The object of research were the fallen leaves of rhododendrons and azaleas. For the mycological research 1500 infected leaves fragments was taken, and mycological isolation was performed according to standard methods used in phytopathology. From the fallen leaves of rhododendrons 1300 colonies of fungi, and from azaleas 1777 colonies respectively were isolated. Most frequently were isolated Alternaria alternata, Pestalotia sydowiana, P. truncata and Epicoccum purpurascens and fungi of the genera: Aspergillus, Fusarium, Mortierella, Penicillium, Phoma and Trichoderma.

White water lily Nymphaea alba L. is very popular among enthusiasts for aquatic plants cultivation in ponds. The decorative values are provided by magnificent flowers and attractive floating leaves. The aim of the study was to determine the health status of white water lily, and identificate of mycobiota accompanying those plants in the growing season, and thus causing symptoms of disease. The studies were carried out in twenty ponds, in 2006, 2008–2010. It was found that spots and necrosis of leaves were caused by complex of fungi and chromistan fungi from genera: Alternaria, Aspergillus, Cladosporium, Cylindrocarpon, Fusarium, Mortierella, Mucor, Paecilomyces, Penicillium, Phialophora, Phoma, Phytophthora, Pythium, Sordaria, Trichoderma and others. White water lily plants often were colonized by Alternaria alternata, Penicillium verrucosum v. verrucosum, P. expansum, Paecilomyces farinosus, Cylindrocarpon destructans, Sordaria fimicola, Mucor hiemalis f. hiemalis and Fusarium oxysporum. Fungi colonized the most intensively white water lily in the autumn. It was also ascertained, that since pathogenic fungi and chromistan fungi infected white water lily, such complexes brought about a range of spotting symptoms up to leaves necrosis, on account of what has taken place sharp decrease of plants aesthetic value.

The consumption of organic food has been growing all over the world. Clean soil environment and extensive methods of production make Poland particularly suitable for developing organic forms of farming. The nutritional quality of food grown by organic and conventional methods is the subject of much controversy. The nutritious quality of organic products is the subject of numerous scientific research. The study conducted in 2009 presents comparison of some nutritional values of juices made from organic and conventionally grown vegetables (carrot, red beet, celery). For the experiment 39 vegetable fields located in the south and east of Poland were chosen. All organic farms were certified according to UE Council Regulation no. 2092/91 and obtained valid certificates. Unclarified juices were obtained with cold press juicer. After microwave mineralization in HNO₃ the following nutrient elements were measured: P, K, Mg, Ca, S, Fe, Zn, Mn, Cu, B as well as Na, Cd, Pb, and Ni. Moreover, ammonium N and nitrates content were evaluated using FIA method. Celery juices were the richest in P, K, Mg, Ca, Fe, Zn, B and heavy metals Cd, and Pb, while carrot juices were having the highest level of S and Na. Cultivation methods significantly differentiated Ca, Mg and Na content. Generally, the conventional farming method favored higher accumulation of N-NO₃ (only in carrot), Mg and Na, whereas the higher Ca amounts were measured for bio juices. Significantly higher N-NH₄ amounts were observed for all conventionally vegetable juices than for organic. Higher levels of Cd were found for conventional juices made from carrot and beet, however in the celery juice the values differences were not significant.

Phomopsis diachenii belongs to the fungi recently detected on the herbs in the Polish climatic conditions. The purpose of this work was to study the fungus harmfulness to sowing material, seedlings, stems and leaves of caraway. The pathogenicity tests according to Koch’s postulates were carried out for 2 and 4 P. diachenii isolates using post-culture liquids, water suspension of conidia and discs of fungus sporulating mycelium to inoculate the plants’ parts. The studies were conducted both in the laboratory and a climatic chamber. P. diachenii caused disease symptoms in the form of necrosis on all plant organs tested. The ability for asymptomatic P. diachenii colonization of inoculated plants’ parts was determined. It was found that injuries of the plant epidermal tissue significantly increased the efficiency of inoculation. The performed pathogenicity tests and the results from electron microscopy SEM observation showed that the tested isolates of P. diachenii were occasional pathogens of caraway.

Previous research demonstrated positive influence of hydrophilic polymers on plant growth. Their utilization in agriculture is based mainly on mixing with the soil or medium. The aim of the experiment was to asses the influence of new form of supersorbent application in form of geocomposite consisted of polymer closed inside geotextile on development of Erigeron hybridus hort., Eupatorium purpureum L. and Silene chalcedonica (L.) E. Krause. The first factor of the experiment was utilization of geocomposite, the second one – pine bark mulching. After soaking in water geocomposite was placed in soil and plants were planted above. The growth and flowering of plants were assessed in the term of their most abundant flowering. The experiment documented positive influence of geocomposite on vegetative growth, it is: plant diameter and the number of shoots of all species as well as the height of Eupatorium. It also prompted Eupatorium and Erigeron flowering: plants developed more inflorescences of increased diameter. Pine bark positively determined the diameter of Eupatorium, whereas negatively influenced Silene diameter and number of shoots.

Temperature and light are important factors determining growth and development of plants. The difference between day and night temperature (DIF – defined as day temperature minus night temperature) influences plant morphology in a wide range of species. In this study, the effect of photoperiod and DIF on stem elongation and growth of dill plants was investigated. The first experiment included a comparison of different temperatures between day and night (DIF-5 – 20/25°C, DIF0 – 20°C and 25°C, DIF+5 – 25/20°C) for a 16-h photoperiod. The second experiment comprised the photoperiod of 16 and 24 hours for two constant temperatures – 20 and 25°C. Significant differences between DIF+5 and DIF-5 were observed in the case of plant height. Elongation growth was enhanced by positive DIF and was inhibited by negative DIF, although the strongest stem elongation inhibition was recorded at the temperature of 25°C and a 16-h photoperiod. Leaf area was greatly affected by the temperature and DIF, but only slightly influenced by the photoperiod. Leaf area in DIF-5 was smaller than that in DIF+5 or 0 (20°C). The highest essential oil content in the herbage was recorded for a constant temperature of 25°C as well as 20°C and a 24-hour photoperiod.

No-tillage cultivation with living mulch offers several benefits related to environmental protection and fulfills requirements of sustainable agriculture very well, however there are only few reports on vegetable cultivation using this method and referring to natural conditions of Poland. In three years field experiment stake tomatoes cv. Malinowy Ożarowski grown on no-tilled plots covered with wintering hairy vetch as a living mulch produced significantly lower total and marketable yield in comparison to conventional cultivation. Yield of fruits infested with potato blight was also significantly lower but their share in total yield was much higher. Content of carotenoids, monosaccharides and total sugars in fruits harvested under conventional cultivation was significantly higher and content of dry matter was significantly lower in comparison to no-tillage and content of vitamin C was independent of cultivation method. At time of full fruiting, leaves of tomatoes grown on plots covered with mulch contained more nitrogen, phosphorus and potassium and content of calcium and magnesium did not depend of cultivation method. Method of cultivation did not affect root-taking of potted tomato transplants but then tomatoes grown on plots covered with living mulch were dominated by hairy vetch and grew much slower till third decade of July when majority of vetch plants decayed. Growth of tomatoes in vetch mulch was much more differentiated during whole vegetation period. Living and then dry vetch mulch covered soil surface almost entirely and suppressed annual weeds well. Average decade temperature at 5 cm and 10 cm depth of conventionally cultivated soil was usually higher and soil moisture in 0–40 cm layer was significantly lower than those of soil covered with mulch. Cultivation method did not affect soil total porosity nor bulk density. At time of tomato planting, fresh and air-dry weight of hairy vetch was 39.7 t∙ha^-1 and 6.5 t·ha^-1 on an average respectively and it contained 180 kg N, 43 kg P, 209 kg K, 51 kg Ca and 12 kg Mg. Studied cultivation method offered several benefits related to environmental protection but was more management intensive and variable than conventional tillage.

Weed infestation depends on soil diaspore bank, the habitat conditions and the applied agricultural practices. Tillage constitutes one of the agrotechnical factors which significantly influence the condition and the level of weed infestation. In the conducted research, ploughless tillage practice and the application of herbicides considerably increased the number and the air-dry matter of weed populations per 1 m² of pea crop compared to plough tillage. It was also established that the number of weeds per 1 m² in the first term of weed infestation evaluation (in the phase of third true leaf) exceeded the number of weeds in the second term (ripening of pods and seeds). On the other hand, the air-dry matter of weeds was higher in the second term of evaluation. In addition, analyses revealed a higher number of weed species under the conditions of ploughless tillage (20–22 species) and herbicide application (20 species) than in the conventional tillage system (14–16 species). The predominant species under the conditions of conventional tillage were: Amaranthus retroflexus L. and Echinochloa crus-galli (L.) P.B. (in the first term of evaluation), and Avena fatua L. and Chenopodium album L. (in the second term). The predominant species in the ploughless tillage were: Echinochloa crus-galli (L.) P.B. and Amaranthus retroflexus L. (in the first term) as well as Fallopia convolvulus (L.) A. Löve, Avena fatua L. and Galinsoga praviflora Cav. (in the second term). In case of herbicide application, the prevailing species were: Echinochloa crus-galli (L.) P.B. and Matricaria inodora L. (in the first term) as well as Matricaria inodora L. and Echinochloa crus-galli (L.) P.B. (in the second term). The reduced tillage increased the number of perennial weeds: Cirsium arvense (L.) Scop., Elymus repens (L.) P.B. and Convolvulus arvensis L.

In a nursery production there are very few verified rootstocks diminishing the growth of sweet cherry trees in an orchard. An alternative solution is application of a dwarfing interstock. In the experiment the usefulness of a dwarfing interstock called ‘Frutana’ for the production of sweet cherry maiden trees was checked. The studies covered the following rootstocks: Prunus avium, and Colt and the cultivars of sweet cherry trees: ‘Kordia’, ‘Lapins’ and ‘Regina’. The strongest growth of sweet cherry maiden trees was obtained on ‘Colt’ and the weakest on Prunus avium with the interstock. The best productivity was obtained on Prunus avium, and the worst on Prunus avium with the interstock. Anatomic sections that were carried out did not show any signs of physiological incompatibility between the dwarfing interstock ‘Frutana’ and the studied cultivars of sweet cherry trees.

Curative and aromatic properties of basil herb make this species appear more and more frequently in field and glasshouse cultivations. Growth and yielding of basil plants depends, among others, upon the cultivar and fertilization. The experiment was conducted in a glasshouse, in the period from February to May 2009–2010. Plants were grown in pots of the capacity of 4 dm³, filled with peat substrate. Nitrogen (administered in the form of ammonium saltpeter) concentration in the substrate was differentiated: 0,2; 0,4; 0,6; 0,9 g N. dm³, as well as that of potassium: 0,4; 0,8 g K^. dm³, given in the form of a sulfate. The plants of three examined basil cultivars (Kasia, Wala, green leaved form) differed in average height, number of branchings, size of leaves, as well as the weight of fresh and air-dry herb. The application of nitrogen fertilization significantly differentiated the mean height and length and width of leaf blades in basil plants that decreased as the dose of this nutrient increased. Plants fed with the lowest and medium dose of nitrogen had significantly higher weight of fresh and air-dry herb, compared to the plants obtaining the highest dose. The amount of fresh herb of the examined plants remained under significant influence of the co-operation. The fresh herb weight of the examined plants remained under significant effect of cooperation between the cultivar and nitrogen dose. No significant effect of potassium dose was found upon the examined biometric features of basil plants. The interaction between nitrogen and potassium in the formation of basil growth and development was only demonstrated with reference to the height of plants and width of the leaf blade.

Plants of the family Brassicaceae are characterized by high nutritional and fertilization requirements, in particular with respect to nitrogen, potassium, and sulphur. The positive action of the above-mentioned nutrients on plant growth and yield is associated, among others, with their rate and form as well as with interrelationships between individual nutrients. The present experiment was conducted in a greenhouse during the period from March to May in the years 2010 and 2011. Garden rocket plants were seeded individually in 2dm³ pots, with peat as the growing medium. The experimental design included three rates (g dm^-3 of medium) of potassium in the form of K₂SO₄: 0.3 K (and 0.34 S); 0.6 K (and 0.47 S); 0.9 K (and 0.6 S), in the form of KCl: 0.3 K (and 0.27 Cl); 0.6 K (and 0.54 Cl); 0.9 K (and 0.81 Cl), as well as two rates of nitrogen in the form of Ca (NO₃)₂: 0.3 N (and 0.37 Ca); 0.6 N (and 0.74 Ca). The following traits were determined: plant height (cm), number of leaves per rosette (pcs), plant weight (g), and fresh weight yield of leaf rosettes (g ^. pot^-1). The content of N, P, K, Ca and of Mg, S-SO₄, Cl was determined in dried plant material. The increase in the rate of nitrogen in the nutritional environment of rocket did not affect plant height and the number of leaves per rosette, but it caused a significant increase in fresh weight yield of leaf rosettes, as well as it resulted in an increase in calcium content and a decrease in chlorine concentration in the plants. The increased amount of potassium in the medium contributed to an increase in rocket yield as well as an increase in the concentration of potassium and chlorine. Potassium chloride proved to be a better source of K than sulphur due to the amount of fresh weight and yield of the plants studied. The plants fed with KCl were also characterized by a higher content of nitrogen, chlorine, calcium, and magnesium than after the application of K₂SO₄.