No abstract

The effect of different sulfate(VI) sulfur (2, 6, and 9 mM S) levels and nickel(II) chloride (0, 0.0004, 0.04 and 0.08 mM Ni) in the nutrient solution on productivity and macronutrient (N, P, K, Ca, Mg, S) status and accumulation in spring wheat (Triticum aestivum L.) Zebra cv. was studied. Ni treatment reduced the biomass and disturbed the balance and accumulation of macronutrients in wheat. Intensive S nutrition, especially with 6 mM S, at least partially increased the biomass, improved ionic equilibrium, and enhanced nutrient accumulation in Ni-exposed plants in spite of increased Ni accumulation. Admittedly, the dose 9 mM S reduced Ni accumulation in shoots but increased accumulation thereof in roots. Compared to 6 mM, the dose 9 mM was less effective in improving the mineral status of Ni-treated wheat.

The seedlings of the soybean (Glycine max. (L.) Merr.) cv. Polan were investigated by subjecting them to water culture for a period of 14 d. To the Knop nutrient solution, lead was added as PbCl2 at four concentrations: 0, 10, 20 and 40 mg dm−3. Observations of soybean leaf tissues were carried out by light microscopy, transmission electron microscopy and scanning electron microscopy. The Pb levels used in the present study reduced the area of cotyledons and leaf blades of the soybean plants. Pb‐induced changes in the leaf epidermis structure involved a reduction in the cell size, more abundant wax coating, and an increase in the number of stomata and trichomes per unit area with simultaneous reduction in the size of the guard cells. The lead treatment resulted in the reduction in the thickness of the leaf blades, reduction in the area of xylem and phloem in the vascular bundles and in the diameter of the xylem vessels. Under Pb stress, the leaf mesophyll cells were characterized by the presence of altered chloroplasts with a reduced lamellar system and multidirectional pattern of the thylakoid system. Burst stroma of the thylakoid system and cracked chloroplast envelopes were also observed. The importance of the increase in the number of stomata and trichomes for plants under the metal stress was examined.

The Polemoniaceae family forms flowers diverse in the terms of pollination methods and nectar types. The micromorphology of the nectary surface and the tissue structures as well as the ultrastructure of the cells of the floral nectaries in Polemonium caeruleum L. were examined using light, scanning and transmission electron microscopy. A bowl-shaped nectary, detached from the ovary, grows at its base. Its contour shows folds with depressions in the places where the stamens grow, forming five-lobed disc (synapomorphic character). Nectar is secreted through modified anomocytic stomata, which are formed in the epidermis covering the tip and the lateral wall of the projection located between the staminal filaments. The undulate nectary consists of a single-layered epidermis and three to nine layers of parenchymal cells. The cells of the nectary contain a dense cytoplasm, numerous plastids with an osmophilic stroma and starch grains, well-developed endoplasmic reticulum, as well as a large number of mitochondria interacting with the Golgi bodies. The ultrastructure of nectary cells indicates the granulocrine secretion mechanism and diversified transport of nectar.

There is very scanty information concerning the floral nectary structure and nectar secretion in Prunus laurocerasus L. Therefore, the aim of the study was to determine the micromorphology, anatomy and ultrastructure of nectaries; the abundance of nectar production; and the quantitative and qualitative composition of sugars contained in the nectar of two P. laurocerasus cultivars: ‘Schipkaensis’ and ‘Zabeliana’. The nectary structure was studied using light, fluorescence, scanning and transmission electron microscopy techniques. The nectar sugars were analysed with HPLC. The ‘Schipkaensis’ had longer inflorescences with a larger number of flowers and a longer perianth than ‘Zabeliana’. The micromorphological structure of the nectaries in ‘Schipkaensis’ exhibited denser (approx. 39%) and larger (approx. 50%) stomata and thicker (approx. 13%) cuticular striae forming wider bands (approx. 26%) than in ‘Zabeliana’. The results provide new data on the micromorphology, anatomy and ultrastructure of these floral nectaries. Nectary cuticle ornamentation as well as the size, type and density of stomata and stomatal complex topography can have a diagnostic value in Prunus. The nectar sugar weight indicates a significant apicultural value of the cherry laurel, especially in the case of ‘Schipkaensis’. Cherry laurel is an entomophilous species recommended for cultivation in nectariferous zones and insect pollinator refuges; however, climatic conditions eliminating the invasiveness of these plants should be considered.

In Poland, the genus Rubus comprises 95 species. Given the commercial production of the fruits as well as their medicinal properties and apicultural and ornamental importance, raspberries are commonly cultivated plants of great economic value. Rubi idaei folium exhibits a wide spectrum of pharmacological activities. The aim of the present study was to determine the content of some bioactive compounds and compare the antioxidant activity in R. ideaus leaves. The highest and lowest content of chlorophyll was found in the 'Laszka' and 'Glen Ample' varieties, respectively. The content of total fat, carbohydrate, and total protein was 2.1%, 6.2%, and 20%, respectively. Saturated fatty acids were dominated by palmitic, arachidonic, tetracosanoic, and stearic acids. Omega 3, omega 6, and omega 9 acids were mainly represented by α-linolenic acid, linolenic acid, and oleic acid, respectively. The highest antioxidant activity was determined in the leaves of the 'Radziejowa' variety, and the lowest level was found for the 'Glen Ample' variety. The high antioxidant activity and the content of bioactive compounds indicate that raspberry leaves can be used as drinkable infusions or extracts applied as additives to some food products.

A b s t r a c tThe intensely fragrant flowers of the Rosa rugosa Thunb. have been applied in medicine, and food and cosmetic industries. The species is cultivated for production of rose essential oil (Oleum Rosae) from its flowers. R. rugosa petals secrete the largest quantities of essential oil.The aim of the study was to identify the characteristics of the epidermis of both sides of the petal and to observe whether adaxial and abaxial epidermal cells can secrete essential oil. The investigations were conducted using light and scanning electron microscopy. The analyses were focused on petal thickness and characteristics of the mesophyll. The study has demonstrated that only adaxial epidermal cells form conical papillae covered by massive cuticular striae. The surface of the papillae displayed remnants of a secretory substance. In turn, the inner walls of the abaxial epidermal cells were flat and covered by a striated cuticle, which exhibited various striation patterns. Fragrant substances stored under the cuticle caused local stretching thereof and disappearance of striation. The results of our observations allow a statement that the cells of the adaxial and abaxial epidermis of R. rugosa petals differ in terms of the structure and they secrete fragrant substances.

In Poland <em>Galanthus nivalis</em> L. is partially protected. The flowers of this species are one of the first sources of nectar and pollen for insects from February to April. The aim of this study was to present the flowering biology as well as the topography, anatomical, and ultrastructural features of the floral nectary. The flower lifespan, the breeding system, and the mass of pollen and nectar produced by the flowers were determined. Examination of the nectary structure was performed using light, fluorescence, scanning and transmission electron microscopy. The flower of <em>G. nivalis</em> lives for about 30 days. The stamens and pistils mature simultaneously and during this time nectar is secreted. The anthers of one flower produced the large amount of pollen (4 mg). The breeding system of <em>G. nivalis</em> was found to be characterized by partial self-compatibility, outcrossing, and xenogamy. The nectary is located at the top of the inferior ovary. The nectary epidermal cells are characterized by striated cuticular ornamentation. Initially, the secreted nectar formed vesicle-like protuberances under the cuticle. The epidermal and parenchymal cells contain numerous plastids, mitochondria, dictyosomes, ER cisterns, and vesicles fused with the plasmalemma, which indicates granulocrine nectar secretion.