The effect of BA and GA₃ on the yield and the quality of flowers and leaves of Zantedeschia was assessed in researches. The aim of the present research was to assess the effect of a mixture of benzyladenine and gibberellic acid in a solution used for rhizome soaking as well as of various duration times of this practice on the growth and flowering of the ‘Albomaculata’ and ‘Black Magic’ cultivars. In the experiment water solution containing benzyladenine at concentrations of 100, 350 and 600 mg·dm^-3 was used combined with gibberellic acid at a concentration of 150 mg·dm^-3. Rhizomes, 15–18 cm in circumference in 'Black Magic' cultivar and 20+ cm in 'Albomaculata' cultivar, with leaf buds 0.5–2 cm in length, were soaked for 30 and 60 minutes. Rhizome soaking in a BA and GA₃ mixture increased the yield of flowers in the ‘Black Magic’ and ‘Albomaculata’ cultivars, but delayed their flowering, and the flowers developing from rhizomes had shorter peduncles. Besides, in ‘Black Magic’ cultivar the weight of flowers decreased. The application of a BA and GA₃ mixture reduced the yield of leaves in ‘Albomaculata’ cultivar. However, they had a higher greenness index and a higher protein and sugar content.

Eggplant cultivars differ from one another in a number of properties, among others, earliness of fruiting and the length of fruiting period. A considerable problem regarding eggplant field cultivation in Poland is relatively high failure due to characteristics of our climate. Two-factorial field experiment established according to randomized split-plot method in three replications, aimed at the assessment of yielding of five eggplant cultivars: Avan F₁, Black Beauty, Classic F₁, Epic F₁ and Vernal F₁ (I factor). Plants were planted between 4^th– 7^th June, on the experiment years. Fruits were harvested in the stage of optimum harvesting maturity (every 7 days) and after exceeding this stage (every 10 days) (II factor). There was recorded significant diversity in eggplant yield in the years of the experiment, as well as in relation to its cultivar and the stage of fruit harvesting maturity. High temperature and sufficient amount of precipitation favored eggplant development in 2008, which was proved by yield (23.48 t ha^-1) higher than that in next years, average by 71.4% in the case of marketable yield and by 7.5 times higher for early yield (11.87 t ha^-1). Vernal F₁, Epic F₁ and Avan F₁ cultivars produced yield ranging from 23.79–18.89 t ha^-1, while Classic F₁ and Black Beauty featured yield lower by half. The marketable yield of elder fruits was higher than the one regarding fruits harvested in their optimum maturity stage. The results of chemical analysis proved that fruits in optimum maturity contained higher dry matter and reducing sugars in comparison to elder fruits. Yet no proof was found involving differences in biological value of the examined eggplant cultivars.

When producing bulb crops, height control is often required to obtain plants which are proportional to pot size. It regards particularly to forced tulips. An effective means of controlling plant height is the use of plant growth regulators. Research was conducted to define influence of flurprimidol on pot cultivation of forced tulips of ‘Arma’, ‘Ile de France’, ‘Juan’ and ‘Yokohama’ cultivars. Flurprimidol in concentrations of 7.5,  15.0, 22.5 and 30.0 mg^.dm^-3 was applied in the form of single and double spraying of the plants. The lowest plants with the shortest upper internodes resulted from double application of flurprimidol in concentrations of 22.5 mg^.dm^-3 30.0 mg^.dm^-3. The best effect in terms of inhibiting growth was achieved in case of ‘Juan’ and ‘Arma’ cultivars treated with a retardant in the above mentioned concentration. The applied dosage and frequency of application of flurprimidol are not sufficient to inhibit the growth of ‘Ile de France’ and ‘Yokohama’ tulips. It was noted that double spraying of tulips with flurprimidol in the concentration of 22.5 mg^.dm^-3 and both single and double spraying in concentration of 30.0 mg^.dm^-3 leads to the growth of the largest leaf with the smallest area index. It was also noticed that flurprimidol slows down slightly blooming of flowers and affects shortening of flower bud length.

We have obtained and described the nucleotide sequences corresponding to ilarvirus Prunus necrotic ringspot virus (PNRSV] coat protein (CP) gene in eleven Polish isolates, from different Prunus and Rosa species and four isolates provided in plant material from Australia, Hungary and Italy. Virus identification was possible using specific primers allowed amplifying the 700 bp amplicon of coat protein gene. The product was obtained used IC-RT-PCR. The results indicated no association between the host species or the geographic origin and the PNRSV CP sequence specificity. The CP gene nucleotide sequence of studied isolates allowed for clustering them into the previously reported PV32-I, PV96-II and PE5-III phylogroups.

Chamomilla recutita (L.) Rausch. is a wide known herbal plant which has many medical attributes and find applications in pharmacy, nutritional and sanitary industries. Estimating genetic diversity in population is very important to protect variety of chamomile species. The objective of this study was characterization of chamomile germplasm using ISSR markers. Among 20 screened ISSR primers, only 5 produced polymorphic and repeatable fragments. In total primers produced 48 fragments out of which 41 (85.4%) were polymorphic. The average PIC value for the amplification products was 0.340. Based on ISSR markers the genetic similarity matrices were produced. The mean genetic similarity was calculated at 0.653. Present study demonstrated that ISSR markers provided a practical and effective method to evaluate the genetic similarity and relationships of chamomile genotypes. Analyzed chamomile genotypes were characterized by quite high genetic similarity; it suggested that there is necessity to find new sources of genetic diversity in chamomile in wild populations.

New pseudostem cultivars of Japanese bunching onion may be a good alternative to common bulb onion grown for bunches in early spring season. There is still limited knowledge upon the requirement of this vegetable species for nitrogen fertilization. In two factorial field experiment, calcium nitrate, ammonium nitrate and Entec 26 – nitrogen mineral fertilizer containing DMPP nitrification inhibitor used as the source of N and applied at the rates of 75, 150 and 225 kg∙ha^-1 were compared. Seed propagated transplants produced in the greenhouse were planted in early April and harvested after 10 weeks of cultivation in the open field. The yield and nutritional value of edible parts expressed by the content of dry matter , vitamin C, total chlorophyll, carotenoids, volatile oils, total N, NO₃ – N, P K Ca and Mg were estimated. Results of the study proved that all tested fertilizers were equally valuable sources of nitrogen for Japanese bunching onion. The use of Entec 26 was associated with higher amounts of total chlorophyll and carotenoids in edible part of plants if compared to commonly recommended ammonium nitrate and similar to calcium nitrate. The other important advantage of this fertilizer was a substantial decline of nitrates content. The increment of preplant nitrogen rate from 75 to 150 and 225 kg∙ha^-1 did not affect the crop yield and significantly enhanced the nitrates accumulation in plants at harvest.

Tilia cordata is a good source of food attractants for bees. These insects are the primary pollinators of flowers of this species. Nectar is produced in the floral trichomatous nectaries located on a projection of the adaxial, basal part of the sepals. There were two types of non-glandular hairs on the sepals; the first one to prevent the nectar from flowing out beyond the sepal and the other type to protect the nectary itself. The clavate secretory trichomes, forming dense clusters, are composed of a base, stalk, and multicellular head. The secretory cells of the trichome head contain a thick cytoplasm and a large nucleus; they are also characterized by a low degree of vacuolation. Nectar accumulates at the tip of the trichome in the space formed between the cell wall of the head cells and the cuticle. The several-layered subepidermal glandular parenchyma with densely packed cells is provided with vascular bundles containing xylem and phloem. Plastids containing small starch grains were noticed in many cells of the nectariferous tissue, whereas phenolic compounds were found in the adaxial epidermal cells of the sepals. No presence of starch, lipids, or phenolic compounds was found in the cells of the glandular hairs. However, numerous chloroplasts, calcium oxalate crystals and large mucilage cavities occurred in the subglandular tissue.

The diversity of Zucchini yellow mosaic virus (ZYMV) isolates from cucumber and zucchini plants growing in different regions of Poland was analyzed using biological tests and molecular biology techniques. The isolates differed in their host range and symptoms induced by them on a series of plant species. In addition, the analysis of the genetic diversity of the coat protein (CP) gene revealed high level of nucleotide variability among the isolates. Comparison of the CP gene sequences of 70 isolates from different geographical regions worldwide showed that the Polish isolates belong to different groups and they do not form a monophyletic cluster with European isolates. Interestingly, among the central European ZYMV isolates lower variability has been observed previously. The ratio of nonsynonymous to synonymous polymorphic sites showed a dominant negative selection however codons which might undergo positive selection were also identified. Moreover, the evidences for recombination in analyzed sequences of the CP gene of the analyzed ZYMV isolates were provided.

The hybridisation of Vaccinium angustifolium with Vaccinium corymbosum has led to several cultivars which are also known as Lowbush or Half-highbush blueberry. The appearance, taste and chemical composition of their fruits are reminiscent of those from wild varieties of Vaccinium angustifolium. The research was conductedat the Research Station of the Laboratory of Orchard at the West Pomeranian University of Technology in Szczecin. The plant height, size, yield, quality and the chemical composition of fruits of Lowbush blueberry bushes (‘Emil’ and ‘Putte’) were determined. Lowbush blueberry bushes were planted at distances of 1.0 × 2.5 m in acid muck soil (peat) at the Research Station of the Fruit Farming Department in 2005. Six-year-old bushes were characterized by a relatively low height, 70 cm on average; however, ‘Putte’ cultivar plants were slightly bigger. They also rendered a higher yield, totalling to 1401 g over the 4 years of research. On average, 100 g of fruits were collected from one bush in the first year and 600–700 g in the last year. Moreover, fruits from these bushes were characterized by a higher content of extract, organic acids and polyphenolic compounds, among which anthocyanins constituted the largest group. ‘Emil’ cultivar fruits were bigger and firmer than fruits of ‘Putte’ cultivar.

The objective of the three-year study was to determine the influence of postharvest storage on essential and nonessential amino acids content in tubers of different cultivars of Jerusalem artichoke (Helianthus tuberosus L.) –‘ Rubik’, ‘Albik’ and ‘Sauliai’. The experiment was performed in 2007–2009. The plants were grown in the experimental field of Lithuanian University of Agriculture in Kaunas (from 2011 August – Aleksandras Stulginskis university). The Jerusalem artichoke tubers were stored for 20 weeks at the temperature of 2°C (±0.5°C) and RH 90–95 % in polypropylene (PP) perforated bags, capacity of 10 kg, in 4 replicates. Amino acids contents were determined immediately after harvest and during storage of the tubers in every 4 weeks by the method of ion-exchange chromatography and then detected photometrically. The data obtained were statistically analyzed with two-factor Anova (STATISTICA software). Standard deviation and the least significant difference at the 95% probability level were calculated with Fisher’s LSD test. Data presented in tables are mean values of the three years of the experiment. The results obtained showed that directly after harvest and during the storage the dominating amino acid in tubers of all cultivars was of essential amino acids – arginine, and of nonessential – asparagine, glutamine and alanine. Tubers of cv. ‘Sauliai’ after 20 week storage accumulated the highest amount of essential amino acids – treonine, valine, isoleucine, leucine, phenylalanine and nonessential – serine, glycine, alanine, tyrosine. Significant correlations between contents of some amino acids in the tubers were found.

Microscopic fungi are important in reducing of the quality of the herb material. This study concerns the fungi that may colonize the above-ground and underground organs of angelica (Archangelica officinalis). The study was conducted in the years 2008–2011 in the natural conditions of plant growth. Disease and etiological symptoms occurring on plants at the stage of 8-week-old seedlings, at anthesis and during the harvest were observed. T those dates the mycological analysis of the studied plants was conducted by artificial culture methods, taking into account schizocarps for sowing as well as the roots, stem bases and stalks, leaves, umbels and formed schizocarps. A total of 32 species of fungi, including those pathogenic to angelica and other herbs, were cultured and identified. These include species of the genera Colletotrichum, Phoma, Fusarium, Sclerotinia, Rhizoctonia, Ramularia and Phomopsis.

The colour of florets and leaves, considerably determining the decorative nature of plants, can depend much on the conditions throughout the period of cultivation. The research analysed the occurrence of anthocyanins and carotenoids in ray florets and chlorophylls in leaves in Chrysanthemum × grandiflorum /Ramat./Kitam., ‘Baton Rouge’ grown in the glasshouse over 2010–2011. The plants were exposed only to short day induced by darkening, applying no supplementary lighting of the plants. From the ray floret tissues carotenoids were extracted using concentrated acetone and anthocyanins with 1% HCl in methanol, whereas to extract chlorophylls a and b from leaf explants, concentrated acetone was used. The samples with extracted pigments were exposed to studies applying the spectrophotometer UV-VIS 1601-PC at the wavelength corresponding to the maximum of the band of a given pigment. For carotenoids the wavelength was λ= 440 nm, for anthocyanins: λ= 530 nm, whereas for chlorophylls: λ= 645 and 663 nm. There was also defined the colour of ray florets and leaves applying the RHSCC Colour Chart [1966]. It was found that the date of plant planting, and thus their flowering, affects the concentration of pigments: anthocyanins and carotenoids in ray florets and chlorophylls in leaves and, as a result, also their colour. The highest concentration of anthocyanins was reported in the plants planted into pots on 1.12., 1.01 and on 1.07., carotenoids in the growing cycles launched on 1.11., 1.12., 1.01, 1.03, 1.07 and 1.08., while chlorophylls a and b – on 1.03.

Productivity of plants is determined by multiple factors that directly affect one another, therefore yield variability may be high and difficult to predict. Most often, however, a lower crop yield is achieved in the no-tillage system than in the ploughing system. The reported study evaluated the yielding of pea under conventional (ploughing) tillage (shallow ploughing and harrowing after harvest of the previous crop, ploughing in the autumn), reduced tillage (only cultivator after harvest of the previous crop) and herbicide tillage (only Roundup 360 SL after harvest of the previous crop). The highest pea yield was achieved in the conventional tillage, whereas a lower one – by 40.8% – in the herbicide tillage. The conventional tillage system increased the number of pods per 1 m², the number of grains per 1 m², and grain weight per plant, compared to the herbicide tillage. The yield of pea was correlated with pod number per 1 m², grain number per 1 m², grain weight per plant, and plant number per 1 m². Correlations were also confirmed between pod number per 1 m² and grain number per 1 m², as well as between plant number per 1 m² and pod number per 1 m², and between plant number per 1 m² and grain number per plant.

Transplant quality of tomato depend on such factors as microclimate parameter, substrate, plant nutrition and other. The growth stage is very important indices of their quality. The objective of research was to determine the effect of the growth stage of tomato transplants on their quality and yield. Research was carried out in a greenhouse of the Institute of Horticulture, Lithuanian Research Centre for Agriculture and Forestry in the period of 2008–2010. The investigated transplant growth stage of tomato cv. Cunero F₁ 5–6 leaves, 7–8 leaves and 9–10 leaves. Tomato transplants with 9–10 leaves were elongated and their leaves area were the highest. Plants with 7–8 leaves according to stem and leaves ratio were qualitative, accumulated in leaves the highest content of photosynthetic pigments and had the highest SLA. Tomato transplanted with older transplant started to flower the fastest compared to 5–6 leaves transplant. Higher total yield was produced by 7–8 leaves transplants. The least early yield was produced by 5–6 leaves transplant. The growth stage of tomato transplants had no effect on the average tomato fruit weight.