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Open access

Bożena Cwalina-Ambroziak and Maciej Nowak

The effects of biological and chemical controls on fungal communities colonising tomato (Lycopersicon esculentum Mill.) plants and soil

Tomato plants (Rumba Ożarowska cultivar) grown in the greenhouse of the University of Warmia and Mazury in Olsztyn were treated with the biological control agent Polyversum WP, the growth promoter Biochikol 020 PC, the growth regulator Asahi SL, a mycorrhizal inoculum, and the fungicide Bravo 500 SC. Untreated plants served as the control. After fruit harvest, soil, stem and root samples were collected, and fungi were isolated in the laboratory. The applied biological and chemical control agents effectively reduced the abundance of fungi, including pathogenic species, colonising tomato plants and soil. The fungicide Bravo 500 SC showed the highest efficacy. Amongst the biological control agents, Biochikol 020 PC and the mycorrhizal inoculum were most effective in controlling stem colonisation by pathogens, while Polyversum WP offered the best protection of tomato roots and soil.

Open access

S. Robbert Gradstein and Anna Luiza Ilkiu-Borges

Abstract

We describe the new liverwort species Lejeunea ryszardii from montane rainforest in the Central Cordillera of Colombia (Dept. Quindío) and Rectolejeunea halinae from submontane rainforest in the Western Cordillera (Dept. Risaralda). Both species stand out by copious vegetative reproduction via caducous leaves. Lejeunea ryszardii resembles the Caribbean L. paucidentata in the leaf lobes with toothed margins and a narrow base but strikingly differs from the latter species in: 1) leaf margins with mamillose cells, which are sometimes crowned by a small papilla, and with scattered rhizoids with or without a tooth-like base; 2) lobules with narrowly elongate, curved, sharp tooth; 3) stem epidermis brownish and somewhat thick-walled; 4) copious production of caducous leaf lobes. Moreover, L. ryszardii is dark green to brown in color and probably dioicous while L. paucidentata is light green and autoicous. Rectolejeunea halinae resembles the neotropical R. flagelliformis in having ciliate caducous leaves but clearly differs from the latter in the pointed leaf tips, the presence of ocelli in underleaves, and the flagelliform shoots with flat, entire-margined underleaves. The discovery of these new species adds two further endemic taxa to the rich bryophyte flora of the Colombian Andes.

Open access

Joacim Näslund, David Berger and Jörgen I. Johnsson

Abstract

This paper presents a study investigating performance of brown trout fry, with different behavioural characteristics, in environments differing in food predictability. Based on previous experimental findings, we hypothesised that more active individuals would be favoured by a predictable environment, as compared to an unpredictable environment, as a consequence of being more aggressive and likely to dominate the best feeding stations. This hypothesis was not supported, as more active individuals instead tended to perform better, in terms of growth and survival, in unpredictable environments. However, this effect may stem from initial size differences, as more active fish also tended to be larger. In predictable environments, no trends between activity (or size) and performance were detected. Dominant individuals could be identified based on lighter body colouration in 9 out of 10 rearing tanks, but dominance appeared not to be related to activity score. The results highlight a potential advantage of more active and/or larger fry in unpredictable environments, while performance in predictable environments is likely depending on other phenotypic characteristics. Our general experimental approach can be useful for further developments in the investigation of performance of different ethotypes of brown trout fry.

Open access

Anna Kapczyńska and Katarzyna Magdziarz

Abstract

Sundaville is the brand name of a new collection of cultivars of the genus Mandevilla (syn. Dipladenia), with the potential to become a leading vine in the world horticultural market. The research was carried out in order to analyse the growth of Sundaville ‘Pretty Red’ at different values of substrate pH (4.0, 4.7, 5.3 and 5.5). The study shows that flowers appeared after more than six months irrespective of soil conditions. Plants cultivated at pH 4.0 had the longest leaves, but at the highest substrate pH the widest leaf laminae were observed. Regardless of the substrate pH, the diameter of a single flower remained the same. Plants cultivated at a pH lower than 5.0 produced more flower buds and more flowers in comparison with the plants exposed to the higher pH. Moreover, pH < 5.0 positively affected the number of stems. The soil pH did not only affect the growth, but also the health of the plants. The lowest pH level (4.0) caused adverse changes to the leaves.

Open access

Arefeh Rahimi Shokouh, Ali Mehrafarin, Vahid Abdossi and Hassanali Naghdi Badi

Abstract

Plant enzymes, growth regulators and organic acids are the main groups of plant biostimulants (PBs), and their combined use in the final formulation may be important for increasing the quantitative and qualitative composition of plant products. This study aimed to determine the effects of a multienzymatic biostimulant (MB), indole-3-butyric acid (IBA), and citric acid (CA) on the morphological and phytochemical traits of bladder cherry (Physalis alkekengi L.). The treatments included different concentrations of MB (0, 0.5 and 1.0%), IBA (0, 25, and 50 ppm), and CA (0, and 500 mg dm−3), which were sprayed four times during the vegetative stage, at 12-day intervals, 35 days after planting. The results showed that the treatments had a significant effect on plant height, stem number, diameter and weight, leaf number and weight, fruit number, diameter and weight, the amounts of total phenols, alkaloids and flavonoids, and on the radical scavenging activity. The most effective formulation for improving the fruit yield of bladder cherry was 1% MB with 50 ppm IBA and 500 ppm CA. However, the best treatment for increasing the total phenolic and alkaloid contents, and radical scavenging activity was 0.5% MB. In general, the maximum values of most traits were obtained by spraying the plants with 0.5 and 1% MB combined with IBA and CA. The concentration of alkaloids, the main pharmaceutical metabolites of bladder cherry, increased as a result of the application of the multienzymatic biostimulant.

Open access

M. Azami, M. Anvarinejad and M. Jamshidian Ghalesefidi

Abstract

Matrix metalloproteinases (MMPs) represent a large family of over twenty different secreted or membrane-bound endopeptidases, involved in many physiological (embryogenesis, precursor or stem cell mobilization, tissue remodeling during wound healing, etc.), as well as pathological (inflammation, tumor progression and metastasis in cancer, vascular pathology, etc.) conditions. For a long time, MMPs were considered only for the ability to degrade extracellular matrix (ECM) molecules (e.g., collagen, laminin, fibronectin) and to release hidden epitopes from the ECM. However, expressions of many MMPs have been associated with several pathological conditions. It has been established that the MMPs are conserved throughout the animal kingdom and studies of invertebrate have demonstrated that primarily they are involved in various developing functions in hydra, Drosophila, sea urchin and nematodes. The syntheses of these proteolytic enzymes and their release as excretory and secretory products have been reported in various parasitic nematodes. Host invasion and tissue migration of several nematodes have been linked to the expression and release of parasite-derived proteases. Studies with enzyme inhibitors suggest that the enzyme may be a metalloproteinase. Moreover, substrate impregnated zymographic analysis of extracts and excretory and secretory products of different nematode parasites have revealed the multiple enzyme activities of MMPs with various molecular weights. More research on MMP degradome in nematode parasites can provide valuable information for intense evaluation of pathogenesis caused by these parasites.

Open access

Renata Wojciechowska, Ewa Hanus-Fajerska, Iwona Kamińska, Aleksandra Koźmińska, Olga Długosz-Grochowska and Anna Kapczyńska

Abstract

The southern African geophyte Lachenalia with an enormous number of species and cultivars is nowadays a commercially important plant material. There is a need for research on the optimization of growing conditions to obtain a satisfactory visual quality of potted plants, which may boost its production on the international ornamental market. Our research can be considered as an innovative study on supplemental irradiation with various light spectra in relation to flower quality of Lachenalia spp. The main objective was to examine the usefulness of LED lighting in extending the length of the natural day to a 16/8 h photoperiod in order to control the development of Lachenalia ‘Rupert’ inflorescence during greenhouse cultivation in Central-European winter time. Three light treatments were applied with red (660 nm) and blue (440 nm) light in different ratios: 100% red (100/0), 90% red mixed with 10% blue (90/10) and 80% red with 20% blue (80/20). The PPFD at the plant leaf level was approx. 150 µmol m−2 s−1. The most favourable spectrum, 90/10, induced the longest inflorescences characterized by the highest stem diameter with simultaneously the highest number of florets. Additionally, blue light increased the anthocyanin content in the corolla by about 35%, compared with plants exposed to 100% red light and non-irradiated ones (control plants). This first study on the wavelength ratios is aimed to increase the production quality of Lachenalia and indicates the need for continuation.

Open access

R. Sapierzyński and M. Czopowicz

Abstract

Canine osteosarcoma (OSA) is a malignant neoplastic tumor, which develops from the primitive mesenchymal stem cell, that has or can acquire the capacity to produce neoplastic osteoid with possible neoplastic bone formation. Predisposition of some dog breeds to OSA indicates genetic background of oncogenesis. The aim of the study was to characterize animal-dependent risk factors for canine osteosarcoma development in Poland. The study was conducted on canine patients diagnosed cytologically or histopathologically as having OSA, and data on age, breed, sex, as well as tumor location and character were recorded. No sex predisposition to OSA was observed, mongrels were significantly underrepresented. Large and giant dogs accounted for 47% and 35% of all pedigree dogs, respectively, and both proved predisposed to OSA. A vast majority of OSA developed in the skeleton (appendicular skeleton was more commonly affected than axial skeleton), soft tissues were affected less often. Rottweiler dogs are strongly predisposed to OSA, suggesting that the genetic background is involved in the tumor development, and indicates that dogs of this breed are a promising object for further studies on OSA pathogenesis.

Open access

Karl-Johan I. Bergstrand

-40. Bertram L., 1992. Stem elongation of Dendranthema and tomato plants in relation to day and night temperatures. Acta Hort. 327: 61-70. Bhattacharya A., Kourmpetli S., Davey M.R., 2010. Practical applications of manipulating plant architecture by regulating gibberellin metabolism. J. Plant Growth Regul. 29: 249-256. Cameron R., Wilkinson S., Davies W., Harrison-Murray R., Dunstan D., Burgess C., 2002. Regulation of plant growth in container-grown ornamentals through the use of controlled irrigation. Acta Hort. 630: 305

Open access

Eugeniusz Kołota, Katarzyna Adamczewska-Sowińska and Cecylia Uklańska-Pusz

ABSTRACT

During a three-year field experiment, the possibilities of cultivating the ‘Performer’ cultivar of Japanese bunching onion for early harvest bunching were assessed through the use of autumn and spring planting terms. The seedlings, produced in multi-pots, were planted in the open field on 8-10 September, 9-10 October and 6-12 April, and covered with a perforated foil and agrotextile in mid-November or directly following the spring planting. The covers were removed at the end of April, and the harvest of Japanese bunching onion was conducted at the end of May. The percentage of plants that survived the winter, how many produced flowering stems and the height of the total and marketable yield of plants with a pseudostem diameter >10 mm were determined. We evaluated the content of selected components with a nutritional value in samples of edible plant parts.

The results of the study showed that it is possible to obtain a high yield of plants harvested for bunches following an early spring term seedling planting. The majority of plants planted in the autumn froze during the winter, while those that were overwintered produced flower stems, especially if planted in September. The application of flat covers increased the percentage of plants that survived the winter, though in spite of this fact, the obtained marketable yield of Japanese bunching onion planted in the autumn was very low. Plants from the spring planting were characterised by a lower content of dry matter, chlorophyll a+b and volatile oils, while their content of K, Ca and Mg showed enhanced levels. Covering plants with a perforated foil positively influenced the content of total sugars and volatile oils, while negatively influencing the amounts of vitamin C, potassium and calcium as compared to those cultivated without covers.