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Open access

Ireneusz Ochmian, Jan Oszmiański, Bogusława Jaśkiewicz and Małgorzata Szczepanek

Abstract

The low availability of soils with an appropriate pH value (4.2-5.2) is a factor limiting an increase in highbush blueberry acreage. The experiments examined the influence of a physiologically acidic urea phosphate fertilizer on the pH change of the soil and the mineral content in the soil, leaves, and fruit as well as polyphenols in the fruit of two highbush blueberry cultivars – ‘Sunrise’ and ‘Brigitta Blue’. The fertilizer, at doses of 30 and 60 kg of nitrogen per hectare, was used in the experiments in each of the three years of the study.

After using 60 kg N ha−1, urea phosphate caused a reduction in soil pH. It also significantly influenced the total soil nitrogen content – the average for the cultivars was 7.40 mg in 2015, while in the control plots – 1.85 mg 100 g−1. These quantities are above the optimum recommended for highbush blueberry. At the same time, low amounts of this ingredient were found in the leaves (‘Sunrise’ – 1.83 mg; ‘Brigitta Blue’ – 1.77 mg 100 g−1).

Even after the application of 30 kg of fertilizer in the second year, the phosphorus content in the soil was at a high level (> 4 mg 100 g−1). The amount of phosphorus also increased in the leaves and fruit. Despite considerable quantities of available magnesium in the soil after urea phosphate application, a significant reduction of this component was observed in the leaves and fruit compared to the unfertilized control bushes. The applied fertilizer reduced the amount of polyphenols in the fruit of the tested cultivars.

Open access

Li-Hui Lü and Qiang-Sheng Wu

Abstract

Replant disease refers to the result of monoculture-continuous repetitive planting of congeneric crops or coordinal crops in the same soil for many years. Such disease is recognized as one of the main limiting factors affecting plant growth and production of horticultural plants in many countries. As a result, replant disease in horticultural plants has become a world problem in agriculture and also a bottleneck restricting the sustainable development of agriculture. In general, replant disease results in unfavorable growth of horticultural plants, which is due to allelopathy, autotoxicity, and the imbalance of both soil physical-biochemical traits and soil microflora. An environmentally friendly contribution to this could be bio-controlled by beneficial microorganisms. Arbuscular mycorrhizal fungi, one of soil-inhabiting fungi, can form a symbiotic association in roots to mitigate the negative effects of replant disease in many horticultural plants. Moreover, arbuscular mycorrhizal fungi do not produce any environmental pollution in soils and are a potential biological control. The soil fungi could regulate better morphological, physiological and molecular levels in plants to respond to the disease. This review mainly outlined the current knowledge in mycorrhizal mitigation of replant disease in horticultural plants, which appears to be a promising strategy to improve growth of horticultural plants in replant soils.

Open access

Agnieszka Wojtania and Bożena Matysiak

Abstract

The aim of the study was to develop an efficient micropropagation system for Rosa ‘Konstancin’, an interspecific hybrid between R. rugosa and R. beggeriana, whose fruits have high pro-health value. Shoot cultures were initiated from shoot buds collected in May and August from 15-year-old field-grown Rosa ‘Konstancin’ shrubs. The effect and interaction of different concentrations of phytohormones, sucrose and iron sources on in vitro initiation, multiplication and rooting of shoots were studied.

The time of collecting explants from donor plants significantly affected the initiation of shoot culture of Rosa ‘Konstancin’. Considerably higher frequency of bud break (100%) was obtained in explants isolated in August as compared to those collected at the end of May (30%). All buds developed into single shoots after 2-4 weeks of growing on the basal Murashige and Skoog medium containing 2.2 µM BAP, 0.3 µM GA3 and 88 mM of sucrose. The highest multiplication rate (4.8 shoots/explant) in a 5-week period was obtained on MS medium containing 50% of nitrogen salts, 3.1 µM BAP, 0.9 µM GA3 and 58 mM sucrose. High rooting frequency (100%) and quality of rooted plantlets was obtained on a medium containing 0.5 µM IBA, 138 µM Fe-EDDHA and 88 mM sucrose. Fe-EDDHA had a beneficial effect on the growth and photosynthetic activity of Rosa ‘Konstancin’ plantlets, which were successfully acclimatized ex vitro, with a more than 90% survival rate.

Open access

Ayesha Manzoor, Touqeer Ahmad, Muhammad Ajmal Bashir, Mirza Muhammad Qadeer Baig, Abdul Ahad Quresh, Muhammad Kausar Nawaz Shah and Ishfaq Ahmed Hafiz

Abstract

Gladiolus is one of the most important lucrative cut flower crops that is commercially cultivated worldwide due to its various spike forms, size, and shape and color combinations. In order to further increase the commercial and horticultural value by improving the ornamental traits of gladiolus ‘White Prosperity’, polyploidy was induced by soaking gladiolus corms in different colchicine concentrations (0.1%, 0.2% and 0.3%) for 24 h. Different colchicine concentrations had a little effect on sprouting and survival percentage but it significantly delayed the emergence of sprouts. About one third decreases in plant height along with reduction in number of leaves per plant, leaf area, length and width, chlorophyll content, diameter and number of cormlets per corm was observed in treated plants. Colchicine at 0.1% concentration improved the ornamental value of gladiolus by increasing vase life whereas colchicine at 0.3% was effective in increasing floret diameter. However, the colchicine treated plants exhibited delayed and reduced percentage of flowering corms. Pollen and stomatal study was done for the identification of polyploidy and it showed that both pollen and stomata size were increased while stomatal density and pollen fertility was significantly reduced in polyploid plants. Induction of polyploidy (mixoploids + octoploids) was achieved in all concentrations, however 0.2% and 0.3% concentrations of colchicine were effective for producing large number of polyploid plants. But at 0.1% concentration of colchicine, majority of plants did not show any change in their original ploidy level (tetraploid). These putative polyploids may be helpful for further improvement in ornamental and horticultural value of gladiolus.

Open access

V. Vetvicka and R. Fernandez-Botran

Summary

Immunosuppression caused by parasitic infections represents the foremost way by which the parasites overcome or escape the host’s immune response. Glucan is a well-established natural immunomodulator with the ability to significantly improve immune system, from innate immunity to both branches of specific immunity. Our review is focused on the possible role of glucan’s action in antiparasite therapies and vaccine strategies. We concluded that the established action of glucan opens a new window in treatment and protection against parasitic infections.

Open access

Oleksandr S. Potrokhov, Oleg G. Zinkovskyi, Mykola V. Prychepa and Yuryi M. Khudiyash

Abstract

Changes in the activity of Na+/K+-ATPase, lactate dehydrogenase, and succinate dehydrogenase in the white muscles and gill petals of roach, Rutilus rutilus (L), were studied for the combined actions of water mineralization and water temperature. It was established that decreased mineralization to 260.0 mg dm-3 and increased water temperature to 32°C increased aerobic processes in roach tissues. A sharp increase in water temperature and changes in water mineralization significantly affected the tolerance and physiological state of fish and could impact their abundance in waterbodies.

Open access

Lidia Dzierzbicka-Głowacka, Artur Nowicki, Maciej Janecki, Beata Szymczycha, Piotr Piotrowski, Piotr Pieckiel and Grzegorz Łukasiewicz

Abstract

As consumer awareness increases in Poland, fish consumption is on an upward trend. While new technologies permit meeting increasing demand, they significantly increase the pressure on fish supplies. As a result, many fish stocks are over-exploited, which threatens marine ecosystems. Declining fisheries, increasing fishing operating costs, and the necessity of making longer fishing expeditions at greater distances that often end with catches of fewer or less valuable fish mean that in some fisheries sectors are currently running at the margins of profit or at a loss. At the same time, the European Union’s fisheries policy aims to create more selective and sustainable fisheries, to implement limitations through fishing quotas, and to ban the recognition of discards. The aim is to ensure that individual fish species are protected while providing the European Union with stable, secure supplies of fresh fish. The FindFish Knowledge Transfer Platform project was launched to provide solutions for challenges facing commercial fisheries. Its purpose is to provide fishers with a knowledge transfer platform and a numerical forecasting system for the marine environment of the Gulf of Gdansk. By combining in-situ research, environmental data, fish catch data, and numerical calculations, this tool will improve the accuracy of targeted fishing while reducing by-catch. The system will provide more reliable data on fish stocks and facilitate more efficient resource management.

Open access

N. B. Terenina, N. D. Kreshchenko, N. B. Mochalova and S. O. Movsesyan

Summary

The serotoninergic and FMRFamidergic nervous system of the attachment organs of trematodes were examined using immunocytochemical techniques and confocal scanning laser microscopy. Adult trematodes from eight families as well as cercariae and metacercariae from ten families were studied. TRITC-conjugated phalloidin was used to stain the muscle fibres. The serotonin- and FMRFamide-immunoreactive (IR) nerve cells and fibres were revealed to be near the muscle fibres of the oral and ventral suckers of the trematodes and their larvae. The results indicate the important role of neurotransmitters, serotonin and neuropeptide FMRFamide in the regulation of muscle activity in the attachment organs of trematodes and can be considered in perspective for the development of new anthelmintic drugs, which can interrupt the function of the attachment organs of the parasites.

Open access

N. Kumari Gautam, P. Kumar Misra and A. Murari Saxena

Summary

Snakehead fishes are widely consumed throughout South East Asia, China and India because of their good taste of meat and high nutrient values such as presence of prostaglandins, thromboxane and Omega-6 fatty acid. Parasitic infection constitutes significant economic loss in fish production. The aim of this work was to study the seasonal variation of helminths in snakeheads. In the presented study, a three-year survey has been performed. A total of 1013 individuals of Channa punctatus and 247 individuals of Channa striatus were examined. A total of 3783 helminths were collected, with an average of 3.02 helminths/fish. 43.50 % individuals of C. punctatus and 59.10 % of C. striatus were found to be infected with acanthocephalans, trematodes, nematodes and cestodes per year. The prevalence and mean abundance of Pallisentis sp. was at its peak in summer. However the prevalence of trematodes, nematodes and cestodes was at peak during autumn. Mean abundance of nematodes was at peak in summer. Interestingly, the males were found more infected as compared to the females and the infection rate in males peaked in summer. In comparison to other weight groups, medium size hosts (21 – 40 g) were found more consistently infected. Thus the results indicate that there are seasonal variations in parasitic helminths infecting C. punctatus and C. striatus which also depend upon sex and weight. These variations may be attributed to various environmental and biological factors including parasite life cycle and immune level of host.

Open access

Muzaffer Mustafa Harlıoğlu, Ardavan Farhadi and Ayşe Gül Harlıoğlu

Abstract

The present status of freshwater crabs (Decapoda, Brachyura) in Turkey is reviewed in this study, with the purpose of identifying the exact number of species, their conservation status, and their distribution. In previous records, it was reported that Turkey has nine freshwater crab species belonging to the genus Potamon: Potamon bileki Pretzmann, 1971, P. ibericum (Bieberstein, 1809), P. hueceste Pretzmann, 1962, P. persicum Pretzmann, 1962, P. magnum Pretzmann, 1962, P. potamios (Olivier, 1804), P. setiger Rathbun, 1904, P. rhodium Parisi, 1913, and P. mesopotamicum Brandis, Storch & Türkay, 1998. However, there was no detailed information on species distribution in Turkey. This review is intended to update the distribution of species in the country, and it revealed that populations of three more freshwater crab species (P. karpathos, P. fluviatile and P. hippocrate) also occur; thus, there are currently 12 freshwater crab species in Turkey. In addition, this review provides a distribution map and identifies possible threats to each species. This review can serve decision makers in the development of management strategies to better protect the environments of these species that are facing growing anthropogenic impacts.