Volume 26 (2014): Issue 1 (June 2014)

The schemes for identifying and protecting the names of agricultural products and foods having specific qualities, have been launched by European Union as a part of its complex agricultural quality policy. The main objective of this article is to examine different aspects of three of the schemes, developed for products with specific characteristics resulting from a particular origin or farming method: PDO (Protected Designation of Origin), PGI (Protected Geographical Indication) and TSG (Traditional Speciality Guarantied). The focus is mainly on the economic issues of the production and marketing of products and foodstuffs registered under particular schemes. The methodology includes studying the existing literature and European regulations on the subject, collecting and analysing statistical data as well as examining a short practical case.

The economic theory suggests that PDO/PGI/TSG registration results in the higher ability of producers to compete in the market. The increasing number of registrations confirms the growing interest of producers in using it as a tool to create competitive advantage. However, a higher price for such products compared with a standard product, does not always translate into a market success, since producing them requires farmers to follow a certain specification and this may involve additional costs. The analysis of the Vistula Cherry case found that there are significant market opportunities for certified producers of high quality fruits due to excellent characteristics of their products, but at the same time they face certain external and internal challenges and need to further develop their production and marketing skills, within the framework of the local collective organization.

The high infestation rate of zinnia (Zinnia elegans Jacq.) seeds with fungi, especially pathogenic Alternaria zinniae, has frequently resulted in a poor germination capacity associated with a high number of abnormal diseased seedlings. The effect of hydrogen peroxide (H₂O₂) treatment on the germination, vigour and health of zinnia seeds was investigated. Two samples of zinnia seeds - sample I, characterised with a low germination capacity (39.5%) and a high level of seed infection with A. zinniae (76%), and sample II, with a high germination capacity (87%) and free from this pathogen - were tested. For treatment, seeds were soaked in 3%, 6%, 9% and 12% H₂O₂ solutions for 10, 20, 30 and 60 min. Initially, the controls were seeds soaked in distilled water for 10, 20, 30 and 60 min, and then the results of selected treatments were compared with results obtained for untreated seeds and seeds treated with a fungicide (20% carbendazim and 45% thiram). The fungi Alternaria spp. and Fusarium spp. were frequently identified on tested seeds. The concentration of hydrogen peroxide affected the quality of zinnia seeds to a higher extent than the treatment time. However, all of the treatments applied, regardless of time and concentration of H₂O₂, positively affected seed health, significantly reducing seed infestation by fungi in both samples. Moreover, the lowest level of A. zinniae infection was observed if seeds were soaked in 6% and 9% H₂O₂ solutions for 60 and 20 min, respectively. Higher concentrations of H₂O₂ (9% and 12%) negatively influenced seed germination and vigour, especially in sample II. These findings suggested that the treatment of zinnia seeds with hydrogen peroxide can effectively improve germination mostly in samples heavily infected with pathogens, which means that it should be preceded by seed health evaluation.

By maintaining proper moisture and reducing daily temperature fluctuations, mulching improves soil conditions for plant growth and development, resulting in a positive effect on the vegetable yield. The chemical composition of vegetables is genetically determined as well as being modified by factors affecting the plant during growth, and particularly climatic conditions and agro-technology practices. The effects of soil mulching with rye, corn, rape and buckwheat straw at a dose of 10 and 20 t ha^-1 on the yield and changes of selected components of nutritive value in ‘Milady’ F₁ broccoli and ‘Polfast’ F₁ tomato were investigated. The effect of straw was compared to a control plot without mulch. The yield of the vegetables and their chemical composition depended to a higher degree on weather conditions in the years of study. 2010 was the most favourable for broccoli yielding and 2011 for tomato. More nutrients components in heads and fruits were found in 2011 and 2012, which were characterised by favourable rainfall distribution. All straws applied in the experiment, irrespective of dosage, caused an increase in broccoli yield. However, soil mulching with straw at a dose of 10 t ha^-1 was better for tomato yielding. Soil mulching with rye, corn and buckwheat straw increased the share of marketable yield in the total yield of broccoli and rye straw as well as the share of marketable yield of tomato. Mulching with rape and buckwheat straw decreased dry matter content in the edible parts of the vegetables. Mulch with rye straw contributed to a decreased content of ascorbic acid in heads and fruits and also caused a slight reduction in tomato flesh acidity. However, soil mulching with corn and rape straw caused an increase in total sugars and monosaccharide content in broccoli and tomato.

The results of three years (2009-2011) of field studies using two types of biodegradable nonwoven covers (aromatic polyester IBWCH 75 g m^-2 and polylactic acid PLA 54 g m^-2) on the yield, quality and root development of cucumber are presented. Seeds of parthenocarpic cucumber (‘Mirabelle’ F₁) were sown directly into the field at the beginning of May/June and covered with nonwoven field covers. A plot that remained uncovered served as the control. The covers were kept in place until the first flowers appeared. Cucumbers were harvested every three days for 5-6 weeks. Fruits were evaluated for dry matter, soluble sugars and nitrate content. After the last harvest, whole plants were harvested and evaluated for weight, surface area, total length and average diameter of the roots. The experiment showed that the covers increased the marketable yield of cucumber in 2009 and 2010 (regardless of the type of polymer), but did not influence the yield in 2011. In 2011 the fruits from the covered plots had higher levels of soluble sugars and dry matter in comparison to the control. The covers did not influence root development.

In the years of 2012-2013 male-sterile cauliflower genotypes with the Brassica nigra cytoplasm and their maintainers were tested with respect to their ability for generative propagation and the quality of agronomical traits in comparison to male-fertile inbreeds and sterile genotypes with the Ogu-INRA cytoplasm. The ability for the generative propagation for male-sterile genotypes with the B. nigra cytoplasm was diversified and lower than for the maintainer, fertile lines and lines with the Ogu-INRA cytoplasm.

Generative stalks of cauliflowers with the B. nigra cytoplasm usually had a higher number of buds and flowers in comparison to the fertile genotypes and to the sterile Ogu-INRA lines. The most desired commercial characteristics, such as circular shape, compactness of curd and intermediate or strong coverage by leaves, were noticed for sterile lines with the Ogu-INRA cytoplasm and their fertile complementary lines. Three experimental F₁ hybrids showed good quality in comparison to commercial F₁ cultivars.

The purpose of this study was the evaluation of the pathogenicity of Plasmodiophora brassicae Wor. field isolates gathered from clubroot-infected white cabbage Brassica oleracea var. capitata L. f. alba plants grown in different areas of Poland. The virulence of seven isolates of the pathogen was tested. Breeding materials from white cabbage resistant and susceptible to P. brassicae were used as standard objects for isolate virulence screening. Cabbage seeds were infected by submerging them into a resting-spore suspension. A screening of plant resistance using a nine-degree scale based on root symptoms was carried out at the eight-week-old plantlets stage and at harvest time on afield infected by P. brassicae spores. Isolates from Pobiednik and Grębałów were defined as more virulent. The P isolate from Pobiednik also infested plants of the clubroot resistant ‘Kilaxy’ F₁ cultivar, which indicated the suppression of clubroot resistance. Its reaction to the other six isolates confirmed the resistance of this cultivar. The susceptible HTM line was characterised by the highest infestation level. A difference in the susceptibility level was noticed between lines derived from those with resistant genes, i.e. Oregon123 and ‘Badger Shipper’. The Oregon123 line was less susceptible to the applied isolates. The effect of the isolates used for seed inoculation on the reaction of the dormant plants to the pathogen on the clubroot field was observed.