Mycobiota development during matriconditioning of onion seeds.

Physiological seed conditioning is applied to improve and enhance seed performance. The treatment is based on prolonged hydration. It creates suitable conditions to pathogenic seed-borne mycophlora development. One of the conditioning method which employs the matric properties of solid water carrier is matriconditioning. In this procedure seeds are subjected to hydration for several days. The aim of research was to examine mycophlora development during matriconditioning and to find out, if commonly recommended chemical seed treatment is effective in seed protection.Following treatments were used: untreated – control seeds „C”, seeds treated with chemicals (carbendasim, thiram, metalaxyl and carbosulphate) – „C+CH”, seeds matriconditioned with Micro Cel-E – „MC” and seeds treated with above mentioned chemicals and then matriconditioned (MC+CH). Fungi isolation and development were conducted on medium and fungi diagnosis was taken under light microscopy.The results revealed stimulating effect of matriconditioning on pathogenic and saprophytic fungi occurrence on onion seeds. Significant differences between isolated fungi were observed in comparison to control. In population of mycophlora isolated from matriconditioned seeds, high percentage of occasional parasites were observed such as Alternaria porri, Alternaria tenuis as well as fungi of species Botrytis and Penicillium. Matriconditioned seeds were more infected by all above mentioned fungi. In vitro, fungicides showed differentiate effect on pathogenic and saprophytic mycophlora, from almost total control up to a high tolerance. The lowest seed infection presented C+CH treatment- it is chemical control with no matriconditioning. Chemical seed treatment applied before matriconditioning improved seed health status of matriconditioned seeds (MC+CH)

The effect of companion plants on Lygus feeding damage to bean.

The aim of research was to find out the protective effect of companion plants against lygus bugs (Lygus spp.) in organic production of bean (Phaseolus vulgaris L..). The field experiment was conducted during 2004 and 2005. Bean were sown on three dates: May 10, 25, June 10. As companion plants the following species were applied: red beet (Beta vulgaris L.), dill (Anethum graveolens L.), marigold (Tagetes erecta L.) and sage (Salvia officinalis L..). At harvest the bean seeds were examined for the presence of seed-pitting caused by lygus bugs. The lowest percentage of damaged seeds, demonstrated the samples obtained from plots cultivated in the close proximity of dill and marigold The number of pitted seeds depended on the date of seeds sowing and the year of experiment

The Effect of Plant Growth Promoting Bacteria on Transplants Growth and Lettuce Yield in Organic Production

Application of beneficial bacterial strain B125 (Enterobacter sp.) and strain PZ9 (Bacillus sp.) in lettuce transplants production significantly enhanced seed germination and plant biomass. The best effect was obtained when the mixture of B125 and PZ9 was used. Combined application of these bacteria significantly increased transplants biomass, which was about 45% higher than that in the control. However, after planting these transplants in organic field, generally, there were no differences in yield and nutrient content in plants treated and not treated with the bacteria, except for nitrogen and vitamin C. The lettuce grown from transplants treated with bacterial mixture B125 + PZ9 contained significantly higher nitrogen than plants from other treatments. Opposite to nitrogen, bacterial applications decreased the amount of vitamin C. The growth and organic lettuce composition was affected by planting time. The yield was higher in spring, but the concentration of nutrients in these plants was lower than that in plants harvested in autumn. Climatic and light conditions in the late season were the reasons for increased dry matter content, minerals, phenolic compounds, and vitamin C, as well as high concentration of nitrates

The Effect of Organic vs. Conventional Cropping Systems on the Yield and Chemical Composition of Three Courgette Cultivars

Courgette is a popular vegetable belonging to the Cucurbitaceae family. It is known for its good adaptation to different weather conditions, although it performs best in a warm and humid climate. Since the yield and various quality characteristics of vegetables are known to be strongly influenced by a number of weather, agronomic, and genetic (variety/cultivar) factors, in this study we aimed to compare three cultivars of courgette (Atena, Lajkonik and Soraya) grown in two consecutive growing seasons in the organic and conventional agronomic systems. The concentrations of nitrates, nitrites, carotenoids (lutein, zeaxanthin, β-carotene) and chlorophylls (chlorophyll a, chlorophyll b) in courgette fruits were analyzed by HPLC. The growing season had a predominant effect on the yield as well as the majority of the analyzed compositional parameters of the courgette fruits. The studied cultivars differed significantly in the concentration of lutein, β-carotene, and chlorophylls, although some significant interactions between the cultivar and the growing season were observed. On average, organically grown courgettes were characterized by a significantly higher yield, as well as higher dry matter and chlorophyll content, however, this agronomic system’s effect was not consistent among all the studied cultivars in the two seasons. The study suggests that organic practices have a potential to provide high yields of good quality crops, comparable (or, in the case of some parameters, better) than the conventional, resource-intensive horticulture