The principles of good agricultural and horticultural practice, which consider both giving environmental protection and high yielding of plants, require modern cultivation methods. Modern cultivation of horticultural plants uses, for example, cover crops, living mulches, plant growth-promoting microorganisms (PGPMs), plant growth regulators (PGRs) and other biostimulants protecting the soil against degradation and plants against phytopathogens and stress. The purpose of field and laboratory studies was to determine the effect of Trianum P (containing Trichoderma harzianum Rifai T-22 spores), Beta-Chikol (a.s.—chitosan), Timorex Gold 24 EC (based on tea tree oil) and fungicide Zaprawa Nasienna T 75 DS/WS (a.s.—tiuram 75%) on the health of carrot (Daucus carota L.) plants and the microorganism population in the rhizosphere of this plant. Moreover, the antagonistic effect of rhizosphere fungi on selected carrot fungal pathogens was determined. Laboratory mycological analysis allowed one to determine the qualitative and quantitative composition of fungi colonizing the underground parts of carrot plants. In addition, the total population of fungi and bacteria was determined (including Bacillus sp. and Pseudomonas sp.) based on the microbiological analysis of the rhizosphere soil. The application of the plant growth-promoting fungus (Trichoderma harzianum T-22), chitosan and tea tree oil positively influenced the growth, development and health status of carrot plants. T. harzianum T-22, chitosan and fungicide most effectively protected carrots against infection by soil-borne fungi from the genus Alternaria, Fusarium, Haematonectria, Sclerotinia and Rhizoctonia. The rhizosphere population of Bacillus sp. and Pseudomonas sp. in the treatments with Trianum P or Zaprawa Nasienna T 75 DS/WS was bigger than in the other experimental treatments. A reverse relationship was observed in the population of rhizosphere fungi. T. harzianum T-22, chitosan and tea tree oil promoted the growth of antagonistic fungi (Albifimbria sp., Clonostachys sp., Penicillium sp., Talaromyces sp. and Trichoderma sp.) in the carrot rhizosphere. Antagonistic activity of these fungi towards Alternaria dauci, Alternaria radicina, Sclerotiniasclerotiorum and Rhizoctonia solani was higher after the application of the preparations compared to control. Consequently, Trianum P, Beta-Chikol and Timorex Gold 24 EC can be recommended as plant biostimulants in ecological agricultural production, including Daucus carota cultivation.

The experiment was conducted in the Botanical Garden of UMCS in Lublin. A collection of three ecotypes of Allium ursinum L. from Dukla, Roztocze Region and Bieszczady mountain range, were the subject of our study. The aim of the study was to compare the biometrical features and chemical composition of garlic leaves. There were substantial differences both in growth characteristics and flowering characteristics of the ecotypes of Allium ursinum. The Dukla ecotype formed the longest leaves, whereas the shortest ones were found in the Roztocze ecotype. The Bieszczady ecotype was characterized by the widest leaf blades, the longest leaf stalk and flowering stems as well as the largest diameter of inflorescence. The Roztocze ecotype had the largest number of flowers in an inflorescence, while the Dukla ecotype had the shortest flowering stems and the fewest flowers in an inflorescence. The largest concentration of dry mass in leaves was detected in A. ursinum from Roztocze. The largest concentration of proteins was detected in the leaves of A. ursinum from Bieszczady. The most flavonoids were assayed in the leaves of the Roztocze ecotype of A. ursinum, the fewest in the Dukla one. Phenolic acids were at their highest concentration in the leaves of bear's garlic from Dukla, while the lowest concentration was recorded in the leaves of the ecotype from Bieszczady. The garlic leaves from Dukla had also the highest content of essential oil, while the Roztocze ones had the lowest oil content. The ecotypes of Allium ursinum differed substantially when it comes to the number of components of their essential oils and the amount of selected components.

The aim of the study was to determine the influence of cover crops biomass, mixed with the soil on different dates and with the use of different tools in field conditions. The cover crop biomass had a beneficial influence on the total porosity of the 0-20 cm layer of the soil after winter. The highest porosity was achievedwith cover crops of buckwheat, phacelia and mustard, the lowest with rye. During the vegetation period the highest porosity of soil was observed in the ridges. Among the remaining non-ploughing cultivations, pre-winter use of stubble cultivator proved to have a beneficial influence on the soil porosity, providing results comparable to those achieved in conventional tillage. The differential porosity of the soil was modified not only by the catch crops and the cultivation methods applied, but also by the sample collection dates, and it did change during the vegetation period. The highest content of macropores after winter was observed for the phacelia cover crop, and the lowest in the case of cultivation without any cover crops. Pre-winter tillage with the use of a stubble cultivator increased the amount of macropores in soil in spring, and caused the biggest participation of mesopores as compared with other non-ploughing cultivation treatments of the soil. The smallest amount of mesopores was found in the ridges.

A field experiment on fennel growing (Foeniculum vulgare var. azoricum Mill.) was conducted at the Experimental Farm of the University of Life Sciences in Lublin, on a grey-brown podzolic soil. The experiment included the following factors: three kinds of covers - soil covering with black polyethylene film (PE 0.05 mm), soil covering with black polypropylene non-woven fabric (PP 50 g m ^-2 ) and flat covering of plants with white polypropylene non-woven fabric (PP 17 g m ^-2 ); three sowing terms - April, May, June; two fennel cultivars - ‘Rudy F ₁ ’ and ‘Zefa Fino’. Soil mulching with PP50 and, to a slightly lesser degree, black PE, caused an increase in the total and marketable yield of fennel bulbs and had a favourable effect on the yield structure. The lowest yield, with the highest share of non-marketable bulbs, was obtained following plant covering with PP17. The bulbs were the largest in the experimental treatments with PP50 mulching. The smallest bulbs were harvested following PP17 plant covering. For fennel growing, the most favourable sowing time was April. The lowest yield was obtained from the June sowings. The cultivars studied did not vary in terms of yield level and structure. The bulbs of the ‘Zefa Fino’ cultivar were longer and more slender than those of the ‘Rudy F ₁ ’ cultivar

The aim of the experiment was to determine the influence of cover crop biomass incorporated into the soil at different times and using different treatments on carrot emergence and growth. 7 species of cover crops were included in the study: Secale cereale, Avena sativa, Vicia sativa, Sinapis alba, Phacelia tanacetifolia, Fagopyrum esculentum, and Helianthus annuus. Number of emerged carrot plants significantly depended on the cover crop used and on the method of pre-winter and spring pre-sowing tillage. Carrot emerged best after a rye or oats cover crop. Regardless of the cover crop species used, the largest number of carrots emerged in cultivation on ridges. In other variants of no-plow tillage, number of seedlings was significantly lower and did not differ from that under traditional plow tillage. The highest leaf rosettes were formed by carrot growing after a rye or oats cover crop. The highest rosettes were produced by carrots in the treatments where tillage was limited to the use of a tillage implement in spring and the lowest ones after pre-winter plowing. The effect of tillage on the emergence and height of carrot leaves largely depended on weather conditions in the successive years of the study. The largest number of leaves was found in carrots grown after a buckwheat cover crop and in cultivation without cover crop, while the smallest one after phacelia and white mustard. Carrots produced the largest number of leaves after a sunflower cover crop and the use of a tillage implement in spring, while the number of leaves was lowest when the mustard biomass was incorporated into the soil in spring. The use of cover crops significantly increased the mass of leaves produced by carrot as compared to the cultivation without cover crop. The largest mass of leaves was produced by carrots grown after the phacelia and mustard cover crops. Conventional plow tillage and pre-winter tillage using a stubble cultivator promoted an increase in the mass of carrot leaves.