This article is devoted to some aspects of the fragrant substances of plant origin applied in the food industry and perfumery as well. Since antiquity many extractive techniques have been developed to obtain essential oils. Some of them are still applied, but new ones, like microwave or ultrasound-assisted extractions, are more and more popular and they save time and cost. Independently of the procedure, the resulting essential oils are the source of many so-called isolates. These can be applied as food additives, medicines, or can be used as starting materials for organic synthesis. Some substances exist in very small amounts in plant material so the extraction is not economically profitable but, after their chemical structures were established and synthetic procedures were developed, in some cases they are prepared on an industrial scale. The substances described below are only a small fraction of the 2000–3000 fragrant molecules used to make our life more enjoyable, either in food or perfumes. Additionally, a few examples of allelopathic fragrant compounds, present in their natural state, will be denoted and some of their biocidal features will be mentioned as an arising “green” knowledge in agriculture.

Cultivation of spring cereal mixtures (SCMs) is one of the ways to increase the yield of crops in mountainous areas of Poland. There are only a few current long-term studies on this topic. Our study aimed at analyzing yield and competitiveness as well as the economic indicators of spring cereals in pure or mixed sowings in integrated or organic crop rotations over nine years. A field experiment including pure sowings of oats, spring barley, or spring triticale and their two-component SCMs, each in two systems, organic and integrated crop rotation, was carried out in the Mountainous Experimental Station in Czyrna, Poland, in the years 2011–2019. On average, cereals in the pure sowings and mixtures yielded 18% lower in the organic rotations compared with the integrated ones. However, SCMs yielded higher than the pure sowings, and displayed a higher leaf area index and land equivalent ratio. The average gross margin without subsidies was almost two times higher in the organic crop rotations than in the integrated ones, which was influenced mainly by the cultivation of barley in pure sowing. Summing up, the cultivation of SCMs in the mountainous areas of southern Poland is advised because of both productive and economic factors.

Agricultural production is a crucial part of policy issue in preventing depopulation of mountainous areas across Europe. However, soil and climate conditions are limiting yields and profitability of crop production in these regions. The European Union (EU) subsidizes agriculture in mountains by special payments (Less Favoured Area (LFA) subsidy) when areas match law-specified natural handicaps. This study aims to assess whether LFA subsidy in Poland is sufficient to cover losses caused by lower yields of crops cultivated in a mountainous region of Poland (Low Beskid Mountains in Carpathians) compared to lowland regions (non-LFA areas). The results indicated that LFA subsidy was adequate for crops (facultative wheat, winter wheat, field bean and spring barley) grown in the years 2015–2018.

Solidago canadensis L. is an expansive perennial that forms persistent, species-poor plant communities. It often spreads in fallow areas, displacing native floristic ingredients. Its expansiveness is largely due to morphological features, but it can also be the effect of allelopathic interaction. The aim of the experiment was to investigate the effect of aqueous extracts (decoction, infusion, and maceration) from dry S. canadensis leaves on germination and early growth stages of Raphanus sativus L. var. radicula Pers., in three cultivars: ‘Rowa’, ‘Półdługa’, and ‘Krakowianka’. In comparison to the control, the percentage of germinated radish seeds of ‘Rowa’ cultivar was statistically lower on the infusion and macerate. Regardless of the cultivar, the smallest changes in germination were found in seeds watered with decoction, and the largest with macerate. Seedlings length was most inhibited on macerate substrates, and least with infusion. Regardless of the form of the extract, each of them negatively affected the initial growth of radish seedlings. A fresh mass of ‘Rowa’ seedlings was inhibited by all Canadian goldenrod extracts. In relation to the control, the ‘Krakowianka’ cultivar was the least sensitive to S. canadensis extracts. The total chlorophyll content was the lowest in the seedlings of the ‘Rowa’ and ‘Półdługa’ cultivars germinated on macerate, compared to the control and two others extracts. The percentage of electrolyte leakage depended on the type of extract used and the radish cultivar. The study showed that depending on the cultivar, the aqueous extracts from S. canadensis leaves decreasing of germination and early growth of R. sativus.

In the cooler regions of Europe, the success of winter pea cultivation depends strongly on proper plant development before winter. Previous research has suggested that plants need to develop short internodes and at least their first two leaves before the arrival of frost. However, this stage of growth is sometimes not reached in the event of late sowing, due to factors such as unpredictable weather conditions or the delayed harvest of a previous crop. An effective solution may be the application of plant growth regulators before the sowing of seeds. The aim of this study was to assess the seedling developmental characteristics of winter pea dependent on biostimulator applications in low temperature conditions (4°C). Seven different winter pea cultivars were treated with three biostimulants: Asahi SL, Kelpak SL, and Primus B. After 21 days of seedling development, basic biometrical characteristics were measured (length and weight of shoots and roots). It was found that ‘Enduro’ and ‘Aviron’ showed greatest root development, regardless of the applied biostimulants. The highest germination was achieved by ‘Aviron’. The efficiency of biostimulators on the cultivars tested was low, although slightly better results were found for Asahi SL in combination with ‘Enduro’ and ‘Aviron’.

No abstract

The aim of this study was to investigate the effect of aqueous extracts from Chenopodium album L. on germination and early stages of triticale grains (×Triticosecale Wittm. ex A.Camus) and radish seeds (Raphanus sativus L.). Germination indexes, fresh and dry mass, water content and electrolyte leakage were measured. Studies revealed the different germination capacity of triticale grains and radish seeds, where increased concentrations of allelopathins in aqueous C. album extracts significantly inhibited seedling growth for both species. The extracts had an inhibitory effect on the growth of seedling fresh mass. An increase in dry mass of radish seedlings was demonstrated for each of the extracts and, for triticale seedlings, only at concentrations of 0.5% and 1.5%. Water content in triticale and radish seedlings varied depending on the concentration of allelopathins in the extract. With increasing concentrations of C. album extract, regardless of seedling type, a statistically significant increase in electrolyte leakage was observed.

The trophic activity of soil mesofauna, especially earthworms (the Lumbricidae family), is a key element in increasing the fertility of agroecosystems. Thee food strategies that earthworms use as part of the trophic networks in soil, and especially their food preferences, are still unknown. Much is known about what is the food substrate of earthworms, but the food preferences of individual species, as well as the possibilities and dynamics of food processing are not fully understood. The aim of the experiment was to observe the amount and dynamics of food uptake by the earthworms of the species Lumbricus terrestris L., which is a common species of soil Oligochaeta in agricultural areas, as well as to propose a new decomposition rate measuring the strength of the earthworm population and its contribution to the mechanism of processing plant organic matter.