Heracleum sosnowskyi Manden of the Apiaceae family is a malignant invasive plant in Eastern Europe, Belarus and Russia. The species is known for its prolific seed production, which has been linked to the plant's invasive success. The fruit also has a strong aroma, but the contribution of the fruit's volatile constituent to out-compete neighboring plants has not been fully established. In this study, fruit volatiles of H. sosnowskyi and conspecifics (i.e. H. asperum, H. lescovii, H. dissectum, H. hirtum) were identified by headspace gas chromatography-mass spectrometry (HS-GC-MS). Octyl acetate, octanol, octanal, hexyl isobutyrate, and hexyl-2-methyl butyrate were found to be the principal volatiles. Using authentic standards, the growth-inhibitory property of the individual compounds was assayed by the novel Cotton swab method. Assay results with lettuce (Lactuca sativa) showed that octanal strongly inhibited seed germination and radicle elongation of seedlings. The results suggest that octanal may be the main contributor to the allelopathic activity of H. sosnowksyi fruits. Furthermore, the mixture of fruit volatiles from the invasive H. sosnowskyi more strongly delayed lettuce seedling elongation than the volatiles from fruits of the non-invasive H. asperum, H. lescovii, H. dissectum and H. hirtum. Thus, the present study is the first to demonstrate the possible involvement of fruit volatiles of Heracleum species in plant-plant interaction.

Distribution patterns of furocoumarins in fruits of the invasive species Heracleum sosnowskyi Manden. (Sosnowskyi's hogweed) during a cold stratification period were investigated. Angelicin, bergapten, methoxalen and imperatorin were mainly localized in the fruit coats and their content varied depending on the fruit source. Cold stratification treatment (90 days, 2-3°C) reduced the content of furocoumarins in the fruit coats by more than two times, compared with those before stratification. The specific activity of the detected furocoumarins and total activity of crude extracts were evaluated using Lactuca sativa, as acceptor plant. Crude extracts obtained from fruit coats and seeds of H. sosnowskyi suppressed 50% of radicle and hypocotyl growth of lettuce seedlings at the concentration range of 1.0-1.7 mg/mL. The inhibitory activity of angelicin was proved to be the highest compared with the other tested furocoumarins, and the inhibitory activity of crude extracts could be explained mainly by the presence of angelicin. Both, monocots (Lolium multiflorum, Phleum pratensis, Festuca pratesis, Lolium perenne) and dicots (Tripholium repens, Trifolium pretense) were found to be sensitive to the exudates of whole H. sosnowskyi fruits. Thus, we assume, that high inhibitory potential of furocoumarins, especially angelicin, at high seed productivity of H. sosnowskyi might have an ecological significance in plant-plant interaction.

One hundred and thirty-nine medicinal plant species were screened for their allelopathic activity through volatile emissions using Lactuca sativa as a test plant. Volatile emissions from the leaves of star anise (Illicium verum) showed the highest inhibition (100%) on the radicle and hypocotyl growth. Using headspace gas collection and gas chromatography-mass spectrometry (GC-MS), seven major volatile compounds from the leaves of star anise, including α-pinene, β-pinene, camphene, 1,8-cineole, D-limonene, camphor, and L-fenchone were detected. To determine volatile compounds that may contribute to the inhibitory activity of star anise, the allelopathic potential of individual volatiles from star anise was evaluated using the cotton swab bioassay. The EC50 was calculated for each of the seven identified compounds. L-fenchone showed the strongest growth inhibitory activity (EC50 is 1.0 ng/cm3 for radicle and hypocotyl growth of lettuce), followed by 1,8-cineole, and camphene. This is the first report that L-fenchone could be an important volatile allelochemical from the leaves of star anise. From the actual concentration of each volatile compound in headspace and EC50 value, we concluded that the four volatile compounds, including L-fenchone, 1,8-cineole, β-pinene, and camphene are the most important contributors to the volatile allelopathy of star anise.

The antifungal activity of volatile compounds from the fruit, leaf, rhizome and root of 109 plant species was evaluated against Fusarium oxysporum f. sp. lycopersici (FOL) race 1—the tomato wilt pathogen—by using the modified dish pack method. Eighty-eight plant samples inhibited mycelial growth, including volatiles from fruits of Heracleum sosnowskyi, which exhibited the strongest antifungal activity, showing 67% inhibition. Two volatile compounds from the fruits of H. sosnowskyi (octanol and octanal) and trans-2-hexenal as a control were tested for their antifungal activities against FOL race 1 and race 2. In terms of half-maximal effective concentration (EC50) values, octanol was found to be the most inhibitory compound for both pathogenic races, with the smallest EC50 values of 8.1 and 9.3 ng/mL for race 1 and race 2, respectively. In the biofumigation experiment, the lowest disease severity of tomato plants and smallest conidial population of race 1 and race 2 were found in trans-2-hexenal and octanol treated soil, while octanal had an inhibitory effect only on race 2. Therefore, our study demonstrated the effectiveness of volatile octanol and trans-2-hexenal on the control of the mycelial growth of two races of Fusarium oxysporum f. sp. lycopersici and may have potential for the future development of novel biofumigants.

The most important task for the sustainable development of modern agriculture is to increase the biological diversity of cultivated crops. In recent years, due to global climate change, the possibilities of using more thermophilic crops in new agro-ecological zones have expanded. The problem of increasing the biological diversity of vegetable products largely depends on the introduction of non-traditional plant species, with a simultaneous assessment of the initial material for its use in economically useful purposes and the creation of varieties and hybrids adapted to local conditions. In this regard, Nigella L. is of great interest among rare plant species. It is one of the most famous spicy-aromatic crops in the Mediterranean and Central Asia, possessing a wide range of biologically active compounds and unique medicinal properties. The review article provides information on the origin, biological characteristics and breeding of the culture. A brief review of food, medicinal and other economically useful properties is given, as well as the main elements of the technology for growing nigella are considered. It is shown that the cultivation of this culture will provide an opportunity to expand the range of non-traditional plants and be a promising renewable source of valuable plant raw materials, which will find application in various fields: in agriculture, in the food, pharmaceutical, perfumery and cosmetic industries, as well as in ornamental gardening.