Cover crops are increasingly adopted in viticulture to enhance soil quality and balance the vegetative and reproductive growth of vines. Nevertheless, this sustainable practice has been only recently used for table grape viticulture, with results often contrasting. The aim of this study was to assess the effect of a fescue (Festucaarundinacea Schreb.) cover crop on soil quality, yield, and grape qualitative parameters in a table grape vineyard (cv “Italia”) located in southern Italy, comparing results with the conventional tillage. Soil organic carbon (C), total nitrogen (N), microbial biomass C (MBC), β-glucosidase (BGLU) and alkaline phosphomonoesterase (APME) activities were assessed during three growing seasons (2012–2014) and three phenological stages. The trend of soil chemical and microbiological properties was jointly influenced by the soil management system, growing season and phenological stage. Compared to conventional tillage, cover crops increased, on average, soil organic C, total N, MBC, BGLU and APME by 136%, 93%, 112%, 100% and 62%, respectively. Slight or no effects of cover crops were observed on grape quality and yield, except for 2012 (the driest season), when a yield reduction occurred. This study reveals that cover crops strongly enhance soil quality in the short-term, with potential advantages for grape production in the long-term.
Four taxa of the Lamiaceae family growing in Apulia (Clinopodium suaveolens, Satureja montana subsp. montana, Thymbra capitata, and Salvia fruticosa subsp. thomasii) that had not been previously studied for their potential use in the food sector, were analyzed for their essential oils (EOs) composition and antioxidant and antimicrobial properties against some microorganisms, isolated from bread and bakery products, including molds (Aspergillus niger, Penicillium roqueforti) and spore-forming bacteria (Bacillus amyloliquefaciens and Bacillus subtilis). Two different sites were considered for each plant species, and the strongest antimicrobial EOs, which were active against all of the microorganisms tested, were those from one S. montana subsp. montana sample (Sm2) and both T. capitata EOs (Tc1 and Tc2) with Minimal Inhibitory Concentration (MIC) values ranging between 0.093% and 0.375% (v/v) against molds, while higher values were registered for bacteria (0.75–1%). In particular, the biological activity of EOs from T. capitata and S. montana subsp. montana was maybe due to the high amount of thymol and carvacrol, which were also responsible for the highest antioxidant activity. S. fruticosa subsp. thomasii EOs had different chemical profiles but showed only a slight antibacterial effect and no antifungal activity. C. suaveolens showed no significant changes between EOs with an interesting antifungal activity (MIC 0.093%÷0.187% v/v), which may be due to the presence of pulegone. These plant species can be considered as promising sources of bioactive compounds to be exploited as biopreservatives in bread and bakery products mainly considering the low concentration needed to inhibit microorganism’s growth.
The study focused on the effects of ecology (plant communities and topographical data) on composition of essential oils (EOs) of some officinal wild plant species (Lamiales): Clinopodium suaveolens, Salvia fruticosa subsp. thomasii, Satureja montana subsp. montana, and Thymbra capitata, in different environments of Apulia (Italy). C. suaveolens and S. fruticosa subsp. thomasii are rare species of conservation interest, while S. montana subsp. montana and T. capitata, have a wide distribution and are used in traditional medicine or as spices. Results showed that the ecological context (phytosociological and ecological features) may influence the composition of EOs of the studied species. High differences in the compound composition have been found in S. montana subsp. montana, whereas minor effects were observed in C. suaveolens, S. fruticosa subsp. thomasii, and T. capitata accessions. The understanding of such aspects is necessary for providing optimal conditions to produce EOs rich in compounds known for their biological activities. The results are of great interest also for EOs producers and at the same time to improve our knowledge and valorize wild officinal plants.
This study evaluated the effects of ecology (plant community, topography and pedology), as well as of climate, on the composition of essential oils (EOs) from two officinal wild plant species (Lamiales) from Apulia, namely Satureja cuneifolia Ten. and Thymus spinulosus Ten. Few scientific data on their chemical composition are available, due to the fact that the first has a limited distribution range and the second is endemic of southern Italy. Results for both species, never officially used in traditional medicine and/or as spices, showed that the ecological context (from a phytosociological and ecological point of view) may influence their EO composition, and hence, yield chemotypes different from those reported in the literature. S. cuneifolia and Th. spinulosus can be considered good sources of phytochemicals as natural agents in organic agriculture due to the presence of thymol and α-pinene. Overall, the obtained trend for EOs suggests a potential use of both species as food, pharmacy, cosmetics and perfumery. Hence, their cultivation and use represent a positive step to reduce the use of synthetic chemicals and to meet the increasing demand for natural and healthier products.
Essential oils produced by plants, and their components, could be sources of new natural herbicidal compounds. Thirteen oils extracted from six wild Lamiaceae species (namely Clinopodium suaveolens (Sm.) Kuntze, Satureja montana L. subsp. montana, Thymbra capitata (L.) Cav., Salvia fruticosa Mill. subsp. thomasii (Lacaita) Brullo, Guglielmo, Pavone & Terrasi, Satureja cuneifolia Ten., and Thymus spinulosus Ten.) from South Italy were tested in vitro for the phytotoxic activity to cress and branched broomrape seeds, tomato radicles, and lambsquarters leaf disks. Moreover, the possible correlation between oil composition and biological activity was evaluated. One of the oils from T. capitata inhibited cress germination by 96.4% at the lowest tested concentration (100 ppm) and reduced both chlorophyll and carotenoid content in lambsquarters leaf disks by around 50%. Some oils, particularly those from T. spinulosus, inhibited tomato radicle elongation by 85% at 1000 ppm. Many oils inhibited broomrape seed germination up to 100% when tested in solution at 1000 ppm or released as vapors. Among the oil components, α-terpinene, p-cymene, β-cis-ocimene, cis-sabinene hydrate, carvacrol methyl ether, and thymol were mostly correlated to the inhibition of cress seeds germination and tomato radicle elongation. The presence of thymol and p-cymene was also correlated to the inhibition of broomrape seed germination. Some of the tested essential oils or their components could have potential as pre-emergence herbicides and could be useful in the development of new weed control strategies.
2 January 2016 in Journal of the American Oil Chemists' Society