Impacts of the substrate medium on tomato yield and fruit quality in soilless cultivation

The performance and suitability of different substrates for the soilless culture of tomato plants (Lycopersicum esculentum Mill., cv. Belladona) were studied over a 5-month period in a closed soilless culture system employing five different substrates (perlite, pumice or maize and their mixtures with 50% shredded maize stems in an unheated glasshouse). Plants grown in a maize stem-containing medium produced earlier fruits, followed by pumice. Plants grown in pumice and perlite substrates obtained lower total yield; a higher yield was associated with the addition of maize shredded stems. Pumice + 50% maize and 100% maize produced higher total number of fruits per plant. Fruit quality parameters such as mean fruit weight, fruit firmness, total soluble solids, titratable acidity, ascorbic acid and carotenoids were influenced by the treatment, while EC, pH and dry matter content were not. The results suggest that the addition of maize in perlite and pumice could improve inorganic substrates properties for tomato soilless culture, leading to higher yields and better fruit quality

Impacts of the substrate medium on tomato yield and fruit quality in soilless cultivation

The performance and suitability of different substrates for the soilless culture of tomato plants (Lycopersicum esculentum Mill., cv. Belladona) were studied over a 5-month period in a closed soilless culture system employing five different substrates (perlite, pumice or maize and their mixtures with 50% shredded maize stems in an unheated glasshouse). Plants grown in a maize stem-containing medium produced earlier fruits, followed by pumice. Plants grown in pumice and perlite substrates obtained lower total yield; a higher yield was associated with the addition of maize shredded stems. Pumice + 50% maize and 100% maize produced higher total number of fruits per plant. Fruit quality parameters such as mean fruit weight, fruit firmness, total soluble solids, titratable acidity, ascorbic acid and carotenoids were influenced by the treatment, while EC, pH and dry matter content were not. The results suggest that the addition of maize in perlite and pumice could improve inorganic substrates properties for tomato soilless culture, leading to higher yields and better fruit quality

Effect of solution conductivity on the volatile constituents of Origanum dictamnus L. in nutrient film culture

The chemical composition of the essential oils obtained from leaves and bracts of hydroponically cultivated Origanum dictamnus L. (Cretan dittany), growing under various electrical conductivity (EC) levels (2.0, 4.0, and 6.0 mS/cm), was studied, using the nutrient film technique (NFT). The analysis of the essential oil content was achieved by GC-MS technique, and totals of 41 and 38 different compounds were identified in both cases of large-leaved and narrow-leaved samples of leaves and bracts, respectively. Differences in the composition content and of the percentage of each of the constituents in the two studied samples (i.e., large-leaved and narrow-leaved) and within the essential oils of leaves and bracts in both samples were observed. Carvacrol and p-cymene were identified as the main constituents in all essential oils, whereas thymoquinone was found in higher percentage in the essential oils of large-leaved than in narrow-leaved plants. The results obtained from GC-MS analysis were submitted to chemometric analysis, and a phenotypic similarity of the essential oils of narrow-leaved O. dictamnus was observed, whereas the essential oils of large-leaved O. dictamnus showed two separate subgroups © 2005 American Chemical Society

Chemical analysis and antimicrobial studies on three species of Ferulago from Greece

The chemical composition of the essential oils of the flowering parts and of the hexane extracts of the leaves, of three species of the genus Ferulago (Apiaceae) from Greece, i.e., F. thyrsiflora, F. sylvatica and F. nodosa, was analysed by GC and GC-MS. Manoyl oxide isomers and lupanine, were identified in the hexane extracts of F: thyrsiflora. Dillapiole, was identified in all hexane extracts. Ent-3 beta-hydroxy-13-epi-manoyl oxide was identified and isolated from the essential oil of F. thyrsiflora. All these compounds are new reports for the genus Ferulago and are useful chemotaxonomic markers. Chemical data of F. thyrsiflora is presented for the first time. The essential oils and the extracts were investigated for their antimicrobial activity against Gram-positive and Gram-negative microorganisms

Effect of Nitrogen Concentration of the Nutrient Solution on the Volatile Constituents of Leaves of Salvia fruticosa Mill. in Solution Culture

Essential oils from hydroponically cultivated Salvia fruticosa were analyzed by GC-MS techniques. Three different levels of nitrogen (100, 150, and 200 mg/L) were used in the nutrient solution for the cultivation, using the nutrient film technique. A total of 79 compounds were identified, and qualitative and quantitative differences have been observed between the samples collected at full bloom (flowering stage) and at the end of the seed formation stage. 1,8-Cineole, β-caryophyllene, and viridiflorol were the predominant constituents in most cases. 13-epi-Manool was identified by using GC parameters and mass spectrum fragmentation pattern, whereas labd-7,13-dien-15-ol, a labdane type diterpene, was identified for the first time in the genus Salvia, using GC parameters and an authentic sample. The results obtained from GC-MS analyses were submitted to chemometric analysis