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41.
Summary Potato seed tubers may suffer from premature sprouting during storage, thus limiting their suitability for cultivation. Commonly used sprout suppressant treatments negatively affect but viability and therefore a reliable method to inhibit bud development must still be found for seed tubers. The monoterpene carvone ((S)-(+)-carvone) was tested in small scale experiments. The vapour of this compound fully inhibited bud growth of tubers cv. Monalisa stored at 23°C without affecting bud viability throughout 6 months of treatment. The most effective range of carvone vapour concentrations was between 0.34 and 1.06 μmol mol−1. With these qualities we can expect carvone to become a suitable sprout suppressant for seed tubers.  相似文献   
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The red palm weevil (RPW), Rhynchophorus ferrugineus Olivier (Coleoptera, Curculionidae), is one of the most severe pests of ornamental palm species in urban areas of Mediterranean countries. Aiming to discover inhibitory semiochemicals for RPW population management in urban environments, we conducted electroantennographic (EAG) screenings of 17 commercially available synthetic compounds, representing three groups of plant volatiles (isoprenoids, phenyl propanoid derivatives and fatty acid derivatives) known for their repellent effects toward insects. These tests were followed by trap-based screenings of EAG-active menthone, α-pinene and methyl salicylate, singly and in combination, under urban conditions. In EAG bioassays, RPW antennae of both sexes showed positive dose-dependent responses to 13 of the 17 synthetic chemicals with significant differences among them. In field trapping experiments, conducted in the city of Palermo, Italy, from weeks 31 to 38 in 2010 and 2011, α-pinene, tested singly or in combination with methyl salicylate (2010) or menthone (2011), reduced trap catches by about 30% to 40%. Methyl salicylate and menthone alone were inactive. In conclusion, RPW is significantly affected by α-pinene. This isoprenoid is a promising disruptant for semiochemical-based management of this pest. In addition, identification of a large number of EAG-active chemicals could serve as a database for future design of active repellents or attractants of RPW adults.  相似文献   
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A study was conducted to evaluate a non-destructive method able to predict Magness–Taylor (MT) penetrometric firmness of blood oranges, potentially applicable for on-line selection. The method consisted of multivariate modelling of non-destructive penetrometric measurements performed on intact oranges with a 11.3 mm diameter probe by digital dynamometric equipment. The tests were carried out on 366 blood oranges (Citrus sinensis (L.) Osbeck cv. Tarocco); 60 were used as a control group to verify the non-destructive nature of the tests. Four test factors were used on the fruit: two different levels of non-destructive deformation (1 and 3 mm), at two different deformation speeds (5 and 30 mm s?1). In order to obtain the reference parameter (MT firmness), a destructive penetrometric test followed each non-destructive deformation on the same fruit (deformation of 20 mm at 1 mm s?1). The force–deformation curves of the non-destructive tests were elaborated to calculate different texture parameters (max force, elasticity, work). These parameters with raw curve data (force values for constant deformation steps) were used, after autoscaling pre-processing, as X-block datasets in supervised multivariate modelling (partial least squares) to predict MT firmness values. Among the test factors used, the 30 mm s?1 speed and 3 mm deformation provided the best overall prediction of MT firmness. This comprised an r value of 0.76 and standard error of prevision (SEP) of 2.99 N for a MT firmness mean value of 35.65 N (8.4%). The time needed to apply the selected deformation may lead to a sorting speed of about 10 fruit per second, representing an acceptable value for commercial application.  相似文献   
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Guarrera PM 《Fitoterapia》2003,74(6):515-544
A series of research projects on wild plants used in Central Italy (Marche, Latium and Abruzzo) as food medicine and for minor nourishment was carried out in the years 1979-2000. This study reports a summary of the data personally collected in the field. Minor nourishment appears to be still consistently utilised: wild plants are consumed preferably in salads, boiled or in omelettes. Some therapeutic properties are attributed by people to the alimentary plants, often documented by the scientific literature. In this study, folk alimentary and/or therapeutic food uses of 126 entities distributed among 39 families are described. Particular folk uses concerning cultivated plants are also reported. In this paper, for the first time pharmacobotanical properties are systematically emphasised for the folk food species of Central Italy. References to analogous alimentary uses in Central Italy are documented. Comparisons among different food traditions are also discussed.  相似文献   
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Traditional phytotherapy in Central Italy (Marche, Abruzzo, and Latium)   总被引:2,自引:0,他引:2  
In this study, the more significant results of extensive ethnopharmacobotanical research carried out by the author in the years 1977-2000 in 175 localities of three regions of Central Italy (Marche, Abruzzo, and Latium) have been reported and compared. The usages of 80 species belonging to 36 families are described, of which 71 were used in human therapy and 29 in veterinary medicine. Uses are suited with the number of localities in which they have been mentioned. Among the wild plant mainly still used, Malva sylvestris, Urtica dioica, and Sambucus nigra are particularly highly considered, while major uses of plants concern these plants in addition to Allium sativum, Rubus ulmifolius, Parietaria diffusa, Cynodon dactylon, and Ficus carica. Unusual phytotherapic uses concern Brassica oleracea, Taraxacum officinale (warts), Ruscus aculeatus, S. nigra (chilblains), Allium cepa (chilblains; to remove thorns and splinters), Juglans regia, R. ulmifolius (burns), and Euphorbia paralias (bites of weevers). Among new uses with only one quotation, we remember Cirsium arvense (intestinal disturbances), Centaurea bracteata (cough), Lupinus albus (calluses), Melittis melissophyllum (eye inflammations, antispasmodic), and Artemisia absinthium (tendon inflammations), while among plants employed in various regions with interesting less-known properties, there are C. arvense (emergency haemostatic), P. diffusa (insect bites), and Scrophularia canina (antiseptic and cicatrizing agent for wounds in bovines and sheep).  相似文献   
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Key message

Comparisons between compression and opposite wood formation in prostrating Pinus mugo indicate that the secondary meristem can produce more tracheids with thicker walls by also increasing the number of contemporaneously differentiating cells, rather than only increasing the duration or the rate of cell formation.

Context

Although cambium tissues within a stem experience the same climatic conditions, the resulting wood structure and properties can strongly differ. Assessing how meristem differently regulates wood formation to achieve different anatomical properties can help understanding the mechanisms of response and their plasticity.

Aims

We monitored the formation of compression (CW) and opposite (OW) wood within the same stems to understand whether achieved differences in wood structure are caused by modifications in the process of cell formation.

Methods

We collected weekly microcores of compression and opposite wood from the curved stem of ten treeline prostrating mountain pines (Pinus mugo Turra ssp. mugo) at the Majella massif in Central Italy.

Results

Results indicate that cambium formed approximately 1.5 times more cells in CW than OW, despite that CW cell differentiation only extended 2 weeks longer and the residence time of CW cells in the wall-thickening phase was only 20% longer. Differences in their formation were thus mainly related to both the rates and the width of the enlarging and wall-thickening zones (i.e., the number of cells simultaneously under differentiation) and less to duration of cell formation.

Conclusion

We conclude that to achieve such a different wood structures, the efficiency of the secondary meristem, in addition of altered rate of cell division and differentiation, can also modify the width of the developing zones. Thus, deciphering what rules this width is important to link environmental conditions with productivity.
  相似文献   
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