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51.
Landscape Ecology - Several case studies investigated the role of ecosystem services in participatory planning processes. However, no systematic study exists that cuts across a large number of...  相似文献   
52.
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   
53.
Root rot caused by the soil-borne pathogen Phytophthora cinnamomi is leading to significant oak tree mortality in rangeland ecosystems in south western Spain. Susceptibility to P. cinnamomi infections of Q. ilex seedlings with a standard nutrition, deficient in K+, and deficient in Ca2+, was tested. Oaks deficient in K+ showed high values in Ca2+ content and were tolerant to the disease. Nutritional deficiency in Ca2+, however, did not lead to a higher K+ level in plants and induced poorer root development. In addition, K+ plant content does not appear to have any effect on pathogen tolerance. Based on these results, we conclude that satisfactory calcium nutrition may confer Holm oaks with a greater tolerance to root disease caused by P. cinnamomi. For this reason, limestone supplements are recommended as a measure against root rot caused by P. cinnamomi in rangelands in southern Spain, as a good option for control of oak root disease.  相似文献   
54.
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   
55.
The activity of 8-prenylapigenin (8-PA) and its 3'-methoxylated analogue isocannflavin B (IsoB) was investigated in estrogen-dependent T47-D and estrogen-independent MDA-MB-231 human breast cancer cell lines. 8-PA showed a biphasic effect on T47-D cell proliferation, while no significant effect was observed on MDA-MB-231 cells. Conversely, IsoB exhibited only an inhibitory effect on T47-D cell proliferation, accompanied by the appearance of an intense intracytoplasmic vacuolization of autophagic origin. Moreover, biochemical analysis showed that IsoB reduced Akt phosphorylation and p21Cip1 expression in T47-D cells. These data show that the prenylflavone moiety is a versatile platform for the induction and modulation of bioactivity.  相似文献   
56.
Photoinhibition of photosynthesis and photosynthetic recovery were studied in detached needles of cypress (Cupressus sempervirens L.) Clones 52 and 30 under controlled conditions of high irradiation (about 1900 micromol m(-2) s(-1) for 60 min; HL treatment), followed by 60 min in darkness. The degree of photoinhibition was determined based on the ratio of variable to maximum chlorophyll fluorescence (Fv/Fm), which is a measure of the potential efficiency of photosystem II (PSII), and on electron transport measurements. The Fv/Fm ratio declined in needles of both clones in response to the HL treatment. Minimal fluorescence (Fo) increased in HL-treated needles of both clones. The HL treatment decreased rates of whole-chain and PSII activity of isolated thylakoids more in Clone 52 than in Clone 30. In needles of both clones, PSI activity was less sensitive to photoinhibition than PSII activity. In the subsequent 60-min dark incubation, fast recovery was observed in needles of both clones, with PSII efficiencies reaching similar values to those in non-photoinhibited needles. The artificial exogenous electron donors diphenyl carbazide (DPC), hydroxylamine (NH2OH) and manganese chloride (MnCl2) failed to restore the HL-induced loss of PSII activity in needles of Clone 30, whereas DPC and NH2OH significantly restored PSII activity in photoinhibited needles of Clone 52. Quantification of the PSII reaction center protein D1 and the 33-kDa protein of the water-splitting complex following HL treatment of needles revealed pronounced differences between Clone 52 and Clone 30. The large decrease in PSII activity in HL-treated needles was caused by the marked loss of D1 protein and 33-kDa protein in Clone 30 and Clone 52, respectively.  相似文献   
57.

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   
58.
Hydrolysates obtained by autohydrolysis-posthydrolysis of corncobs were detoxified with charcoal, concentrated, supplemented with nutrients, and fermented with Debaryomyces hansenii. After biomass removal, the fermented media contained 0.1137 kg of nonvolatile components (NVC)/kg of liquor, which corresponded mainly to xylitol (0.6249 kg/kg of NVC) but also to minor amounts of inorganic components (measured as ashes), proteins, nonfermented sugars (xylose and arabinose), uronic acids, arabitol, and other nonvolatile components (ONVC). The media were subjected to further processing (sequential stages of adsorption, concentration, ethanol precipitation, concentration, and crystallization) to obtain food-grade xylitol. Adsorption experiments were carried out at various solid-to-liquor ratios. Under selected conditions (1 kg of charcoal/15 kg of liquors), the xylitol content increased to 0.6873 kg/kg of NVC, and almost total decoloration was achieved. The resulting liquor was concentrated by evaporation to increase its NVC content to 0.4032 kg/kg of liquor (corresponding to a xylitol concentration of 0.280 kg/kg of liquor), and ethanol was added to precipitate a part of the NVC (mainly proteins, but also uronic acids, ashes, and other nonvolatile compounds). Refined liquors (containing 0.7303 kg of xylitol/kg of NVC) were concentrated again, and ethanol was added (to reach 40-60% volume of the stream) to allow crystallization at -10 or -5 degrees C. Under selected conditions, 43.7% of xylitol contained in the initial fermentation broth was recovered in well-formed, homogeneous crystals, in which xylitol accounted for 98.9% of the total oven-dry weight. Material balances are presented for the whole processing scheme considered in this work.  相似文献   
59.
60.
Paolo Ranalli 《Euphytica》1996,87(2):127-132
Summary The effect of a recurrent selection procedure for improving seed yield per plant was evaluated in common bean. Progress was registered after three cycles of recurrent selection with S2 progeny evaluation performed on the grain yield/plant. Gain from selection was estimated by field testing 45 random S2 lines from each of the C0, C1 and C2 populations. Response to selection for seed yield/plant was 6 g from C0 to C1 and 4.4 g from C1 to C2. The seed yield improvement was due principally to an increase in pods/plant; little contribution was provided by the 1000-seed weight and seeds/pod traits. Broad-sense heritability and genotypic variance for grain yield remained high in all cycles which suggests further gain from additional selection cycles. Grain yield/plant is significantly correlated to pods/plant and seeds/pod traits in all cycles, indicating that plants with favourable combinations of these traits could be identified. The proposed recurrent selection procedure appears to be effective in improving the population and extracting superior genotypes for varietal development.  相似文献   
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