查看更多>>摘要：Dracaena sanderiana Sander ex Mast, (lucky bomboo) is an ornamental plant belonging to the family Agava-ceae. The factors affecting sterilization, explant browning, and shoot proliferation of two cultivars Green and Variegated of D. sanderiana were studied. Micropropagation of D. sanderiana is very important because of the limitations in its conventional propagation by classical vegetative propagation methods which give rise to several bacterial, fungal, viral and mycoplasma diseases. The in vitro condition can overcome these problems. Half-strength Murashige and Skoog's (MS) media supplemented with different concentrations of 6- benzyl-amino-purine (BA mg I"1) and naphthalene acetic acid (NAA) (0.25 and 0.5 mg I"') were used for shoot proliferationand plant regeneration studies. The effect of explant positioning on the culture media, whether horizontal or vertical, was also assessed on proliferation and growth of shoots produced. Explants of the 'Green' cultivar, cultured horizontally on media, were successful in yielding proliferated shoots. The highest mean value (4.8) was recorded on the medium supplemented with 2 mg l'1 BA and 0.25 mg 11 NAA. Explants of the 'Variegated' cultivar, cultured horizontally on media, were also successful in yielding proliferated shoots. The highest mean value (3.66) was recorded on the medium supplemented with 2 mg 11 BA and 0.25 mg I"1 NAA.
查看更多>>摘要：The interaction effect of MS salt strengths and subculturing times were studied in Dracaena sanderiana Sander ex Mast, (lucky bomboo). Stem pieces, each bearing a single node, were cultured horizontally on full, 3/4 and 1/2 strength MS media supplemented with 2 mg 1"' BA and 0.25 mg P1 NAA. Proliferation rate, shoot length, and number of leaves increased when 1/2 strength MS medium was used. The highest shoot length was recorded after the third subculture. Moreover, the greatest number of leaves wasobtained at this stage. The highest mean value for parameters such as rooting percentage, the number of roots, and root length were observed on media supplemented with 2 mg l"1 Indole-3-butyric acid (IBA). Plantlets were subsequently planted in a mixtureof perlite and vermiculite (1:1) under 95% relative humidity and were then transferred to greenhouse conditions. The proposed protocol can be used in commercial mass production of D. sanderiana.
M. Jangali BaygiM. AlizadehM. SharifaniF. Ghaderifar...
5页
查看更多>>摘要：Seed germination is considered an important phenoiogical stage of plant growth during which the viable, non-dormant embryos develop into seedlings under favorable conditions. Currently, various seed priming treatments may be used to enhance germination values (germination percentage, Lag phase, time to reach 50% germination) and breaking dormancy; gibberellins and KNO_3 are applied as common treatments in this regard. In the present study, efficacy of Hydrogen Cyanamid (HCN, Dormex~R) on seed germination of two cultivated pistachio varieties (Abasali, Shahpasand) were studied and the results were compared to ordinary ingredients, namely gibberellic acid (GA_3) and KN03. The extraction of parameters was carried out using four-parameter Hill function.The results reveal that HCN may significantly improve critical parameters involved in pistachio seed germination. In Shahpasand variety, seeds treated with HCN germinated prior to other treatments (150.53 hours after treatment) and achieved 50% germination earlier than other treatments (199.00 hours only). According to the results, utilization of HCN in seed testing experiments may be encouraged.
查看更多>>摘要：The study applies acoustic means for the detection of belowground tuberous roots of sweet potato by developing a novel non-invasive sensing technology based on propagation of frequency-modulated sound through the soil and its detection with acoustic band-pass filtering devices. The presence of tuberous roots hidden in the bed of sandy soil was successfully detected with the proposed acoustic approach, which is still primitive. However, this investigation may induce further studies and developments for belowground sensing and imaging techniques as novel ecological research tools and to support the introduction of vegetables into so-called "plant factories".
查看更多>>摘要：Fusarium is a large genus of filamentous fungi which cause some of the most important diseases in agricultural and horticultural crops. This fungus is considered to be a useful producer of enzymes from an industrial point of view. In the present study, lipase production by Fusarium culmorum SY6 was investigated under solid-state fermentation (SSF). Among the several agronomic wastes, corn cob hulls and tomato pulp supported the highest yield of lipase (170 and 165 U/g of dry substrate, respectively)after five days of incubation. It was determined that pH 9 and 60°C gave optimum enzyme activity. The F. culmorum SY6 strain grown in SSF in a simple medium proved to be a promising microorganism for lipase production.
查看更多>>摘要：Picea abies (L.) Karst. is the most common species cultivated in Italy for sale as Christmas trees. The aim of this study was to identify the best seed provenance to improve plant production. Three Italian provenances - Gran Bosco di Salbertrand, Pezzel e Fochino, and Val di Fiemme - were examined. A part of seeds were sown on benches in a greenhouse after cold stratification, and another part was used for induction of somatic embryogenesis. In the first experiment, two different amounts of organic matter (manure), as components of growing media, were evaluated, while in the second one different levels and combinations of growth regulators in the medium were tested. The seed provenance and composition of the growing medium influenced seed germination and seedling growth. The best performance on both growing media was achieved by the Val di Fiemme provenance, and in general seedling emergence and growth were the most favourable in the growing medium with a lower organic matter amount. Also, the in vitro cultures evidenced differences in the efficiency of somatic embryogenesis among the provenances.
查看更多>>摘要：Carnation {Dianthus caryophyllus L.) flowers are one of the most important cut flowers in the world. The majority of carnation cultivars are sensitive to ethylene which affects the physiological and biochemical postharvest characteristics of these flowers. Applying inhibitors of biosynthesis and action of ethylene is important factor to protect the display quality and extend postharvest life. In order to evaluate the effects of 1-methylcyclopropene (1-MCP) and ethylene on the antioxidant enzyme activity of cut carnation cv. Fortune and subsequently on the extension of vase-life, this experiment was designed as a Completely Randomized Design (CRD) with three replications. Carnation cut flowers were treated with 1-MCP at concentrations of 0,0.5,1 and1.5 ul/1 for 24 h and subsequently exposed to ethylene (1 ul/1) for 16 h. Data were analyzed using MSTAT-C statistical software and means were compared based on Least Significant Differences (LSD) test (p< 0.01). Our results showed that 1-MCP treatment had significant effects on vase life and biochemical characteristics like contents of leaf chlorophyll, petal anthocyanin, petal cell membrane stability and antioxidant enzymes activity such as catalase, peroxidase, and superoxide dismutase. The highest vase life and cell membrane stability were appeared in samples treated with 1.5 ul/I1-MCP which was significantly higher than 0 and 0.5 treatments, although there was no significant difference with 1 ul treatment. The highest chlorophyll and anthocyanin contents were also measured under 1.5 (tl/l 1-MCP which was significantly higher than other treatments. The highest and lowest catalase and peroxidase activity were related to 1 and 0 urt/1 1-MCP, respectively. The highest and lowest superoxide dismutaseactivity was observed in 1.5 and 0 ul/1 1-MCP. In conclusion, application of 1-MCP improved and delayed the onset of senescence symptoms resulted in extending the vase life of cut carnation cv. Fortune.
查看更多>>摘要：The antioxidant content in plant seeds is deemed to affect seed oil protection against auto-oxidation to a large extent, whereas the relationship between a strong antioxidant element such as selenium (Se) and either seed oil accumulation or fatty acids composition has not been investigated so far. The aim of the present work was to assess Se concentrations in seeds and their relationships with oil content and fatty acids composition in: a) ten Allium cepa cultivars, i. e. eight Russian and two Italian; and b) six perennial onion species (A. schoenoprasum,A. obliquum,A. altaicum,A. fistulosum,A. nutans, A. ramndsum). Fatty acids composition of Allium seed oil was determined by gas chromatography method, whereas total and water soluble Se concentration was assessed by microfluorimetric method. The oil content of Allium cepa seeds was 1.7 fold higher (10.7-16.5%) than that recorded in perennial onions (4.0-10.8%) and it was positively correlated with the total Se concentration. Within A. cepa, the seeds of the two Italian cultivars Ramata di Montoro and Rossa di Tropea were characterized by the highest oil content (16.5-16.6%) and oleic acid (25-27%). Linoleic (C18:2) acid was the main fatty acid, followed by oleic (C18:l) and palmitic acids (C16:0)in all cultivars. Among the perennial onion seeds, the highest oil percentage was detected in A. schoenoprasum (10.8%) and the lowest in A. ramndsum (4.0%). Compared to A. cepa cultivars, the perennial onion species showed a similar oil fatty acid composition, with the main acids being C18:2, C18:l and C16:0 in decreasing order, a lower level of C16:0, and enhanced levels of minor SFA, such as C20:0, C22:0 and C24:0. Further differences also included decreased levels of C16:l, 11-trance C18:l and a higher concentration of C22:l. The concentration of water soluble forms of Se in seeds was positively correlated with linoleic acid and with total phenolics. Conversely, oleic acid was negatively correlated with water soluble forms of Se.
查看更多>>摘要：Mycophenolic acid (MPA) is an effective antiviral drug in plants, and its action in modulating the activity of KATP channels is already known in animals. In the present work an electrophysiological study was carried out to investigate MPA effects on plant K+ channels, through the measurement of trans-plasma membrane potential in samples of Vitis vinifera cv. Sangiovese treated with extracellular K+. Tests confirmed that the administration of MPA (in preincubated samples or in those maintained under chemical treatment) can reduce the membrane depolarization induced by K+. However, MPA-induced alteration in membrane potential was sensitive to the KATp channel opener diazoxide, as well to treatments with guanosine. This result confirms the effectiveness of MPA in influencing KATP channel activity as well as inhibiting activity of the inward-rectifier potassium ion channel which could be mediated by guanosine depletion induced by MPA.
查看更多>>摘要：Alternate bearing of olive trees is one of the most troublesome characteristics of this commodity, impacting its economy due to labor distribution, fruit and oil availability, oil mill capacity and marketing. The metabolic changes leading to alteration in fruit production are generally considered of direct genetic nature. In the present review this approach is challenged, showing that all the bi otic-metabolic changes in olive leading to 'on' and 'off' years are the results of initial abiotic effectson the trees. The nature of the metabolic changes induced by the abiotic regional and annual conditions described are, no doubt, genetically controlled but initiated only as a result of adverse environmental abiotic conditions such as seasonal temperatures, water stress, and soil nutrition conditions.
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