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61.
Diversity of the calabash tree (<Emphasis Type="Italic">Crescentia cujete</Emphasis> L.) in Colombia
Johanna Arango-Ulloa Adriana Bohorquez Myriam C. Duque Brigitte L. Maass 《Agroforestry Systems》2009,76(3):543-553
Germplasm of the calabash tree (Crescentia cujete L.) was collected in five major regions of Colombia, i.e. the Andes, Caribbean, Amazon, Orinoco, and Pacific regions. Collecting
this multipurpose tree was guided by the indigenous knowledge of farmers and artisans in each region. Large variation in fruit
shapes and sizes was found, of which some forms were typical for certain regions. Overall 56 accessions were collected and
roughly classified into 22 types by eight fruit shapes and eight sizes. Molecular markers (Amplified fragment length polymorphisms)
were applied to leaf tip tissue originating from vegetatively propagated plants in order to assess the diversity available
in the germplasm collected as well as to detect patterns of geographical or morphological similarity. One accession each of
C. alata H.B.&K. and C. amazonica Ducke were used as outgroups. Overall, genetic diversity was high (mean Nei and Li’s coefficient of 0.43). No relations could
be established between either geographical provenance or fruit morphology and patterns of genetic diversity. Concerning the
outgroups, the C. amazonica accession appeared to be a distinct species. The C. alata accession, however, did not seem to be sufficiently distinct from C. cujete to merit species status. The latter material may in fact be a hybrid or serve to challenge the validity of interspecific
organization of the genus Crescentia.
相似文献
Brigitte L. Maass (Corresponding author)Email: |
62.
Stem water-soluble carbohydrates (WSCs) are important plant traits influencing grain yields in wheat. However, the traits regulating WSCs storage, particularly under different nitrogen (N) levels are poorly addressed. This study investigated 35 morpho-physiological traits associated with the variation in WSC concentration (WSCc) in the main stem of eight wheat genotypes including two primitive genotypes under three N levels (0, 100, and 200 kg N ha−1). 28 traits were significantly, positively or negatively, correlated with the WSCc in all N levels, and 22 of them were consistent across N levels. Majority of the traits were positively correlated with WSCc suggesting that multiple traits regulate WSCc in wheat plants. However, few traits such as root:shoot ratio (RSR), stem nitrogen (SN), leaf nitrogen (LN), nitrogen per unit leaf area (NLA), total vegetative mass (VMASS), cellulose (CL), and hemicellulose (HC), were negatively correlated with WSCc. This suggests that plant N concentration was an important selective force driving WSCc in wheat. Indeed, a percent increase in leaf N concentration resulted in 28% lower WSCc. Direct selection estimated that higher VMASS, flag-leaf width (FLW), but lower RSR was adaptive and resulted in higher WSCc in low N level. In contrast, lower VMASS and FLW were adaptive and resulted in higher WSCc in high N level. Higher cellulose and hemicellulose were associated with lower WSCc suggesting that a reduced carbon flux to stem structural compounds may improve WSCc in wheat plants. Together, these results demonstrate that a specific suit of trait changes that evolve under N-specific selection increase main stem WSCc but the adaptive value of these changes varies among traits and N levels. 相似文献
63.
Göran Bergkvist Maria Stenberg Johanna Wetterlind Birgitta Båth Sara Elfstrand 《Field Crops Research》2011
Four two-year field trials, arranged in randomised split-plots, were carried out in southern Sweden with the aim of determining whether reduced N fertiliser dose in winter wheat production with spring under-sown clover cover crops, with or without perennial ryegrass in the seed mixture, would increase the clover biomass and hence the benefits of the cover crops in terms of the effect on the wheat crop, on a subsequent barley crop and on the risk of N leaching. Four doses of nitrogen (0, 60, 120 or 180 kg N ha−1) constituted the main plots and six cover crop treatments the sub-plots. The cover crop treatments were red clover (Trifolium pratense L.), white clover (Trifolium repens L.) and perennial ryegrass (Lolium perenne L.) in pure stands and in mixtures. The winter wheat (Triticum aestivum L.) was harvested in August and the cover crops were ploughed under in November. The risk of N leaching was assessed in November by measuring the content of mineral N in the soil profile (0–30, 30–90 cm). In the following year, the residual effects of the cover crops were investigated in spring barley (Hordeum distichon L.) without additional N. Under-sowing of cover crops did not influence wheat yield, while reduced N fertiliser dose decreased yield and increased the clover content of the cover crops. When N was applied, the mixed cover crops were as effective in depleting soil mineral nitrogen as a pure ryegrass cover crop, while pure clover was less efficient. The clover content at wheat harvest as well as the amount of N incorporated with the cover crops had a positive correlation with barley yield. Spring barley in the unfertilised treatments yielded, on average, 1.9–2.4 Mg DM ha−1 more in treatments with clover cover crops than in the treatment without cover crops. However, this positive effect decreased as the N dose to the preceding wheat crop increased, particularly when the clover was mixed with grass. 相似文献
64.
Mini-plug transplant seedlings of Norway spruce have been cultivated in closed growth systems, so-called plant factories, for few years. The aim of the experiment was to define a short-day treatment (SD) that harden seedlings to sustain 3 months of cold storage, but does not have adverse effects on growth, morphology, and vitality. The seedlings were subjected to one of the following treatments: (1) 12?h photoperiod + 3 weeks duration; (2) 8?h photoperiod + 3?wk duration; (3) 12?h photoperiod + 5?wk duration; and (4) 8?h photoperiod + 5?wk SD. All the SD treatments yielded healthy seedlings that grew well after the cold storage. The frost hardiness of the seedlings improved when the photoperiod was reduced from 12 to 8?h, and when the SD duration was increased from 3 weeks to 5 weeks, but reducing the photoperiod from 12?h to 8?h caused growth reductions. The root and shoot regrowth after cold storage was highest in seedlings that had received 12?h photoperiod and 5?wk duration. However, 12?h photoperiod and 3?wk duration may be an adequate practice for nurseries that treat multiple crops in their SD facilities. 相似文献
65.
David Castro Johanna Urzúa Mariano Rodriguez-Malebran Claudio Inostroza-Blancheteau 《Journal of Sustainable Forestry》2017,36(8):764-786
Woody leguminous species are valuable crops because of their nutritional, economic, and ecological characteristics. Such crops have aided in the recovery of marginal lands for agricultural development due to their ability to fix nitrogen, control erosion, and act as a refuge for other species, in addition to their capacity to improve soil mineral composition and microbial biodiversity. Nevertheless, some leguminous trees are recognized to be one of the worst invasive species that affect negatively biodiversity and the entire ecosystem balance. In this study, we review new global uses for some woody leguminous crops, highlighting new nutraceutical and pharmacological properties, their uses as bioenergy sources, and their ecological uses for bioremediation opening new possibilities of management. We aim to bring knowledge on the multiple benefits that these woody plants continue to provide to humans from economic, social, and environmental standpoints. 相似文献
66.
Jaana Laurila Asko Hannukkala Johanna Nykyri Miia Pasanen Valérie Hélias Linda Garlant Minna Pirhonen 《European journal of plant pathology / European Foundation for Plant Pathology》2010,126(2):249-262
Biochemical characterisation of Dickeya strains isolated from potato plants and river water samples in Finland showed that the majority of the strains were biovar 3. They thus resembled the strains recently isolated from potato in the Netherlands, Poland and Israel and form a new clade within the Dickeya genus. About half of the Finnish isolates resembling strains within this new clade were virulent and caused wilting, necrotic lesions and rotting of leaves and stems. Similar symptoms were caused by D. dianthicola strains isolated from one potato sample and from several river water samples. Frequently, the rotting caused by the Dickeya strains was visible in the upper parts of the stem, while the stem base was necrotic from the pith but hard and green on the outside, resulting in symptoms quite different from the blackleg caused by Pectobacterium atrosepticum. The presence of Dickeya in the symptomatic plants in the field assay was verified with a conventional PCR and with a real-time PCR test developed for the purpose. The virulent Dickeya strains reduced the yield of individual plants by up to 50% and caused rotting of the daughter tubers in the field and in storage. Management of Dickeya spp. in the potato production chain requires awareness of the symptoms and extensive knowledge about the epidemiology of the disease. 相似文献
67.
Georg Schirrmacher Thomas Skurk Hans Hauner Johanna Graßmann 《Plant foods for human nutrition (Dordrecht, Netherlands)》2010,65(1):71-76
Daily consumption of fruits and vegetables is frequently recommended to prevent several diseases. This health-promoting effect
is considered to be in part due to the antioxidant content of fruits and vegetables and their ability to decrease oxidative
stress. To investigate whether the ingestion of preparations from spinach or perilla, two carotenoid-rich leafy vegetables,
is followed by an increase in carotenoid concentration and/or affects parameters of oxidative stress in human blood plasma.
12 healthy volunteers ingested a perilla- or spinach preparation for 10 days (5 mg lutein/d). We quantified antioxidant levels
in plasma, kinetics of lipid peroxidation, MDA concentration, and total antioxidative capacity of plasma. We observed a significant
increase in lutein content and a moderate increase (n.s.) in β-carotene content in human blood plasma after consumption of
spinach or perilla. The markers of lipid peroxidation tended to decrease, but no influence on antioxidative capacity of plasma
could be detected. The high lutein content of perilla caused a more pronounced increase of lutein compared to spinach. Both
vegetables seem to be able to influence lipid peroxidation in a beneficial manner. 相似文献
68.
M Johanna Kaartinen Daniel S J Pang Sophie G Cuvelliez 《Veterinary anaesthesia and analgesia》2010,37(2):136-143
Case 1 A two‐year old, 462 kg Standard bred horse was anesthetized for arthroscopy and castration. During anesthesia, hyperemia of the mucosal membranes and urticaria were noticed. During 5 hours of anesthesia subcutaneous edema of the eyelids and neck region developed. In the recovery box, the orotracheal (OT) tube was left in situ and secured in place with tape. Following initial attempts to stand, the horse became highly agitated and signs consistent with pulmonary edema developed subsequently. Arterial hypoxemia (PaO2: 3.7 kPa [28 mmHg]) and hypocapnia (PaCO2: 3.1 kPa [23 mmHg]) were confirmed. Oxygen and furosemide were administered. The horse was assisted to standing with a sling. Therapy continued with bilateral intra‐nasal oxygen insufflation. Ancillary medical therapy included flunixin meglumine, penicillin, gentamycin and dimethylsulfoxide. Following 7 hours of treatment the arterial oxygen tensions began to increase towards normal values. Case 2 An 11‐year old, 528 kg Paint horse was anesthetized for surgery of a submandibular mass. The 4‐hour anesthetic period was unremarkable. The OT tube was left in situ for the recovery. During recovery, the horse was slightly agitated and stood after three attempts. Clinical signs consistent with pulmonary edema and arterial hypoxemia (PaO2: 5 kPa [37.5 mmHg]) subsequently developed following extubation. Respiratory signs resolved with medical therapy, including unilateral nasal oxygen insufflation, furosemide, flunixin meglumine and dimethylsulfoxide. The diagnosis of pulmonary edema in these horses was made by clinical signs and arterial blood‐gas analysis. While pulmonary radiographs were not taken to confirm the diagnosis, the clinical signs following anesthesia support the diagnosis in both cases. The etiology of pulmonary edema was most likely multifactorial. 相似文献
69.
Antti Kilpeläinen Johanna Routa Heli Peltola Ane Zubizarreta Gerendiain Pertti Pulkkinen Seppo Kellomäki 《Forest Ecology and Management》2010
The effects of genetic entry and competition on the above ground dry biomass production (i.e. stem wood, needles, branches and harvest index) was studied in 20 Norway spruce (Picea abies (L.) Karst.) clones grown in southern Finland. Furthermore, the measured above ground biomass components were compared against the corresponding estimations based on biomass models developed previously. The clones included both Finnish and Russian clones, as well as provenance-hybrids clones. Differences existed between clones in stem dry mass production, but not in harvest index or in crown dry mass. However, the competition caused by neighboring trees also significantly affected above ground dry biomass, as well as the biomass of crown and stem separately. Differences in competition between the clones could not be found. Unlike the dry mass of branches, the dry mass of needles and stem could be estimated well for individual sample trees with the available biomass models. Moreover, the clone with the largest above ground dry biomass production had nearly doubled production, on average, than the average over all clones. Thus, some of the clones showed especially high potential for biomass recovery in energy wood thinning. 相似文献
70.
Ma H Forssell P Kylli P Lampi AM Buchert J Boer H Partanen R 《Journal of agricultural and food chemistry》2012,60(24):6223-6229
Sodium caseinate was modified by transglutaminase catalyzed cross-linking reaction prior to the emulsification process in order to study the effect of cross-linking on the oxidative stability of protein stabilized emulsions. The extent of the cross-linking catalyzed by different dosages of transglutaminase was investigated by following the ammonia production during the reaction and using SDS-PAGE gel. O/W emulsions prepared with the cross-linked and non-cross-linked sodium caseinates were stored for 30 days under the same conditions. Peroxide value measurement, oxygen consumption measurement, and headspace gas chromatography analysis were used to study the oxidative stability of the emulsions. The emulsion made of the cross-linked sodium caseinate showed an improved oxidative stability with reduced formation of fatty acid hydroperoxides and volatiles and a longer period of low rate oxygen consumption. The improving effect of transglutaminase catalyzed cross-linking could be most likely attributed to the enhanced physical stability of the interfacial protein layer against competitive adsorption by oil oxidation products. 相似文献