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21.
An inoculation procedure was developed to obtain efficient and synchronous infection on detached tomato leaves by Botrytis cinerea. In spray-inoculated leaves incubated at 20 °C, the infection process consisted of three phases: the formation of primary necrotic lesions (until 20 hpi), a quiescent phase (20-72 hpi), and the expansion of a proportion of the primary lesions (from 72 hpi onwards), resulting in full tissue maceration. At 4 °C, the infection progressed slowly but steadily without inducing necrotic responses in the host. The actin and -tubulin genes of B. cinerea were cloned, characterized and used as probes on blots containing RNAs from leaves at various stages of the infection. The genes displayed a similar expression pattern throughout the infection and the hybridization signal reflected the amount of fungal biomass. The actin mRNA accumulated to higher levels than the -tubulin mRNA. Tomato PR protein mRNAs (chitinase, -1,3-glucanase and PR-1) were induced during the infection, albeit with different kinetics and to different levels. At 20 °C, -1,3-glucanase and PR-1 mRNAs were induced more rapidly than chitinase mRNAs. At 4 °C, mRNAs encoding extracellular -1,3-glucanase and intracellular, as well as extracellular chitinase were hardly induced.  相似文献   
22.
The collembological composition of samples from the Central and Western Pyrenees (Northern Spain) was studied. Soils from two biotopes (pine forest and Rhododendron shrub) were studied in Nuria and Vallibierna, using different diversity indices and multivariate analyses. Ten species were found that were endemic to the Iberian Peninsula. Three of these are exclusive to the Pyrenees: Ceratophysella elegans, Hypogastrura dasiensis and Protachorutes pyrenaeus. The greatest diversity was observed in the soils of Rhododendron, above all at Nuria. Collembola were most poorly represented in the pine forest of Vallibierna, where the endemic Hypogastrura meridionalis was the dominant species. Multivariate analyses indicated that the latter species characterizes this pine forest and separates it from all other biotopes studied. The evenness (E) was most pronounced in Nuria, where Folsomia manolachei was the characteristic species.  相似文献   
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24.
Ultrafiltration of a Waste Emulsified Cutting Oil using Organic Membranes   总被引:1,自引:0,他引:1  
Benito  J. M.  Ebel  S.  Gutiérrez  B.  Pazos  C.  Coca  J. 《Water, air, and soil pollution》2001,128(1-2):181-195
The influence of operating conditions on permeate flux was investigated using organic ultrafiltration membranes to treat a synthetic cutting-oil emulsion containing 0.05 to 0.8 wt. % oil. A commercial cutting oil, Alba-Kool, and four organic ultrafiltration membranes, two made of polysulfone (PM10 and PM30) and the other two of regenerated cellulose (YM10 andYM30), with cut-off sizes of 10 000 or 30 000 Dalton, were used.All experiments were performed in a commercially available stirred ultrafiltration cell. Within the range of operating conditions studied, it was found that the highest fluxes wereobtained at the following conditions: crossflow velocity (rotation speed) of 375 rpm, temperature of 40 °C andtransmembrane pressure of 0.1–0.15 MPa. Oil rejections between99 and 99.9% were obtained. Complete membrane regeneration wasachieved with a 2 vol. % aqueous solution of a commercial cleaning agent (Derquim+, Panreac).  相似文献   
25.
J. Salinas  C. Benito 《Euphytica》1983,32(3):783-790
Summary The 6-phosphogluconate dehydrogenase (6-PGD), glucose-6-phosphate dehydrogenase (G-6-PD) and glutamate dehydrogenase (GDH) zymogram phenotypes of wheat, rye and their aneuploid derivates were determined. At least three genes involved in the production of 6-PGD isozymes were located on chromosome arms 4RL, 6RL and 2RL of Imperial rye, King II rye and Dakold rye. Evidence was obtained that at least one gene located on chromosome arm 5RS controls G-6-PD isozyme activities in these varieties of rye and one gene involved in the production of GDH isozymes was located on chromosome arm 2RS of Imperial, King II and Dakold rye. The results indicate that the 6-PGD isozymes exist as dimers and monomers. No possible structure of the G-6-PD and GDH could be determined.  相似文献   
26.
BACKGROUND: Normal response to different types of exercise needs to be established before performance, training level, or exercise intolerance can be assessed. OBJECTIVES: The aim of this research was to describe the hematologic and biochemical changes that dogs undergo during an agility competition. METHODS: Fifteen dogs were subjected to an agility test that covered a distance of 360-400 m with 40 obstacles. Basal venous blood samples were drawn 1 week before the competition, immediately after exercise, and at 5, 15, and 30 minutes of recuperation. A CBC, plasma biochemical profile, and lactate concentration were determined by standard methods using automated analyzers. Serum cortisol concentration was measured by competitive immune-enzyme analysis; insulin was measured by sandwich ELISA. RESULTS: Hematologic response to the agility test consisted of significant increases in RBC count, hemoglobin concentration, and HCT, with no change in total protein concentration. Serum triglyceride concentrations were increased postexercise, with highest values observed at 30 minutes of recuperation. Postexercise lactate concentrations exceeded the anaerobic threshold of 4 mmol/L. Serum lactate dehydrogenase activity was significantly higher after 30 minutes of recuperation. Significant differences were not observed in other analytes. CONCLUSIONS: Our results indicate that agility competitions induce mild to moderate changes in hematologic and biochemical results consistent with splenic contraction, increased lipolysis, and utilization of anaerobic pathways involved in energy resynthesis in muscle.  相似文献   
27.
A spontaneous lung tumor in a 5-year-old goat of the Murciano-Granadina breed is described in this paper. Clinical signs of cachexia and tachypnoea were evident, and a considerable amount of white mucous foamy fluid was discharged from the nostrils when the animal's head was lowered. A lung tumor with the characteristics of bronchioloalveolar carcinoma was detected during histopathologic examination. The tumor cells were positive for surfactant proteins C and B, confirming that alveolar type II cells were the origin of the neoplasia. Tumor samples were tested by polymerase chain reaction, immunoblotting, and immunohistochemistry for the presence of Jaagsiekte sheep retrovirus (JSRV) and enzootic nasal tumor virus (ENTV), another retrovirus very closely related to JSRV, but all tests were negative. Therefore, this is the first reported case of spontaneous bronchioloalveolar carcinoma not related to JSRV or ENTV infection in a goat.  相似文献   
28.

Purpose

Degraded soils, such as those encountered in areas of mine activities, need to be ameliorated by liming to correct soil acidity and by addition of organic inputs to improve soil properties and fertility.

Materials and methods

Non-amended mine soil and soil amended with stabilized sewage sludge were incubated for 45 days. Soil physicochemical and biological indicators were periodically measured along incubation and other enzyme activities at the end of incubation. In improved soils, a study of plant development in 250-g pots was carried out with three vegetal species: tomato, rye grass and ahipa. Germination and mortality rates, biomass production and photosynthetic pigments were measured.

Results and discussion

Soil incubation with sewage sludge slightly increased soil pH and led to an enhancement of soil electrical conductivity, organic carbon and dehydrogenase activity, especially for the higher doses (5 and 10%). However soil respiration was more promoted with the 2% dose, pointing to a possible toxic effect of the sludge. At the end of incubation, physicochemical and biological properties were in general enhanced. Biomass production was improved in tomato and rye grass by sewage sludge addition (more at the 2% dose), whilst ahipa growth was not affected by sewage sludge treatments. Tomato mortality reached 73% with high sludge doses (10%).

Conclusions

According to this set of parameters, amendment with sewage sludge of a limed acid mine soil would be considered as a good strategy for soil amelioration in view of plant establishment and development.  相似文献   
29.
Mediterranean oaks frequently have poor performance in forest restoration projects. We analyzed if nitrogen (N) fertilization during nursery cultivation enhances the outplanting performance of two ecologically distinct oaks, Quercus coccifera L. an evergreen shrub, and Quercus faginea L., a deciduous tree. Additionally, we compared the sufficiency N levels of both oaks and if root growth capacity (RGC) and photosynthesis testing at low air temperature better discriminated among fertilization treatments than testing at mild temperature. Plants were cultivated under five N fertilization rates (0, 30, 75, 150 and 200 mg N plant?1) for one growing season. At the end of the cultivation period several plant material and performance attributes were measured. RGC and photosynthesis were assessed at mild temperature and cool conditions in Q. coccifera, while in Q. faginea these attributes were only analyzed at mild temperature conditions. Q. coccifera seedlings were transplanted into four terraces that imposed increasing drought stress, while Q. faginea seedlings were transplanted into an abandoned wheat cropland. Sufficiency level was higher for the tree (150 mg N plant?1) than for the shrub (75 mg N plant?1) Nitrogen-deprived Q. coccifera plants had higher frost damage than remaining treatments, which did not differ among them. Fertilization in Q. faginea did not affect photosynthesis rate but it delayed leaf senescence and abscission. RGC increased with fertilization in both species. Testing temperature did not change the effect of fertilization on RGC in Q. coccifera. Photosynthesis in cool conditions discriminated N-deprived seedlings from the remaining treatments, but treatments did not differ in photosynthesis at mild temperature. Fertilization enhanced outplanting survival in Q. coccifera, primarily in the terraces imposing stronger drought stress, while fertilization only increased growth in the terraces imposing mild drought stress. Overall, survival and growth was positively related to seedling size at planting in both oaks. Additionally, Q. coccifera survival was also positively related to RGC in the harsh planting conditions. Field growth was positively related to RGC and plant N concentration in both oaks but the relation was weak or nonexistent under harsh conditions in Q. coccifera. We conclude that fertilization in the nursery is an important tool for improving the success of oak plantations in Mediterranean continental sites, and that large and N-rich seedling have greater field performance than small and low tissue N concentration seedlings, especially in harsh field sites.  相似文献   
30.
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