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991.
This list gives a first account on the nomenclature of common parasitic fungi on bulbs as used in official publications of the Netherlands Society of Plant Pathology and the Netherlands Ministry of Agriculture and Fisheries. The selected names include one new species,Colletotrichum lilii Plakidas ex Boerema & Hamers, and four new combinations:Botrytis convallariae (Kleb.) Ond?ej ex Boerema & Hamers,Puccinia sessilis Schneid. ex Schröt. f. sp.convallariae-digraphidis (Kleb.) Boerema & Hamers and f. sp.smilacearum-digraphidis (Kleb.) Boerema & Hamers, andSclerotium rolfsii var.delphinii (Welch) Boerema & Hamers.  相似文献   
992.

Context

Socio-ecological landscapes typically characterized by non-linear dynamics in space and time are difficult to be analyzed using standard quantitative methods, due to multiple processes interacting on different spatial and temporal scales. This poses a challenge to the identification of appropriate approaches for analyzing time series that can evaluate system properties of landscape dynamics in the face of disturbances, such as uncontrolled fires.

Objective

The purpose is the application of non-linear methods such as recurrence quantification analysis (RQA) to landscape ecology. The examples concern the time series of burnt and unburnt Mediterranean rangelands, to highlight potential and limits of RQA.

Methods

We used RQA together with joint recurrence analysis (JRA) to compare the evolutionary behavior of different land uses.

Results

Time series of forests and grasslands in rangelands present both periodic and chaotic components with a rather similar behavior after the fire and clear transitions from less to more regular/predictable dynamics/succession. Results highlight the impacts of fire, the recovery capacity of land covers to pre-burnt levels, and the decay of synchronization towards the previous regime associated with vegetation secondary succession consistent with early successional species.

Conclusions

RQA and JRA with their set of indices (recurrence rate: RR, laminarity: LAM, determinism: DET, and divergence: DIV) can represent new sensitive measures that may monitor the adaptive capacity and the resilience of landscapes. However, future applications are needed to standardize the analysis by strengthening the accuracy of this approach in describing the ongoing transformations of natural and man-managed landscapes.
  相似文献   
993.
Alkaline stress is caused by accumulation of alkaline salts (such as NaHCO3 and Na2CO3) in the soil. This problem, common in arid and semiarid areas of Spain, results from intensive agriculture, the use of hard water, and cultivation in areas of calcareous rock. The present study examines plant metabolic responses against this stress in Brassica oleracea L. cv. Bronco in order to better understand the systems of resistance that could promote plant growth in alkaline soils, and indicates the most relevant biomarkers of alkalinity toxicity. Alkaline stress causes a sharp reduction in biomass, an accumulation of Na+, and a nutritional deficiency. With this debilitated photosynthetic capacity and the antioxidant activity, superoxide dismutase (SOD) sharply decreases and O2.- accumulates, resulting in two of the main causes of stress. Therefore the mechanisms of uptake and compartmentalisation of nutrients and detoxification of O2.- systems should be strengthened in order to remedy alkaline stress. In this work, the authors conclude that Na, P, K, Ca, Mg, and Mn ions are the best indicators of alkaline stress, due to their strong correlation with reduced leaf biomass reduction and photosynthetic pigments, together with the greater accumulation of proline and certain antioxidant enzymes such as SOD.  相似文献   
994.
ABSTRACT

Coffee trees show the fluctuation in production related to biannual phenological development. We aimed to quantify the berry distribution over the vertical profile and relate the chemical composition of coffee beans during few subsequent harvests in each of two production years (PY). The analyzed coffee productions followed severe pruning of plants grown in different planting designs. In the second PY, coffee plants loaded roughly fourfold more berries than the first PY. In the first PY, berry distribution in zones of plagiotropic axes that passed all physiological phases was characterized by random maturation over three harvests, while in the second PY, berry maturation over the orthotropic and plagiotropic axes differed between two harvests, suggesting higher impact of local light microclimate and, consequently, local source–sink relations. Proteins, sucrose, and lipids were the most sensitive studied chemical components when modifications in coffee beans composition were analyzed, considering the impacts of PY, harvest time, planting design, and berry position. Sucrose content increased in latter harvests, indicating better berry maturation compared to the first harvest in both PY. Protein and caffeine contents increased and lipids decreased in higher density and low plant layer during the second PY, suggesting that deposition of those components was modified by self-shading and maturation time related to the berry position over the plant profile.  相似文献   
995.
Tropical Animal Health and Production - The objective of this study was to evaluate intake, digestibility, microbial protein production, and nitrogen balance of lambs fed with different dehydrated...  相似文献   
996.
Tropical Animal Health and Production - The objective of this study was to evaluate the effect of the substitution of Tifton 85 hay (Cynodon spp.) with spineless cactus (Nopalea cochenillifera) on...  相似文献   
997.
In this study we have investigated the prevalence of aelurostrongylosis, one of the most common feline pulmonary parasitic diseases, in cats from the north-west region of Portugal. For this purpose, 97 faecal samples were collected from cats at risk of being infected by Aelurostrongylus abstrusus in an animal shelter and in a municipal facility. Using the Baermann-Wetzel coprological technique, faecal shedding of first stage larvae (L1) was detected in 17.4% of the cats. Based on this result, it can be concluded that this lungworm infection seems to be common among feral cats in the north-west region of Portugal, in spite of the fact that clinical aelurostrongylosis is not frequently diagnosed by feline practitioners in the area. This parasitic disease should be included in the differential diagnosis of cats presenting with coughing or dyspnoea, and it also should be extended to asymptomatic animals with pulmonary nodules detected by image diagnosis.  相似文献   
998.
Glutathione is an important intracellular tripeptide with multiple functions. Abnormal glutathione metabolism is thought to play an important role in various diseases of cats. However, no data regarding concentration of plasma glutathione are available for domestic cats. This study discusses the development of a rapid, simple high pressure liquid chromatography method for measurement of reduced glutathione (GSH), oxidized glutathione (GSSH) and total glutathione (GSHt) in plasma, for the purpose of establishing baseline data for future studies. The mean concentrations of GSH, GSSH and GSHt were 4.51+/-1 microM; 19.44+/-3.79 microM (expressed as GSH equivalent) and 23.59+/-3.89 microM, respectively. This is the first report of plasma glutathione concentrations in this species.  相似文献   
999.
The objective of this study was to evaluate the levels of reactive oxygen species (ROS) and glutathione (GSH) in oocytes from follicles of different diameters and their relevance in the in vitro production of embryos (IVPE). Bovine ovaries were aspirated according to the diameter of the follicle [2–8 (general), 4–8 (large), and 2 < 4 mm (small)]. The oocytes were evaluated for levels of ROS, GSH, in vitro maturation, and IVPE. Higher levels of ROS and GSH were observed (p < 0.05) in oocytes of the large group (85.6 ± 7.2 and 140.0 ± 9.6) followed by those in the general (81.1 ± 10.5 and 134.3 ± 7.8) and small (73.5 ± 10.1 and 125.0 ± 10.6) groups. However, the proportion of ROS/GSH did not differ (p > 0.05) between the general, large, and small groups. The maturation was higher (p < 0.05) in the large group (87.8 ± 3.0%) than in the small group (72.2 ± 5.8%), but both were similar (p > 0.05) to that in the general group (82.2 ± 2.5%), whereas the IVPE of the large group (57.3 ± 3.0%) was higher (p < 0.05) than those in the general (44.7 ± 4.4%) and small (34.0 ± 4.0%) groups. We report that oocytes from large follicles are more competent for IVPE, whereas higher levels of ROS and GSH appear to be correlated with oocyte competence, as long as oxidative homeostasis is retained.  相似文献   
1000.
The aim of the study was to evaluate semen quality in the two most popular colour morphs of the Arctic fox Alopex lagopus L., blue and white, based on ejaculate parameters, acrosin activity and analysis of sperm morphology. The research material consisted of ejaculates collected once by manual stimulation from 20 one‐year‐old male Arctic foxes (10 individuals of the blue morph and 10 of the white morph). Ejaculates were evaluated in terms of volume, sperm concentration, total number of spermatozoa and the percentage of spermatozoa with major and minor defects. The study revealed that male blue Arctic foxes produce ejaculates with much higher concentration (148.75 × 106/ml) and total number of spermatozoa (98.16 × 106) compared to white Arctic foxes (42.88 × 106/ml and 35.2 × 106 respectively). The level of acrosin activity from white foxes seemed to be higher compared to blue foxes but the difference was not statistically confirmed. Semen from Arctic foxes is characterized by high inter‐individual variability in sperm morphology. The frequency of morphological changes in sperm from Arctic foxes does not significantly depend on ejaculate volume, sperm concentration or the total number of spermatozoa in the ejaculate, but is associated with acrosin activity.  相似文献   
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