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Seed of Adonis microcarpa (pheasant's eye) fed at 5.6 g/kg of the diet induced virtually total feed refusal within 3 d in growing and finishing pigs. It also caused vomiting, rapid and shallow breathing and death in a minority. These effects were probably caused by cardiac glycosides whose structure and effects closely resemble those of digoxin. Feed intake and growth recovered within 2 weeks of removal of the seed. 相似文献
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Maria Concepción Lora-Vilchis Esperanza Ruiz-Velasco-Cruz Teodoro Reynoso-Granados Domenico Voltolina 《Journal of the World Aquaculture Society》2004,35(2):232-236
–Juvenile pen shells Atrina maura were fed for 21 d with equal daily rations, equivalent to 6.5% of their live weight, of monoalgal cultures of Tetraselmis suecica, Isochrysis galbana, Chaetoceros muelleri, Chaetoceros calcitrans , and Thalassiosira pseudonana. Pen shell survival was 100% in all cases. All microalgae diets produced shell growth, and live and ash-free dry weight increases. However, the two Chaetoceros strains gave significantly better results, with shell height increases of 4.7 to 2.9 mm, live weight gains of 0.5 to 0.3 g, and final ash-free dry weights of 0.16 to 0.14 g after 3 wk. These results are not related to the algae gross biochemical composition, suggesting that other factors are involved in their nutritional value for this mollusc species. 相似文献
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Hamada M. Abdelrahman Dan C. Olk Dana Dinnes Domenico Ventrella Teodoro Miano Claudio Cocozza 《Journal of Soils and Sediments》2016,16(10):2375-2384
Purpose
The study aimed to describe the carbohydrates and amino compounds content in soil, the light fraction (LF), the >53 μm particulate organic matter (POM), and the mobile humic acid (MHA) fraction and to find out whether the carbohydrates and amino compounds can be used to explain the origin of SOM fractions.Materials and methods
Soil samples were collected from two agricultural fields managed under organic farming in southern Italy. The LF, the POM, and the MHA were sequentially extracted from each soil sample then characterized. Seven neutral sugars and 19 amino compounds (amino acids and amino sugars) were determined in each soil sample and its correspondent fractions.Results and discussion
The MHA contained less carbohydrate than the LF or the POM but its carbohydrates, although dominated by arabinose, were relatively with larger microbial contribution as revealed by the mannose/xylose ratio. The amino compounds were generally less in the LF or the POM than in the MHA, while the fungal (aspartic and serine) and bacterial (alanine and glycine) amino acids were larger in the MHA than in the LF or the POM, underlining the microbial contribution to the MHA. Results from both sites indicated that total carbohydrates content decreased moving from the LF (younger fraction) to the MHA (older fraction), which seems to follow a decomposition continuum of organic matter in the soil-plant system.Conclusions
The study showed that the MHA is a labile humified fraction of soil C due to its content of carbohydrates and concluded that the content of carbohydrates and amino compounds in the LF, the POM and the MHA can depict the nature of these fractions and their cycling pattern and response to land management.68.
Bianchi DA Blanco NE Carrillo N Kaufman TS 《Journal of agricultural and food chemistry》2004,52(7):1923-1927
The synthesis of 6,7-dimethoxy-4-hydroxyisochroman-3-one 10 from 2,3-dimethoxytoluene (11) via glyoxylate 12 is reported. Compound 10 strongly inhibited vegetative growth of tobacco plants, whereas developmental patterns (protein levels, protein profile, pigments, and chlorophylls) were not affected. Morphological changes were observed in the leaves of the treated plants. 相似文献
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Rilner Alves Flores Aline Franciel de Andrade Derblai Casaroli Dayanna Teodoro Quirino Klaus de Oliveira Abdala Camila Martins 《Communications in Soil Science and Plant Analysis》2020,51(7):896-910
ABSTRACTPotassium (K) is closely associated to the improvement of sugarcane quality, acting in the conversion of reducing sugar (RS) to recoverable sugars (TRS). The present study aimed to evaluate the effect of different levels of K-fertilization on the yield and technological quality of sugarcane ratoons grown under edaphoclimatic conditions in the Brazilian central region. The experiment was carried out using the sugarcane variety CTC-4, in a Distrofic Latosols, medium texture (270 g clay kg?1). The study was arranged in a randomized complete block design, with five treatments (0; 50; 100; 150 and 200 kg K2O ha?1), and five replicates. Potassium content in soil and plant, biometric variables, stalk yield and the technological quality at harvest were evaluated. The 200 kg ha?1 dose increased the K content in 160, 156, 56 and 3% in 0–0.20 and 0.20–0.40 m layers at 180 and 360 days after budding (DAB), respectively, promoting greater absorption of the nutrient by plants (X ? = 15.22 g kg?1). The higher potassium absorption reflected in yield gains, with an increasing of 7.9%, compared to the control treatment, yielding 100.37 t ha?1. However, soil K fertilization did not affect the technological quality of the sugarcane ratoon.Abbreviations: K: potassium; RS: reducing sugars; TRS: recoverable sugars; DAB: days after budding; SB: Sum of Bases; CEC: Cation Exchange Capacity; V: Saturation Base; Kcl: potassium chloride; AWC: Available water capacity; PC: Pol percent in sugarcane; Brix: total soluble solids; dRYL: Dystrophic Red Yellow Latosol; eRYA: Eutrophic Red Yellow Argisol. 相似文献
70.
Dehydrogenase activity in Mediterranean forest soils 总被引：5，自引：1，他引：5
The dehydrogenase activity (DHA) in the upper 10 cm of forest soils was measured in three experimental plots (1 ha) in Los Alcornocales Natural Park (southern Spain). In each plot, a sylviculture treatment of thinning and shrub-clearing had been previously carried out in one half, while the other half was left as a forest control. Soil samples were taken during the dry season (July 2000) and after the first autumn rains (October 2000). The DHA of forest soil in autumn [527끭 nmol p-iodonitrotetrazolium formazan (INTF) g-1 h-1] was almost double that in summer (289ᇳ nmol INTF g-1 h-1), for one of the studied plots. During the dry season, DHA of forest control soils (324ᇩ nmol INTF g-1 h-1) was higher than in the thinned and shrub-cleared forest (253ᇱ nmol INTF g-1 h-1). During the autumn (wet season), however, the effects of the sylvicultural practices on the soil dehydrogenase were negligible. Significant differences in DHA were found between the three sites. Multiple regression analysis identified pH as the best predictor of DHA of these soils. Other soil properties (pH, K, Ca, Mg, and soil moisture) also showed significant correlations with DHA. In addition, clay content appeared to enhance the enzyme activity. Our results suggest that thinning and shrub-clearing in Mediterranean forests seem to affect negatively the soil DHA, and their impact is more marked during the dry season. However, season and site effects are better determinants of DHA than management practices. 相似文献