Influence of Nitrogen Addition and Plant Root Parameters on Phytoremediation of Pyrene-contaminated Soil

Phytoremediation is a method in which plants, soil microorganisms, amendments, and agronomic techniques interact to enhance contaminant degradation. We hypothesized that bermudagrass (Cynodon dactylon L) and an appropriate amount of N fertilizer would improve remediation of pyrene-contaminated Captina silt loam soil. The soil was contaminated with 0 or 1,000 mg pyrene/kg of soil and amended with urea at pyrene-C:urea-N (C:N) ratios of 4.5:1, 9:1, 18:1, or unamended (36:1). Either zero, one, two, or three bermudagrass sprigs were planted per pot and ?33 kPa moisture potential was maintained. Pyrene concentrations, inorganic-N levels, shoot and root parameters, and pyrene degrader microbial numbers were measured following a 100-day greenhouse study. At a C:N ratio of 4.5:1, the presence of plants increased pyrene biodegradation from 31% for the no plant treatment to a mean of 62% for the one, two, and three plant treatments. With no plants and C:N ratios of 4.5:1, 9:1, 18:1, and 36:1, the mean pyrene biodegradation was 31, 52, 77, and 88%, respectively, indicating that increased inorganic-N concentration in the soil reduced pyrene degradation in the treatments without plants. Additionally, none of the one, two, or three plant treatments at any of the C:N ratios were different with a mean pyrene degradation value of 69% after 100 days. Pyrene resulted in reduced shoot and root biomass, root length, and root surface area, but increased root diameter. The pyrene degrading microbial numbers were approximately 10,000-fold higher in the pyrene-contaminated soil compared to the control. At the highest N rate, bermudagrass increased pyrene degradation compared to the no plant treatment, however, in the unvegetated treatment pyrene degradation was reduced with added N.     

Benefits of using the probiotic Efinol®L during transportation of cardinal tetra, Paracheirodon axelrodi (Schultz), in the Amazon

The objective of this experiment was to test the probiotic Efinol^®L during transportation of cardinal tetra, Paracheirodon axelrodi (Schultz). For the transportation, fish were distributed in 18 plastic tanks, of which nine contained the Efinol^®L (10 mg L⁻¹; probiotic treatment) and the remaining had no probiotic (control treatment). Transport lasted 24 h and three different boxes of each treatment were sampled at 3, 12 and 24 h. Up to the 12-h sampling period, no significant difference in the survival was observed; on the other hand, survival was higher at the end of the transport (24 h) in the probiotic treatment. No significant difference was found in dissolved oxygen and temperature between treatments. Conductivity, pH and alkalinity increased along the transport, but without a difference between treatments. Ammonia increased in all treatments, although it was significantly lower in the probiotic group at 24 h. Cortisol levels were significantly higher in all transported fish when compared with the basal values. At 24 h, cortisol levels in control fish were significantly higher than those in the probiotic treatment. With the observed results, we are able to conclude that the probiotic Efinol^®L is efficient during cardinal transport, lowering the mortality and helping maintain water quality possibly by lowering metabolic wastes.     

Integrating functional diversity into tropical forest plantation designs to study ecosystem processes

? The elucidation of relationships between biodiversity and ecosystem processes has been limited by the definition of metrics of biodiversity and their integration into experimental design. Functional trait screening can strengthen the performance of these designs.

? We suggest the use of Rao’s quadratic entropy to measure both functional diversity and phylogenetic diversity of species mixtures proposed for an experimental design, and demonstrate how they can provide complementary information.

? We also present an index assessing the statistical performance of these independent variables in different experimental designs. Measurement of independent variables as continuous vs. discrete variables reduces statistical performance, but improves the model by quantifying species differences masked by group assignments.

? To illustrate these advances, we present an example from a tropical forest tree community in which we screened 38 species for nine functional traits. The proposed TropiDEP design is based on the relative orthogonality of two multivariate trait axes defined using principal component analysis.

? We propose that independent variables describing functional diversity might be grouped to calculate independent variables describing suites of different traits with potentially different effects on particular ecosystem processes. In other systems these axes may differ from those reported here, yet the methods of analysis integrating functional and phylogenetic diversity into experimental design could be universal.

     

Using Efinol®L during transportation of marbled hatchetfish, Carnegiella strigata (Günther)

The objective of this experiment was to test the efficacy of a probiotic (Efinol^®L) during transportation of marbled hatchetfish, Carnegiella strigata . Wild specimens were captured from a small stream and transported for 24 h in plastic fish boxes with a probiotic (10 mg L⁻¹) and probiotic-free water. The boxes were sampled at 3, 12 and 24 h of transport. At the end of the experiment, the survival rate was close to 100% in both treatments. Dissolved oxygen diminished with time in both treatments, but the probiotic group had significantly higher levels. Conductivity, pH and ammonia increased significantly during the transport, demonstrating higher levels in the probiotic-free group. Fish from both treatments presented very high net Na⁺ and K⁺ effluxes after 3 h of transport. At 24 h, net K⁺ effluxes in fish of the probiotic treatment reached values close to zero and a significantly lower Na⁺ efflux was observed. Cortisol levels in both treatments at 3 and 12 h were significantly higher than that in control samples. Higher body cortisol levels were observed in the probiotic-free group than that in the probiotic group at 3 and 12 h. The results demonstrate that addition of a probiotic during fish transport improves water quality and leads to fish presenting a lower stress response intensity.     

Dietary phosphorus restriction affects bone metabolism,vitamin D metabolism and rumen fermentation traits in sheep

Homeostasis of calcium (Ca) and phosphate (P_i) is maintained by a concerted interplay of absorption and reabsorption via the gastrointestinal tract and the kidney and by storage and mobilization from the bone regulated mainly by parathyroid hormone (PTH), 1,25-dihydroxycholecalciferol and calcitonin. The present study aimed at characterizing the effects of dietary P restriction on bone, vitamin D metabolism and rumen fermentation traits reflecting the endogenous P cycle maintaining the ruminal P supply for microbial metabolism. The experiments were done in eleven female, non-pregnant, non-lactating four- to nine-year-old Black Headed Mutton sheep allotted to two feeding groups: "P-restricted" (0.11% P/kg DM and 0.88% Ca/kg DM) and "Control" (0.38% P/kg DM and 0.88% Ca/kg DM). Dietary P restriction did not lead to hypophosphataemia, probably due to a compensation by bone mobilization, demonstrated by increased serum concentrations of a resorption marker and altered gene expression in bone tissue. In addition, the RNA expression of fibroblast growth factor 23, a bone-derived factor involved in the regulation of vitamin D metabolism, was significantly reduced with dietary P restriction. Furthermore, several genes related to vitamin D metabolism and plasma concentrations of 1,25-(OH)₂D were associated with serum concentrations of phosphate (P_i). In the parotid gland, the expression of the P_i transporter NaPi2b was negatively associated with serum P_i and positively with parathyroid PTH expression. Although P_i concentrations in saliva and the gastrointestinal tract were significantly reduced, we found no adverse effects of the P-restricted ration on the production of short chain fatty acids, but slight differences in the production of butyrate as well as its relationship to rumen P_i and ammonia concentrations that might indicate an impact on ruminal fermentation.     

Dietary supplementation with curcumin-loaded nanocapsules in lambs:Nanotechnology as a new tool for nutrition

Curcumin-containing nanocapsule powder formulations have not been used in ruminant feed to date, despite the fact that curcumin is known to be a functional food additive. The objective of this study was to determine whether ethyl polymethacrylate (Eudragit L-100) nanocapsules loaded with curcumin (N-CU) would improve health and growth of lambs. Thirty-two male Lacaune lambs (body weight [BW] = 16 ± 0.99 kg; 45 d of age) were randomly assigned to 1 of 4 treatments: T0, T1, T2 and T4, representing supplementation of curcumin at 0, 1, 2, and 4 mg/kg concentrate, respectively. The animals in each treatment were allocated in 4 pens of 2 lambs each (8 lambs per treatment). The experiment lasted 17 d, with samples and measurements collected on d 0, 7, 12, and 17. The T2 lambs had greater average daily gain than T0 lambs. Regression analysis showed that the ideal dose of N-CU to enhance weight gain was 1.89 mg/kg concentrate. There were significant interactions (P < 0.05) between treatments × time for hematological variables, particularly for increases in erythrocytes (T2) and reductions in counts of leukocytes, neutrophils, and lymphocytes in T1 and T2. There were significant interactions between treatment × time for total protein, globulin, urea, and triglyceride levels. Stimulation of the antioxidant system was also observed. There were increased levels of non-protein thiols (NPSH), as well as increased activities of superoxide dismutase (SOD) and glutathione S-transferase (GST) in the supplemented animals. Levels of reactive oxygen species (ROS) were lower in the serum of supplemented lambs. In general, the 4 mg/kg dose had no positive effects on growth or health. This was an unexpected result, given the known properties of curcumin. Taken together, these findings suggest that addition of low concentrations of nanoencapsulated curcumin (T1 and T2) in lamb feed improves health, minimizing oxidative stress and generates anti-inflammatory effects that may have contributed indirectly to greater weight gain. Nanocapsules potentiate the effects of curcumin and may emerge as a new tool in animal nutrition.     

Changes in fruit maturity indices along the harvest season in ‘Algerie’ loquat

Loquat is a subtropical fruit tree that presents an annual cycle reverse to that of the well-known temperate fruit crops. Loquat rests during summer, blooms in autumn, develops its fruit through winter and ripens them in early spring. Its unusual phenology allows growers to obtain high prices for its fruits, especially for early harvests. Although loquat is harvested based on skin colour, a minimum soluble solid content (TSS) of 10° Brix is often required for commercialization. However, we have noticed that the relationship between skin colour and eating quality seems to change along the season leading costumers to complain for the high acidity of the earliest fruits. In order to establish a reliable maturity index, we have evaluated the changes in different fruit maturation parameters along the harvest period in four consecutive seasons for ‘Algerie’ loquat. The results show that in samples collected with similar skin colour, TSS and, especially, fruit titratable acidity (TA) tend to decline as harvest season progresses. This makes fruit skin colour on its own not suitable as a harvest index to assure an adequate fruit quality under all circumstances. We propose instead to monitor continuously TSS and TSS/TA ratio along the season in order to fulfill consumer's expectations.     

Successful treatment of Corynebacterium urealyticum encrusting cystitis with systemic and intravesical antimicrobial therapy

A 6-year-old Saint Bernard dog was diagnosed with encrusting cystitis caused by Corynebacterium urealyticum. The infection persisted despite the prolonged use of antimicrobials and surgical debridement of the urinary bladder. Resolution occurred following intravenous vancomycin, urine acidification, and intravesical gentamicin. The challenges involved in the treatment of encrusting cystitis are described.     

Influence of gaps on some selected tree characteristics of edge trees in Norway spruce plantations

The present study examined branch and stem characteristics of trees growing around gaps in Norway spruce plantations. Trees located at the edge of gaps with a radius of either 5 m or 7 m either unplanted or with supplementary planting were compared to trees in the original closed plantation. The experiment was carried out in two locations in the south of Sweden and the design included four blocks at each location and one replicate of each treatment in each block. The measurements were carried out on standing and felled trees in 2005 at the time of the first thinning. The results indicate a significant effect of gaps and supplementary planting on the diameter of the largest branch, the number of living branches close to breast height, branch basal area, height to the first living branch and taper. The effect of supplementary planting on branch and stem characteristics was greater in large gaps than in small ones. This study indicated that supplementary planting may be useful in affecting stem-form and branch parameters, although other studies have shown that the trees that result from supplementary planting contribute little to total production.