INFLUENCE OF CLAY SOIL ON TWO PROTEA CULTIVARS PLANTED DIRECTLY OR GRAFTED ON CLAY-SOIL RESISTANT ROOTSTOCK. STUDY OF SOIL FERTILITY,FOLIAR NUTRITION,AND NUTRIENT CONTENT OF CUT FLOWERS

Leucospermum is a genus of the Proteaceae family that has achieved an increasing importance in the market of cut flowers worldwide. Some Leucospemum plants do not grow properly in clay soils, but grafting on a clay-soil resistant rootstock could provide better performances. The nutrient composition of two cultivars of Leucospermum (‘High Gold’ and ‘Succession II’) cultivated in clay soil was evaluated planting them directly or grafting on Leucospermum patersonii rootstock. The assay consisted of four treatments, T1 = ‘High Gold’ planted directly, T2 = grafted ‘High Gold’, T3 = ‘Succession II’ planted directly, and T4 = grafted ‘Succession II’. The experiment was carried out over three years, following a randomized block design with four replications per treatment. Foliar calcium (Ca) decreased in grafted plants of both cultivars. Nitrogen, phosphorus, potassium, Ca, and magnesium contents of the cut-flowers of ‘High Gold’ treatments were higher than those of ‘Succession II’, though in the third year no comparison with T3 plants was possible because most of them had died. The studied nutrients removal by ‘High Gold’ exceeded those of ‘Succession II’.     

Phenoloxidase and peroxidase activity in the shrimp Litopenaeus schmitti,Pérez‐Farfante and Kensley (1997) exposed to low salinity

Phenoloxidase and peroxidase activity were analysed in haemolymph of juvenile shrimp, Litopenaeus schmitti, exposed to different salinity levels (35%, 18%, 8%) for 48 h. A significant reduction (P<0.05) in total glucose and phenoloxidase activity in animals exposed to lower salinities (18% and 8%) was recorded, while peroxidase activity and total protein concentration did not vary. Histology revealed the occurrence of oedema in gills in shrimp exposed to 8%. The work demonstrates for the first time that in L. schmitti, low salinities can decrease glucose levels in haemolymph and create an immunosuppressive state by reducing phenoloxidase activity.     

Modelling the potential distribution of two tropical freshwater fish species under climate change scenarios

1. Climate change is causing shifts in the distribution patterns of freshwater fish at various spatio-temporal scales. Tropical freshwater fish are vulnerable, especially in areas where a high impact of climate change is predicted; thus, there is an increasing need to predict these shifts to determine conservation and adaptation strategies.
2. Ecological niche models offer a reliable way to predict the effects of climate change on species distribution. Potential shifts in the distribution of tropical fish were tested under two scenarios (4.5 – moderate and 8.5 – extreme) with three general circulation models for years 2050 and 2070 using maximum entropy software using as models two predatory species – the tropical gar Atractosteus tropicus and the giant cichlid Petenia splendida.
3. The potential distribution of both species was associated with warm and humid–sub-humid conditions. Future projections showed a higher availability of suitable areas for both species resulting from the expansion of warmer conditions in the middle and upper basins of the Central American mountain range and centre of the Yucatan Peninsula.
4. Ecological niche models of keystone or umbrella species such as A. tropicus and P. splendida could be useful to support conservation plans of protected areas. The potential distribution of both species covers areas of high suitability including six important biosphere reserves in Mexico, three protected areas in Guatemala and part of the Mesoamerican biological corridor.
5. Despite the potential expansion of the present distribution range suggested by the models, it is important to consider the biological and ecological requirements of the species and the ecological implications of these potential shifts in distribution. Both scenarios could have several implications at genetic, population, and ecosystem levels.

     

Effects of sulfosulfuron soil residues on barley (Hordeum vulgare), sunflower (Helianthus annuus) and common vetch (vicia sativa)

The phytotoxicity and sensitivity of succeeding crops to the new sulfonylurea, sulfosulfuron, have been reported although there is insufficient data on the phytotoxic effect of field soil residues. Growth chamber bioassays were conducted to detect the presence of residues in soil samples previously treated with sulfosulfuron at the recommended rate and double rate (20 and 40 g a.i./ha) that could affect the succeeding crop. Soil samples were collected between 7 and 9 months after sulfosulfuron application in field selectivity assays at nine different locations in Northern and Central Spain. The bioassay test species were barley (Hordeum vulgare L.) ‘Graphic’, sunflower (Helianthus annuus L.) ‘Albasol’ and common vetch (Vicia sativa L.) ‘Neska’, typical crops grown in rotation with wheat (Triticum aestivum L.) in this area. Sulfosulfuron residues did not affect barley and common vetch, but inhibited shoot length, root length and root dry weight of sunflower seeded into some soils treated with the 2× rate (40 g a.i/ha) 9 months earlier.     

Comparison of Bioactive Compounds Content and Techno-Functional Properties of Pea and Bean Flours and their Protein Isolates

Plant Foods for Human Nutrition - Recently, legume protein isolates are increasingly of interest as ingredients for the food industry; however, in spite of their health benefits, there is a limited...     

Influence of Neospora caninum intra-specific variability in the outcome of infection in a pregnant BALB/c mouse model

Previous assays in pregnant animals have demonstrated the effect of different host factors and timing of infection on the outcome of neosporosis during pregnancy. However, the influence of Neospora caninum isolate itself has been poorly investigated. Here, we compared the effects on clinical outcome and vertical transmission observed in a pregnant mouse model following infection with 10 different N. caninum isolates. The isolates in our study included the Nc-Liv isolate and nine N. caninum isolates obtained from calves. Female BALB/c mice were inoculated with 2 × 10⁶ tachyzoites at day 7 of pregnancy. Morbidity and mortality, in both dams and offspring during the course of infection, and transmission to progeny at day 30 postpartum were evaluated. The serum IgG1 and IgG2a production in dams were also examined. All dams showed elevated IgG1 and IgG2a responses, confirming N. caninum infection, although signs of disease were only exhibited in dams infected with 4 of the 10 isolates (Nc-Spain 4H, Nc-Spain 5H, Nc-Spain 7 and Nc-Liv). In neonates, clinical signs were observed in all N. caninum-infected groups, and neonatal mortality rates varied from greater than 95% with the isolates mentioned above to less than 32.5% with the other isolates. Vertical transmission rates, as assessed by parasite PCR-detection in neonate brains, also varied from 50% to 100% according to the isolate implicated. These results confirm the wide pathogenic and transmission variability of N. caninum. The intra-specific variability observed herein could help us explain the differences in the outcome of the infection in the natural host.     

Effects of carbohydrate sources on growth,body composition and tissue lipid deposition of blackspot seabream,Pagellus bogaraveo (Brunnich)

Rearing blackspot seabream has been associated with low growth rates and excessive lipid accumulation, resulting in a reduction of the edible yield. The effect of extruded diets containing different carbohydrate sources (wheat vs. wheat bran) was evaluated on 100 g blackspot seabream growth performance, feed utilization and fat deposition, taking into consideration the optimal dietary protein and lipid level described for smaller‐sized fish. A fish meal‐based diet was also tested as a control to assure maximal growth rates were achieved. The experiment was held in sea cages at environmental conditions. Duplicate groups of fish were distributed among six cages with a stocking density of 1.3 kg/m³ and hand‐fed each diet for 7 months. At the end of the experiment, fish in all groups doubled their body weight attaining 190–230 g. Specific growth rate (0.3–04), feed conversion ratio (1.3–1.6) and protein gain (0.5–0.6 g/kg/day) were similar among treatments. The Hepatosomatic Index, the Viscerosomatic Index and final whole body composition did not vary significantly among dietary treatments; nevertheless, the inclusion of wheat bran induced a significant increase of liver lipid content and the highest mesenteric fat index. All diets were effective in reducing whole body and mesenteric fat compared with initial values.     

Diphasic sedimentation technique complemented by a statistical approach as a useful tool to the quantification and the determination of dynamics of eggs produced by adult monogenean parasitizing groupers,Epinephelus marginatus (Lowe, 1834), in captivity

Monogenean parasites create problems in confined fish, such as at aquaculture and aquariums facilities. Strategic timing of antihelminthic treatments should be based on the dynamics of monogenean egg production which requires egg quantification, but there is no standardized analytical method. The WHO diphasic sedimentation method for helminth quantification of eggs was applied in samples with tetrahedral and fusiform monogenean eggs from six specimens of confined groupers (Epinephelus marginatus) (31 m³ sea water tank; water temperature 21.1–14.4°C; photoperiod 9:53–15 h light; November 2011 to June 2012). Helminth eggs remain in the pellet, while most organic matter was removed forming a cap. In contrast, monogenean eggs are distributed within both the pellet and cap. The diphasic sedimentation method is suitable to quantify tetrahedral and total egg number by counting those eggs in the pellet and incorporing water temperature data to obtain a statistically significant model expression (R² = 0.943; R² = 0.809), while this approach only weakly predicted fusiform egg numbers (R² = 0.297). Fusiform egg numbers declined along November–December, and increased in February–March, until June. Tetrahedral eggs decreased in November–December, but did not increase until March. The trend of egg populations and best time for antihelminthic treatment application can be set by WHO technique with the statistical approach proposed.     

MDN-0170, a New Napyradiomycin from Streptomyces sp. Strain CA-271078

A new napyradiomycin, MDN-0170 (1), was isolated from the culture broth of the marine-derived actinomycete strain CA-271078, together with three known related compounds identified as 4-dehydro-4a-dechloronapyradiomycin A1 (2), napyradiomycin A1 (3) and 3-chloro-6,8-dihydroxy-8-α-lapachone (4). The structure of the new compound was determined using a combination of spectroscopic techniques, including 1D and 2D NMR and electrospray-time of flight mass spectrometry (ESI-TOF MS). The relative configuration of compound 1, which contains two independent stereoclusters, has been established by molecular modelling in combination with nOe and coupling constant analyses. Biosynthetic arguments also allowed us to propose its absolute stereochemistry. The antimicrobial properties of the compounds isolated were evaluated against methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli, Aspergillus fumigatus, and Candida albicans. The potent bioactivity previously reported for compounds 2 and 3 against methicillin-sensitive S. aureus has been extended to methicillin-resistant strains in this report.