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111.
Common bean (Phaseolus vulgarisL.) is a traditional crop in Portugal, where farmers growvarieties selected and maintained by themselves. A collection of 88landraces of common bean was evaluated for 17 quantitative andqualitative traits and the biochemical marker phaseolin to displaythe degree of variation of this germplasm. Agronomic data weresubjected to cluster analysis and several groups were identified,with three groups clustering most of the landraces. Regardingphaseolin variation the C and T banding patterns are the mostfrequent ones, so the origin of the Portuguese beans is thus probablythe Andean region of South America. These results give informationabout the origin, diversity and breeding value of the Portuguesegermplasm, that could be useful to widen the genetic base ofcurrently cultivated bean varieties in Europe.  相似文献   
112.
Skeletal deformities constitute a major problem for aquaculture industry by decreasing the final value of the fish. An analysis of skeletal malformations in 11,640 fish was performed considering families and triplicates per family. Thirtynine different skeletal abnormalities were detected, such as lordosis, vertebral fusion, absence of one or both operculum, bent-jaw, etc. Moreover, a new unusual complex spinal column deformity consisting of a consecutive repetition of lordosis, scoliosis and kyphosis (LSK) from the head to the caudal fin was described. This syndrome was statistically associated with the family structure (Z2H–family,LSK=3.49; p<0.05). The incidence of this deformity was 0.2% in the whole population, and 6.5% within the affected family (2H). The environmental and genetic causes are discussed.  相似文献   
113.
In 2001 and 2002, an outbreak of a previously unreported disease, associated with a border disease virus (BDV), caused high mortality in the Southern chamois (Rupicapra pyrenaica) population in the Alt Pallars-Aran National Hunting Reserve in the Catalan Pyrenees (NE Spain). Between 2002 and 2006, sera and/or tissue samples taken from 116 healthy chamois shot during the hunting season, plus 42 from chamois affected by different diseases, were studied. A blocking enzyme-immunosorbent assay (ELISA) was used to study pestivirus seroprevalence in 114 healthy hunted and 31 diseased chamois, yielding positive results in 73.7 and 22.6% of the chamois, respectively. Comparative virus neutralization tests (VNT) performed on 42 seropositive samples with 6 pestivirus strains yielded statistically higher titres to BDV Spain 97, followed by BDV chamois, BDV 137/4, BDV Moredun, Bovine Diarrhoea virus-1 (BVDV-1) NADL and BVDV-2 atypical. Virological investigations for pestivirus detection were performed using an antigen ELISA test in 82 healthy and 18 diseased chamois, RT-PCR in 16 healthy and in all diseased chamois, and virus isolation in 14 diseased chamois. No viral antigen was detected in any of the healthy animals. A pestivirus, characterized as BDV by monoclonal antibodies, was detected in the 10 chamois showing clinical signs consistent with BDV infection. Sequence analysis in the 5' untranslated region (5'-UTR) revealed that they were grouped into the BDV-4 genotype. In the remaining chamois, infectious keratoconjunctivitis, pneumonia, trauma and contagious ecthyma were diagnosed. The cause of death was unknown in five chamois. The results suggest that the infection has become endemic in the population and that it could have a significant impact on chamois population dynamics.  相似文献   
114.
Salinity is a key factor limiting cirrus production in many world areas. The two citrus genotypes sour orange (Citrus aurantium L) and macrophylla (Citrus macrophylla Wester), that differ in their ability to restrict sodium (Na) and chloride (Cl) transport to the shoot under salt stress, were studied to compare the contribution of both inorganic and organic solutes in osmotic adjustment. Plants of both citrus genotypes were grown in isosmotic (0.23 MPa) solutions of different ionic composition (Na, NaCl, Cl, and concentrated macronutrients), and leaf and root solutes were measured to determine their relative contribution to osmotic adjustment. Both leaf water and osmotic potentials decreased in response to imposed stress in the nutrient media, regardless of the isosmotic treatment. Growth reduction was more severe in macrophylla than in sour orange, except for macronutrient treatment. The major components associated with the osmotic adjustment were inorganic solutes (ranging from 65 to 85% of total solutes) and organic solutes (ranging from 15 to 35%, depending on the genotype and the isosmotic treatment). Among these, carbohydrates were the major organic components (6–24%), with glucose the main osmoregulating sugar in Cl‐containing treatments. The contribution of the organic acids and amino acids to the osmotic adjustment of plant under saline stress seemed to be less important in these citrus species.  相似文献   
115.
The use of the fluorescent visible implant elastomer (VIE) tagging system in juvenile gilthead seabream, Sparus auratus L., between 7 and 18 g was examined. Four different colours (red, green, orange and yellow), three body positions (dorsal, lateral and caudal) and two orientations (horizontal and vertical) were tested. The mean tag application time for each fish was 15.7±0.32 s. There was no mortality associated with the method of tagging. The most visible tag colour was red. Injection orientation had a significant effect on length, width, fragmentation and fluorescent intensity of the tag. Horizontal tagging is recommended because of high fluorescent intensity, low fragmentation and for double tagging. There were no differences in growth between untagged controls and the VIE‐tagged fish.  相似文献   
116.
Living walls (LW) are vertical greening systems that are becoming popular due to their multiple social and environmental benefits. When LW are installed indoors, a lightening system is often required to ensure an appropriate plant development. This work assesses the performance of three artificial lighting systems on six indoor LW [0.7 m (wide) × 0.7 m (high)] placed at two distances from the light source. The plant species selected for the tests were Soleirolia soleirolii and Spathiphyllum wallisii, which are frequently used in indoor LW. Three different lamps were used in the experiment: incandescent (IL), fluorescent (FL) and metal halide (MHL) lamps, all of them with an input electric power of ≈250 W. Differences in plant growth were only observed when the LW were close to the light source (about 1 m) but not at greater distances (≈1.5 m). IL had the poorest performance. Despite the lower photosynthetic photon flux density efficiency of FL compared with MHL, FL light enabled plants placed in the upper LW (closer to light source) reached similar size to those grown under MHL. Plant quality attributes were generally not affected by light type or the distance to light source. IL and FL generated higher total water losses (i.e. transpiration plus evaporation) than MHL on a LW basis. When expressed per unit of LW area covered by vegetation, FL and MHL reduced water consumption by 34% and 56%, respectively, as compared to IL. Overall, our results indicate that both FL and MHL outperform IL and have a similar ornamental performance, whereas MHL are more advantageous than FL in terms of water consumption and annual cost.  相似文献   
117.
This study aims to assess the long-term economic viability of deficit irrigation (DI) strategies in almond trees (cv. Marta) grown in a semiarid area (southeast Spain). A discounted cash flow analysis (DCFA) was performed to determine the profitability of the different irrigation regimes. Four irrigation treatments were evaluated over the first 6 years of an almond plantation: (1) full irrigation (FI); (2) regulated deficit irrigation (RDI) receiving 40 % ETc during kernel-filling and 100 % ETc during the remainder of the growing season; (3) mild-to-moderate sustained deficit irrigation (SDImm), irrigated at 75 % ETc (first half of the experiment) and 60 % ETc (second half of the experiment) over the entire growing season; and (4) moderate-to-severe SDI (SDIms), irrigated at 60 % ETc (first half of the experiment) and 30 % ETc (second half of the experiment) over the whole growing season. Irrigation water profit was mainly determined by the annual volume of irrigation water applied (water costs are around 50 % of variable costs). DCFA indicates that RDI and SDImm are the most economically feasible treatments, whereas FI and SDIms presented a similar degree of profitability over the 6-year period. Simulation outputs derived for the whole useful life of the investment indicate that SDImm would be the most suitable irrigation treatment to be adopted by almond farmers in the study area. We conclude that in a context of water scarcity, DI is a financially feasible alternative to FI.  相似文献   
118.
We have studied the percentage of radiation transmitted through the tree canopy to the underlying pasture and crops in dehesas of Southwest Spain by means of fish-eye photographs taken at different distances from the tree. Thirty-six trees were studied covering all the diametric classes (0.1–14 m canopy width) of two stands, with mean density of 19 mature trees ha−1. Intercepted light decreased with distance following an logistic curve, indicating a rapid increase in the light availability with distance from the tree. For mature trees, radiation was constant beyond 20 m. Applying a multivariable regression light equation, distance, stem diameter and canopy width explained more than 88% of the light variability for each orientation studied. A simple model was built up from light equations, tree growth curves and allometric relationships. From this model, we have estimated that radiation available for crops and pasture decreased up to 21% due to the presence of trees in a standard dehesa with 24 mature trees ha−1 and 13% of canopy cover. In addition, we have generated different radiation maps of virtual dehesas differing in tree age, density and arrangement, which could be useful to determine optimal tree planting schemes and consequent pruning and thinning regimes.  相似文献   
119.
Atlantic salmon (Salmo salar) were fed 6 experimental diets containing three levels of arachidonic acid (ARA) (0.18 g kg?1, 0.28 g kg?1 and 0.63 g kg?1 for low, medium and high levels, respectively) and two levels of vitamin E (150 and 730 mg kg?1 for low and high levels, respectively). At the end of the experimental period, fatty acids in the liver and immunity markers (lysozyme activity, respiratory burst and phagocytic activity) were determined and fish subjected to a challenge test against the salmonid rickettsial syndrome (SRS) pathogen. ARA, vitamin E or their interaction did not exert an effect on fish performance, whereas ARA alone clearly increased the deposition of ARA. Dietary vitamin E only enhanced liver vitamin E deposition, while the interaction of ARA and vitamin E influenced lysozyme activity and EPA/ARA ratio pointing out the effect of both nutrients on the fish immune system and metabolism. Only the medium concentration contributed to reducing mortality when the fish were exposed to the SRS pathogen. In conclusion, different levels of supplementation with ARA and vitamin E in the diet had no effect on productivity, but did have effects on immune markers and cumulative mortality when fish were exposed to the SRS pathogen.  相似文献   
120.
Enteromyxoses are relevant diseases for turbot and gilthead sea bream aquaculture. The myxozoan parasites invade the intestinal mucosa, causing a cachectic syndrome associated with intestinal barrier alteration; nonetheless, their pathological impact is different. Turbot infected by Enteromyxum scophthalmi develop more severe intestinal lesions, reaching mortality rates of 100%, whereas in E. leei-infected gilthead sea bream, the disease progresses slowly, and mortality rates are lower. The mechanisms underlying the different pathogenesis are still unclear. We studied the distribution and expression changes of E-cadherin, a highly conserved protein of the adherens junctions, in the intestine of both species by immunohistochemistry and quantitative PCR, using the same immunohistochemical protocol and common primers. The regular immunostaining pattern observed in control fish turned into markedly irregular in parasitized turbot, showing an intense immunoreaction at the host–parasite interface. Nevertheless, E-cadherin gene expression was not significantly modulated in this species. On the contrary, no evident changes in the protein distribution were noticed in gilthead sea bream, whereas a significant gene downregulation occurred in advanced infection. The results contribute to the understanding of the different host–parasite interactions in enteromyxoses. Host and parasite cells appear to establish diverse relationships in these species, which could underlie the different pathological picture.  相似文献   
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