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121.
Ariana Silva Guimarães Paulo Travassos Pedro Walfir Martins E Souza Filho Fabrício Dias Gonçalves Francisco Costa 《Aquaculture Research》2010,41(6):828-838
The conversion of mangrove areas into shrimp farming ponds has been indicated as the main activity responsible for the reduction in the area of this ecosystem along the northeastern coast of Brazil. The present study was conducted using remote sensing methods and a geographical information system with the aim of quantifying the participation of this activity in the reduction of the mangrove areas along the northern coast of the State of Pernambuco (northeast, Brazil), where shrimp farming has been implanted in last recent years. From 1973 to 2005, there was reduction of about 2.052 ha of mangrove, 197 ha of which were converted into shrimp ponds. Thus, the real contribution of shrimp farming to this reduction was just 9.6% of the total area. Other anthropogenic activities, such as agriculture, urban expansion and tourism, contributed greatly to the reduction in the mangrove areas along the northern coast of the State of Pernambuco. 相似文献
122.
Hortência Aparecida Botelho Aline de Assis Lago Alisson Lucrecio da Costa Adriano Carvalho Costa Rafael Vilhena Reis Neto Zoraia Silva Fagner Machado Ribeiro Marcos Barcellos Caf Rilke Tadeu Fonseca de Freitas 《Aquaculture Research》2019,50(9):2429-2436
The objective of this study was to verify the direct and indirect correlation between morphometric measures, ratios, body weight and yield in two lambari species Astyanax lacustris and Astyanax fasciatus and whether the discriminant analysis is capable of separating and allocating the species. We used 102 lambari yellow tail and 60 lambari red tail. The fish were weighed and submitted to the evaluation of the morphometric measurements. The direct and indirect effects were evaluated by the method of track analysis, considering weight at slaughter, weight of body parts and body yields as dependent variables and measures and morphometric ratios as explanatory variables. Astyanax lacustris presented higher height and body width, carcass yield and trunk, while A. fasciatus presented higher head yield and viscera weight. The discriminant analysis was able to classify 79.5% of the two species. Track analysis demonstrated that the morphometric measurements can be used for estimation of body and body components’ weight in A. lacustris and A. fasciatus. However, regarding the corporal yield; the morphometric measures were insufficient to explain the yield variations of the species. 相似文献
123.
Natalino da Costa Sousa Mrcia Valria Silva do Couto Higo Andrade Abe Peterson Emmanuel Guimares Paixo Carlos Alberto Martins Cordeiro Emilly Monteiro Lopes Jonathan Stuart Ready Gabriel Fernandes Alves Jesus Mauricio Latera Martins Jos Luiz Pereira Mourio Paulo Csar Falanghe Carneiro Alexandre Nizio Maria Rodrigo Yudi Fujimoto 《Aquaculture Research》2019,50(12):3720-3728
Intensive fish farming has resulted in an increased concern for disease outbreaks. Probiotic use is one of the strategies being developed to improve fish health and productivity. Measures of probiotic colonization, growth performance, haematological characteristics and parasite load were used to evaluate the effect of diets supplemented with Enterococcus faecium on growth and health of Arapaima gigas juveniles. A completely randomized design with four treatments (diet with E. faecium at 1 × 106 CFU/g and 1 × 108 CFU/g, control diet and diet with the culture medium MRS) and three replicates was used. Ninety‐six Arapaima juveniles were distributed in 12 cages fed with the specified diet for 68 days. Colonization of the intestinal tract by lactic acid bacteria reduced the total number of heterotrophic bacteria in fish fed with probiotics compared to controls. Fish fed a supplemented diet containing 1 × 108 CFU/g presented higher values of weight gain, survival and fish growth uniformity, and lower values of feed conversion ratio. The prevalence of Trichodina sp. could have affected the survival of fish in the control group. Reduction in parasite load and an increase in haematocrit, the number of erythrocytes, thrombocytes, neutrophils and monocytes were also observed in fish fed the diet containing 1 × 108 CFU/g. Enterococcus faecium presented a probiotic effect in A. gigas juveniles and can be recommended for use at a concentration of 1 × 108 CFU/g to modify the gut microbiota, improve growth performance and haematology and reduce parasitic load. 相似文献
124.
Luis Artur Vales Bezerra Matheus Oliveira Freitas Vanessa Salete Daga Thiago Vinicius Trento Occhi Larissa Faria Ana Paula Lula Costa Andre Andrian Padial Viviane Prodocimo Jean Ricardo Simes Vitule 《Fish and Fisheries》2019,20(4):620-639
While environmental alterations have made Homo sapiens the hyperkeystone species of the globe, biotic homogenization initiated a new era, the “Homogenocene.” Still, some terrestrial and aquatic ecosystems in South America are considered pristine and wild, which can lead to a general faith that economic progress is consistent with conservation strategies, even without scientific support. We compiled anthropogenic threats to fish biodiversity in a hierarchical meta‐analysis, along with an evidence synthesis of threats related to biological invasions, based on peer‐reviewed research with the aim to represent the actual conservation status of the South American ichthyofauna. We highlighted human‐related threats and synergistic effects of biological invasions, climate change, environmental alterations (e.g., pollution, aquaculture and damming) and fisheries. Considering measures that reinforce novel alien fish (e.g., artificial hybrids or genetically modified) introductions, it became clear why an eventual increase in local or regional species richness is not always beneficial to aquaculture, biodiversity, human well‐being or nature. In fact, citizens in all societal roles, including scientists, should revise their concepts about threats to fish biodiversity. Environmental policies require more than taxonomic diagnostics to achieve conservation goals under an incompatible scenario of a multiplying number of fish species and biotic homogenization. We advocate for countries in South America using science‐based strategies useful to maintain their social and economic growth along with their “remaining nature.” We live a crucial moment when the government overlooks threats to biodiversity and uses agribusiness as the most acceptable manner of fuelling the economy. 相似文献
125.
Ana Lilia Alzate-Marin Marcia Regina Costa Klever Marcio Arruda Everaldo Gonçalves de Barros Maurilio Alves Moreira 《Euphytica》2003,133(2):165-169
Ouro Negro (Honduras 35) is a highly productive Mesoamerican black seeded bean cultivar that possesses a major dominant gene
conferring resistance to anthracnose (causal organism Colletotrichum lindemuthianum). In this work the anthracnose resistance gene present in Ouro Negro was characterized by studying allelic relationships
to the following previously characterized anthracnose resistance genes (cultivars): Co-1 (MDRK), Co-1
2 (Kaboon), Co-1
3 (Perry Marrow), Co-2 (Cornell 49-242), Co-3 (Mexico 222), Co-4 (TO), Co-4
2 (SEL 1308), Co-5 (SEL1360), Co-6 (AB 136), and the resistance genes present in PI 207262 and Widusa. In addition, we determined the resistance spectrum of
Ouro Negro in relation to 19 pathotypes of C. lindemuthianum. The allelism tests confirmed that the dominant anthracnose resistance gene present in Ouro Negro is positioned at a locus
distinct from those with which it was compared. We propose that this new gene be named Co-10. The inoculation of Ouro Negro with the 19 pathotypes of C. lindemuthianum demonstrated that Co-10 confers resistance to pathotypes 23, 64, 67, 73, 81, 83, 87, 89, 95, 102, 117, 119, 343, 453, 1033, 1545 and 1600. The identification
of Co-10 is an important contribution to bean breeding programs that are in constant need of new sources of resistance to anthracnose.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
126.
Christiane A. da Costa Valdir Lourenço Jr Michele F. Santiago Josiene S. Veloso Ailton Reis 《Plant pathology》2022,71(3):621-633
Septoria leaf spot, caused by Septoria lycopersici, is considered one of the most important diseases of tomato in Brazil. Despite its importance, the disease agent is still poorly studied. Septoria isolates collected from different production regions of Brazil were characterized by molecular, morphological, and pathogenic methods. A set of 104 isolates was sequenced for the DNA Tub, Cal, and EF1-α loci. Ten isolates were selected, according to geographical region of origin and type of leaf lesion (typical or atypical), for morphological characterization and for evaluation of aggressiveness on tomato cultivar Santa Clara. To evaluate the pathogen host range, cultivated and wild Solanaceae plants were inoculated with four selected isolates. The results showed that all isolates grouped with the type isolate of S. lycopersici in maximum likelihood and Bayesian inference trees. The isolates were morphologically similar. All isolates selected for pathogenicity testing on tomato were able to induce typical symptoms of the disease, but differed in their aggressiveness. A total of eight species of Solanaceae were also identified as potential alternative hosts for S. lycopersici. This information will provide a more accurate assessment of the risks involved with the introduction of new crops, especially of the genus Solanum, in areas where the species is already present. In addition, it will provide the basis for the establishment of more efficient methods in the management of Septoria leaf spot of tomatoes in natural conditions and in the different production systems. 相似文献
127.
S. N. Costa C. A. D. Bragança L. R. Ribeiro E. P. Amorim S. A. S. Oliveira M. A. Dita F. F. Laranjeira F. Haddad 《Plant pathology》2015,64(1):137-146
Panama disease, caused by Fusarium oxysporum f. sp. cubense (Foc), is ranked among the most destructive diseases of banana. The use of resistant varieties is the most desirable and effective control measure. Information on the pathogen population structure is essential, as durability of the resistance and effective cultivar deployment are strongly linked to this structure. In this study, 214 Foc isolates from different banana producing states in three regions of Brazil (northeastern, southeastern and southern) were analysed. Initially, nine microsatellite markers (SSR) were tested, which revealed 52 distinct haplotypes distributed in the different geographical regions and cultivars. While amova analysis showed that 68·01% of the total variation occurred within states, correlation between genetic and geographical distances was only found in the southern region. Results indicated that isolates from different states comprise a single population, which is predominantly clonal. When isolates representing different haplotypes were inoculated in four banana cultivars, differences in severity were found, with the high severity values being caused by isolates from haplotypes H7, H31 and H41. The diversity found here points to the need for additional studies, as this characteristic may be related to Foc's evolutionary potential and possibly to its ability to overcome the resistance from breeding programme‐generated cultivars. This is the most comprehensive study on population biology of Foc in Brazil. 相似文献
128.
João M. S. Carvalho Ricardo V. Costa Sandra Marnoto Célio A. A. Sousa José Carvalho Vieira 《Growth and change》2018,49(2):266-285
Based on an extensive literature review on intelligent cities, smart cities, and happy cities, and on their conceptual connections with citizens' well‐being, quality of life, and happiness, we developed a resource‐based view on City Quality: the PESNAT (political, economic, social, natural, artificial, and technological) framework. The concept of City Quality rests on the idea of cities interconnected sub‐habitats—PESNAT—which are powerful analytical categories needed for understanding cities as complex and intricate loci. This framework eventually aims at assessing the cities' power to attract businesses and people, to contribute to a sustainable development of the city and an increased quality of life. Furthermore, two hypotheses are outlined regarding the level of importance of each sub‐habitat in relation to happiness, and the level of controversy of each one for citizens, city planners, and decision makers. 相似文献
129.
Soybean seed coat chitinase as a defense protein against the stored product pest Callosobruchus maculatus 下载免费PDF全文
130.
Distribution patterns of loliginid squid paralarvae in relation to the oceanographic features off the South Brazil Bight (22°–25°S) 下载免费PDF全文
Loliginid squids constitute marine resources of increasing importance in shelf ecosystems off the coast of South Brazil. However, the existing information and knowledge about the occurrence of early‐life stages and causes of distributional patterns are insufficient. Here, we have revisited Brazilian historical plankton samples obtained from 11 oceanographic surveys to identify paralarvae and their abundances over time. The study area and time period cover the region between Cabo de São Tomé (22°S) and Cananéia (25°S) at depths down to 200 m from 1991 to 2005. Of the 246 paralarvae quantified, ~50% were identified to the genus or species level, including Doryteuthis spp. (D. sanpaulensis and D. plei), Lolliguncula brevis and a single specimen of Pickfordiateuthis pulchella. Paralarval occurrence and abundance peaked in different areas and were associated with distinct oceanographic conditions: D. sanpaulensis occurred in the northern region associated with cold waters and upwelling events, D. plei occurred primarily in the southern region of the study area and in warmer waters, and L. brevis was found in shallow and low salinity waters in the estuarine region off the coast of Santos. Overall, the highest abundance of paralarvae occurred in the nearshore, northernmost areas during summer, and this can be associated with the observed retention mechanisms caused by local circulation, seasonal upwelling, the intrusion of nutrient‐rich waters, and spawning peaks. The present study provides new information and evidence for loliginid patterns in the area that may potentially be useful for better understanding the recruitment patterns and fishery assessments of squid populations. 相似文献