978 resultados para Ornamental


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The efficacy of three feeds incorporated with different probiotics -Lactobacil, Vizylac and Cyfolac as nutrient supplement was evaluated in an ornamental fish, Carassius auratus (Linn.). The basal diet (40% protein) was prepared and the probiotics were incorporated at different levels viz. Lactobacil at 8x10 super(7)/100g and 12x10 super(7)/100g, Vizylac at 8x10 super(7)/100g and 12x10 super(7)/100g and Cyfolac at 12x10 super(7)/100g. Feeding trial was conducted for a period of 4 weeks. At the end of the experiment, bio-growth parameters and proximate composition of the fishes were studied. The growth, survival and protein content were improved in all the probiotic fed fishes compared to control. The maximum growth (0.74 g) and survival (85%) were observed in fishes fed with Lactobacil at 12x10 super(7)/100g. It emphasizes that supplementation of feed with probiotics has a positive impact on the growth, survival and the body composition of goldfish.

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Honey Gourami, Colisa sota, has high ornamental as well as food value. The natural resources of this species are gradually declining, due to destruction of its habitat, over fishing for aquarium trade and human consumption. The fish was bred in captivity under controlled environment. It laid about 200-400 eggs in bubble nest built by the male. Hatching started within 28-30hrs. after egg laying. The hatchlings became free swimming by 3rd to 4th day of hatching. The male showed territoriality and parental care by guarding the eggs and hatchlings. The larval survival was 30-35%. The breeding behavior, embryonic and post embryonic development of the fish were studied.

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Water hyacinth is a free-floating waterweed native to the Amazon River Basin in South America. In its native range, water hyacinth is not an environmental problem, although the weed is one of the most invasive alien plants in freshwater environments. Water hyacinth has the potential to become invasive through fast vegetative reproduction and rapid growth to accumulate huge biomass and extensive cover in freshwater environments. Over the last 150 years water hyacinth has invaded most countries in the tropics and sub-tropics, introduced by man, mainly for ornamental purposes. Such introductions led to the infestation of most freshwater-ways in the southern United States of America, parts of Australia, the pacific islands, and most countries in Asia and Africa. The extensive tightly packed mats of water hyacinth are often associated with devastating socio-economic and environmental impacts. Invasion by the weed has, therefore, often generated urgent costly problems associated with the weed biomass and its management. A classic example of such problems was triggered by the invasion and proliferation of water hyacinth in the Lake Victoria Basin during the 1980s (Freilink 1989, Taylor 1993, Twongo et al., 1995). The weed infestation marked the beginning of a decade of intensive and systematic campaign by the three riparian states (Kenya, Tanzania and Uganda) to bring weed proliferation under control. The discussions in this Chapter span over ten years of dealing with the challenges paused by the imperative to manage infestations of water hyacinth in the Lake Victoria Basin. The challenges included the need to understand the dynamics of water hyacinth infestation; its distribution, proliferation and impact modalities; and the development and implementation of appropriate weed control strategies and options. Most specific examples were taken from the Ugandan experience (NARO, 2002).

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A reduction in native fish stocks and the need to increase fish production for food, recreation, ornamental purposes and to control disease vectors and weeds have often justified and led to introduction of non-native fishes. Some of these introductions have been followed by benefitial and others by undesirable consequences. For instance introduction of the Nile perch Lates niloticus L. and several tilapiine species into lakes Victoria and Kyoga, and the clupeid Limnothrissa miodon into lakes Kariba and Kivu have resulted in increases in the quantity of fish available to the people around them. Predation by Nile perch and competition with introduced tilapiine species in lakes victoria and Kyoga have caused a severe decline and in some cases total disappearance of many of the native fish species.therefore the concern about fish introductions arises

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Lakes Victoria and Kyoga had, a diverse fish fauna, which was important as food for local population and valuable in scientific studies. Over the past twenty years, the diversity of fish in these lakes had declined due to over-exploitation, introduction of new fish species including the piscivorous Nile perch and degradation of fish habitat. Studies of satellite lakes in the Victoria and Kyoga lake basins suggested that some of these lakes harboured species which had been lost from the main lakes. In order to better understand the extent, to which these satellite lakes may serve as refugia, a faunal survey was undertaken to determine the distribution and nature of the taxa found. Seven satellite lakes and the eastern end of the main Lake Kyoga adjacent to these minor lakes were surveyed over a two-year period for fish species diversity. A total of 68 fish species were recorded of which 41 were haplochromines. Almost all the native non cichlids which occurred in the main lakes (Victoria and Kyoga) before the Nile perch upsurge recorded. Lakes Nawampasa, Gigati, Kawi, Agu and Nyaguo had the highest fish species and trophic diversity. The trophic diversity of haplochromines (based on Shannon Weaver Index) was highest in Lake Nawampasa (1.28), followed by Gigati (1.25), Kawi (1.18), Agu (0.8), Lemwa (0.81), Nyaguo (0.35) and was lowest in the main Lake Kyoga. Potential threats to these lakes were from collectors of ornamental fish species, especially the haplochromines, the spread of the predatory Nile perch and the water hyacinth, which are already in Lake Kyoga, and the destruction of macrophytes through harvesting of papyrus and reclamation for agriculture. The human population around these lakes harvested the fishes for food but the levels of exploitation were still low because the lakes were adjacent to main Lake Kyoga, the major supply of fish. Ornamental fish dealers were encouraged to start captive breeding of the fish for export to reduce pressure on the lakes and demonstrations for breeding were set up at FIRI in Jinja. Meetings and seminars were held with some of the communities living around the lakes sampled and the importance of fish species found in these lakes and the dangers of destructive practices discussed. Representatives of all taxa of fish caught from the lakes were preserved, catalogued and stored in the FIRI Museum. Results from this survey support the motion that these satellite lakes are important refugia for endemic diversity. Based on survey, we recommend that SaIne of these lakes like Nawampasa, Gigati, Kawi, Agu and Nyaguo could be designated as conservation areas of species threatened in the main lakes. One of the factors that seem to have prevented the spread of Nile perch into Kyoga Minor lakes seems to have been the presence of extensive swamps around these lakes and the low oxygen levels that exist in these habitats. Clearing of swamps and vegetation that separate Kyoga minor lakes from the main lake should be avoided to prevent Nile perch from spreading into these lakes.

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Data of classification, origin, pathway and environmental impacts of invasive alien micro-organisms, invertebrates, amphibians and reptiles, fish, birds, mammals, weeds, trees, and marine organisms in terrestrial, aquatic and marine ecosystems of China, were analyzed, based on literature retrieval, field survey and consultation. Some 283 invasive alien species were recorded in China, including 19 invasive alien micro-organisms, 18 aquatic plants, 170 terrestrial plants, 25 aquatic invertebrates, 33 terrestrial invertebrates, 3 amphibians and reptiles, 10 fish, and 5 mammals. Of the invasive alien species, 55.1% originated from North and South America, 21.7% from Europe, 9.9% from Asia, 8.1% from Africa and 0.6% from Oceania. Many institutions and individuals in China lack adequate knowledge of ecological and environmental consequences caused by invasive alien species, with some ignorance of the dangerous invasion in the introduction of alien species. For instance, 50.0% of invasive alien plants were intentionally introduced as pasture, feedingstuff, ornamental plants, textile plants, medicinal plants, vegetables, or lawn plants, 25% of alien invasive animals were intentionally introduced for cultivation, ornament, or biological control, In addition, more efforts are being made in the introduction of alien species, and little attention is paid on the management of introduced alien species, which may cause their escape into natural environment and potential threats to the environment. There were also gaps in quarantine system in China. All microorganisms were unintentionally introduced, through timber, seedling, flowerpot, or soil; 76.3% of alien invasive animals invaded through commodity or transportation facility because of the failure of quarantine. Therefore, quarantine measures should be strictly implemented; and meanwhile the intentional introduction of alien species should be strictly managed and a system of risk assessment should be implemented.

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Primula obconica was introduced to Europe from Hubei, China in 1880, and has been cultivated worldwide as one of popular ornamental plants. The volatile oil of wild P. obconica collected from its original place, Yichang, Hubei was first investigated. A total of 43 compounds constituting 93.49% of the oil were identified by using GC and GC-MS. The major compounds were methyl 2,4-dihydroxy-5-methyl benzoate (30.41%), methyl 2,6-dihydroxy-4-methyl benzoate (29.27%), and hypnone (8.92%) etc. In comparison with the published data of some European cultivars, the native P. obconica seems to be allergen-free due to absence of primin and miconidin.

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通过对14种草本花卉在Cd、Cd-Pb、Cd-Pb-柴油、Cd-甲胺磷等单一与复合污染条件下的耐性及重金属积累特性研究,就这些花卉对污染土壤修复的资源潜力有了大致的认识,为污染环境的生态修复及其集成技术的创新与应用提供了科学依据,同时也提供了具有我国自主知识产权的污染土壤修复材料的基本信息。通过盆栽实验,发现黄蜀葵、醉蝶、金盏菊、凤仙、蜀葵和紫茉莉六种植物对Cd单一污染表现出较强的耐性,约占参试花卉种的43%,说明花卉植物较有耐重余属的潜力。金盏菊在实验浓度下,地上部富集系数大于1且地上部的Cd含量大于根部含量,表现出重金属超积累植物的基本特征,但在本试验条件下还没有达到100mgkg-1Cd的超积累植物临界含量特征,因此,有待进一步实验证实。熔液培养条件下,黄蜀葵、紫茉莉、凤仙、万寿菊、串红五种花卉种子发芽对Cd表现为较强的耐性,因为其种子发芽率在Cd污染暴露条件下无明显影响(p>0.05)。但是,Cd对这五种花卉幼苗期根伸长的影响较为显著(p<0.05),并且Cd与花卉植物的幼苗期根长抑制之间存在线性相关关系。在复合污染条件下(Cd-Pb,Cd-Pb-柴油),14种参试花卉种,除金鸡菊和观赏向曰葵两种花卉表现出生物量明显(P<0.05)下降,即对重金属复合污染耐性较弱外,其余12种表现出对复合污染有较强的耐性。黄蜀葵在Cd一甲胺磷联合作用下的耐性研究表明,Cd与甲胺磷对黄蜀葵且对幼苗期根伸长的影响较发芽的影响大。对Cd与甲胺磷的联合效应分析表明Cd和甲胺磷存在拮抗作用,同时这种联合作用则是更多地依赖于Cd而非甲胺磷。

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The effect of C-12(6+) heavy ions bombardment on mutagenesis in Salvia splendens Ker-Gawl. was studied. Dose-response studies indicated that there was a peak of malformation frequency of S. splendens at 200 Gy. Abnormal leaf mutants of the bileaf, trileaf and tetraleaf conglutination were selected. Meanwhile, a bicolor flower chimera with dark red and fresh red flower was isolated in M1 generation of S. splendens. Random amplified polymorphic DNA (RAPD) analysis demonstrated that DNA variations existed among the wild-type, fresh and dark red flower shoots of the chimera. The dark red flower shoots of the chimera were conserved and cultivated at a large-scale through micropropagation. MS supplemented with 2.0 mg/L BA and 0.3 mg/L NAA was the optimal medium in which the maximum proliferation ratio (5.2-fold) and rooting rate (88%) were achieved after 6 weeks. Our findings provide an important method to improve the ornamental quality of S. splendens.

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A "ciganinha", cientificamente conhecida como Memora peregrina (Miers) Sandwith (Bignoniaceae), presente em diversas áreas de cerrado do Brasil Central, vem sendo um sério problema como invasora de pastagens cultivadas, em especial, quando estas já se encontram em adiantado estado de degradação. Nunes (1999) descreve-a como um arbusto, com ramos semilenhosos, entouceirado, ereto, que atinge a altura entre 100 e 150 centímetros. Apresenta inflorescências vistosas com flores amarelas semelhantes às do ipê-amarelo, o que contribuía para que, até recentemente, fosse catalogada apenas como planta ornamental (LORENZI; SOUZA, 1995). O principal período de florada ocorre na primavera e no verão, embora a presença de flores pode ser observada, praticamente, em qualquer época do ano. Sua reprodução se dá por sementes aladas, contidas em camadas sobrepostas no interior de uma cápsula com aspecto de uma longa vagem e, também, por processo vegetativo. Esse último ocorre pela ativação de gemas latentes presentes no caule, tanto em sua parte aérea quanto na subterrânea, em resposta ao seu eventual fracionamento ou quando este sofre lesões de qualquer natureza, especialmente por tratos mecânicos. Pouco se conhece sobre M. peregrina, porque mesmo em pastagens com gramíneas nativas e/ou naturalizadas, como Paspalum notatum (grama batatais ou mato-grosso), Melinis minutiflora (capimgordura) ou Hyparrhenia rufa (capim-jaraguá), manejadas há décadas com roçadeiras ou fogo, essa planta não é considerada problema. A ciganinha só assumiu o status de praga anos depois da implantação de pastagens cultivadas com uso de arados, grades de aração e subsoladores, sendo, em muitos casos, indicadora de pastagens degradadas ou em processo de degradação.

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A Embrapa Mandioca e Fruticultura Tropical instituiu há poucos anos atrás, os ?Dias dos Produtos? pesquisados pelo Centro. A data escolhida para a comemoração do ?Dia do Abacaxi? foi 04 de novembro. Isso porque foi nessa data que o navegador genovês, Cristóvão Colombo, em uma de suas históricas viagens, aportou na ilha de Guadalupe, e lá encontrou o abacaxi sendo cultivado pelos nativos. Impressionado pela beleza e forma da planta, pelo aroma e sabor do fruto, coletou alguns exemplares e os levou para a Europa, onde esse fruto teve grande aceitação. Em 2007, a comemoração do ?Dia do Abacaxi? foi adiada e ocorreu no dia 10/12/2007 à tarde, e também teve uma programação diferente, da qual constou, além da confraternização informal de praxe, uma sessão técnica composta de um painel. Nesse painel foram apresentadas quatro palestras referentes a alguns dos impactos e avanços obtidos pela Equipe Técnica de Abacaxi /ETA, da Unidade, ao longo de sua existência. Os temas das palestras versaram sobre o VI Simpósio Internacional de Abacaxi (pela primeira vez realizado no continente sulamericano e, mais especificamente, no Brasil); fitossanidade (fusariose) e produção integrada (com destaque para o Tocantins); melhoramento genético (híbridos resistentes e herança da resistência); usos alternativos do abacaxi (como ornamental, flor de corte, de vaso e de jardim); e aspectos econômicos e de mercado (peso médio do fruto brasileiro e posição do Brasil no mercado internacional). As palestras foram apresentadas, respectivamente, pelos pesquisadores Domingo Haroldo Reinhardt (coordenador do simpósio), Aristóteles Pires de Matos, José Renato Santos Cabral, Janay dos Santos-Serejo, Fernanda Vidigal Duarte Souza e Clóvis Oliveira de Almeida.

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O mercado de plantas ornamentais tropicais tem crescido mundialmente nos ultimos anos, havendo uma demanda constante por novas espécies e variedades. A Embrapa Mandioca e Fruticultura Tropical, localiza da em Cruz das Almas, BA, possui uma coleção (banco de gemoplasma) de cerca de 400 acessos de bananeiras, incluindo algumas espécies com características ornamentais que já são comercializadas, como a Musa omata que apresenta frutos de coloração verde e coração (inflorescência masculina) de coloração rosa-violáceo, e a Musa velutina que apresenta frutos rosados com pilosidade na casca e coração pequeno também de coloração rosada. Entretanto, apessar desse valor ornamental, ambas as espécies são suscetíveis ao mal-do-Panamá, tornando-se necessária a exploração da variabilidade genética existente para selecionar ou gerar genótipos resistentes e que possam ser explorados no mercado de flores tropicais.

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Todas as cultivares de abacaxi cujo interesse é o fruto, pertencem à espécie Ananas comosus var. comosus. Alguns clones de Ananas comosus var. erectifolius, Ananas comosus var. ananassoides e Ananas comosus var. bractetus são cultivados para produção de fibra ou para fins omamentais. Recentemente, houve grande incremento nestas formas de utilização.As principais características desejadas em uma cultivar de abacaxi são: crescimento rápido; folhas curtas, largas e com bordas sem espinhos; boa produção de mudas; fruto bem conformado, casca amarela; polpa amarela ou alaranjada, fime mas não fibrosa, teor de açúcar elevado, acidez moderada; coroa média a pequena. Associadas a estas características, procura-se ainda cultivares que produzam frutos de boa qualidade, que proporcionem altos rendimentos e que sejam resistentes e/ou tolerantes às principais pragas e doenças que ocorrem nos locais de plantio.