983 resultados para Ginger Cultivation


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为了研究开垦和放牧对内蒙古半干旱草原生态系统蒸发散的影响,我们以内蒙古锡林郭勒盟多伦县的草地和农田以及锡林浩特围封草地和退化草地为实验样地,利用涡度协方差技术对四个样地2006-2007年的蒸发散和微气象因子进行连续测定,探讨开垦和放牧对内蒙古半干旱草原生态系统蒸发散的影响及其驱动机制。同时利用稳定同位素技术区分多伦半干旱草原生态系统蒸发散的组分,初步探讨生态系统蒸发散各组分的变化特征及其驱动因子。 在观测的两年里,四个生态系统的年蒸发散接近或超过了年降雨量。在较湿润年份(2006年)的生长季(5-9月),开垦使得半干旱草原的蒸发散降低了15%,而在较干旱年份(2007年)降低了7%。放牧在2006年生长季期间使草原生态系统蒸发散降低了13%,而在2007年生长季里,围封草地和退化草地的蒸发散没有显著性差异。开垦和放牧造成的土壤含水量显著下降是生态系统蒸发散降低的最主要的原因。此外,农田开垦改变了植被的种类和物候特征,缩短了植物的生长期(农作物的生长期主要是6-8月,而草地的生长季一般为5-9月),是造成农田整个生长季的蒸发散比草地低的另一个原因。干旱年份降雨量少、土壤含水量低,限制了植被的生长,降低了冠层导度,从而导致了植物蒸腾的下降。另一方面,在干旱年份,开垦和放牧增加了草原生态系统蒸发散对土壤含水量变化的敏感性,表明未来降雨格局的变化不仅直接通过影响土壤含水量来改变蒸发散,而且会影响蒸发散和土壤含水量之间的相关性。 通过研究生态系统对不同强度和不同时间降雨的响应表明,> 3 mm的降雨会增加内蒙古半干旱草原生态系统的土壤含水量和蒸发散,对内蒙古半干旱草原生态系统关键过程有效。雨后1-2天蒸发散达到峰值,之后下降。多数大的降雨事件后,农田和退化草地蒸发散峰值比相对应的草地高,之后下降的也快,这与植被的生长状况、凋落物的量和地面的裸露程度有关。雨后土壤含水量和蒸发散的变化与降雨事件的大小呈正相关的关系,并且蒸发散的变化与土壤含水量的变化有显著的线性相关性,说明了土壤含水量是影响蒸发散变化的主要因子。土壤含水量初始值和干旱期的长短会影响内蒙古半干旱草原生态系统蒸发散对降雨的响应。土壤含水量初始值低会增强蒸发散对降雨的响应,而土壤含水量初始值高时,蒸发散对降雨的响应会下降。干旱期长会增强蒸发散对降雨的瞬时响应。围封草地由于有凋落物的缓冲和保水作用,未来降雨强度的增加会促进围封草原植被的生长;而退化草地地表裸露,对大的降雨事件缓冲作用小,地表径流和土壤蒸发强烈,不利于保水和植被的生长。因此,未来极端降雨事件频率的增加和干旱期的延长势必会对半干旱草原生态系统产生影响,尤其对退化草地产生不利影响。 为了进一步了解蒸发散组分的变化规律及其驱动因子,我们利用稳定同位素与微气象技术相结合的方法,区分半干旱草原生态系统蒸发散的组分。区分结果表明,在2006年和2007年整个生长季期间,植物蒸腾均为蒸发散的主要形式,在2006年和2007年生长季期间植物蒸腾占蒸发散的比例分别为88%和73%。影响植物蒸腾的因子主要是净辐射、大气相对湿度、土壤含水量和叶面积指数;影响蒸发的因子主要是大气相对湿度、土壤含水量和风速;而影响蒸发散的因子主要是净辐射、大气相对湿度、土壤含水量和风速,说明了这些水分流失过程受到不同环境因子的驱动。此外,我们根据一个简单的模型把同位素方法区分的蒸发散组分外推到整个生长季,结果表明,在2006年和2007年整个生长季蒸腾与蒸发散的比例高,并且蒸腾与降雨量的比例高,由此说明,半干旱草原生态系统植被能够有效地利用水分,雨水利用效率高。生态系统总初级生产力(GPP)与植物蒸腾(T)存在明显的正相关关系,从5-8月,生态系统水分利用效率(GPP/T)逐渐升高。 我们的研究结果表明:人类的活动如开垦和放牧通过改变植被类型、土壤持水能力和蒸发散对土壤含水量的响应,降低了草原生态系统的蒸发散,增加了生态系统蒸发散对降雨响应的敏感性,不利于土壤的保水和植被对水分的利用。半干旱草原生态系统蒸发散组分的稳定同位素技术区分,为进一步从新的角度探讨土地利用方式的改变对草原生态系统蒸发散影响的生理机制提供了可能。

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Freshwater animals are of importance in the economy of most countries. In recent years the scientific cultivation of freshwater fish for food has been spreading throughout South-East Asia and the Far-East. New and useful species of fish have been introduced into many countries including Ceylon where the older system of trapping any variety of fish that is available is being replaced by scientifically planned management with a view to increasing the production of good quality fish. Considerable quantities of food mainly in the form of fish are being taken from our freshwaters, providing a cheap source of much needed protein in the diet of the villager. More recently large quantities of freshwater fish are being consumed by the urban population.

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The results of experiments conducted on a pond dyke (655m²) in the Wastewater Aquaculture Division of the Central Institute of Freshwater Aquaculture, Rahara, during 1992-93 for maximising production through optimum utilisation of resources are communicated. Round the year intensive cultivation of okra (Abelmoschus esculentus), amaranth (Amaranthus gangeticus and A. viridus), water-bind weed (Ipomea aquatica), Indian spinach (Basella rubra), radish (Raphanus sativum), amaranth (Amaranthus viridis), cauliflower (Brassica oleracia var. votrytis), cabbage (Brassica oleracia var. capitota) and papaya (Carica papaya) was undertaken using the treated sewage water from fish ponds for irrigation. The pond dyke yielded 5,626.5 kg vegetable which worked out to 85.9 tons per ha per year. Multiple cropping with these vegetables excluding papaya on a 460 m² dyke recorded a production of 4,926.5 kg at the rate of 107.1t per ha/yr. An improved yearly net return of about 35% over investment could be achieved through the selection of highly productive and pest resistant vegetable crops of longer duration for integration into the system. Introduction of this type of integrated farming would enhance the overall productivity and returns from farming.

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本研究通过对玉簪属植物的组织培养,发现以腋芽、花序、试管苗的叶片为外植体,均可达到迅速繁殖的目的,但对于不同的玉簪品种来说,所能采用的外植体的种类又不尽相同:对于非嵌合体玉簪品种,以腋芽、花序、试管苗的叶片作外植体都可以;而对于嵌合体玉簪品种,如果以花序或试管苗的叶片为外植体,通过诱导不定芽进行快繁,在所得的试管苗中,超过50%的个体失去斑叶特性,这在实际生产中是不可行的,如果以腋芽为外植体,所得试管苗中多于95%的可保持原有嵌合体特征,故为理想的外植体。 在以腋芽为外植体的离体培养中,取嵌合玉簪品种H. ‘Francee’和H. ‘Ground Master’的芽作材料,通过对试验结果的分析、比较,选出了合适的繁殖培养基:MS + BA0.5mg/L + NAA0.5mg/L + KH2PO4150mg/L + 水解乳蛋白500mg/L + 蔗糖30g/L + 琼脂 5.6g/L,其可提高腋芽分化率,达到了快速繁殖的目的,此外,该培养基还可保持原来的生长势,降低斑叶特性分离比;同时选出了生根培养基:MS + IAA1mg/L + 蔗糖30g/L + 琼脂5.6g/L。 以花葶为外植体的试验,证实了此种方式仅适合非嵌合体玉簪的快速繁殖。 在以叶片为外植体的研究中,取了嵌合体品种H. ‘Francee’、H. ‘Ground Master’、H. ‘Gold Standard’、H. ‘Color Glory’和H. ‘Little Ming’的再生叶征作材料,通过对试验结果的分析、比较、观察到在培养基:MS + BA4mg/L + NAA0.1mg/L + 蔗糖 30g/L + 琼脂 5.6g/L上只有芽的形成,培养基:MS + BA0.4mg/L + NAA0.4mg/L + 蔗糖 30g/L + 琼脂 5.6g/L则利于根的发生,而培养基:MS + BA4mg/L + NAA0.4mg/L + 蔗糖 30g/L + 琼脂 5.6g/L促进根或(和)不定芽的产生,则因品种的不同而变化,另外还发现,经诱导不定芽途径所得到的试管苗,仅少于5%的个体保持斑叶特性,所以不可用于嵌合体玉簪的组织培养,但可快速繁殖非嵌合体玉簪。

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The present study deals with the chemical, algal and faunal characteristics of the stream system at Horton Plains, the highest plains in Ceylon (altitude 2'225 m). The cultivation of seed potatoes and subsequent use of fertilizers have caused extensive silting and severe eutrophication of the stream systems. Since there are no indigenous fish, the trout Salmo gairdnerii has been introduced and it is the only fish found in these streams. The commonest fauna in the streams are crabs (Paratelphusa sp.), shrimps (Caridimr sp.), Simulium sp. and Chironomus sp. Their increase in number is probably correlated with increase in organic and detritus matter. The most important food items of the trout are the crabs living abundantly in the stream, insect larvae and terrestrial insects were also commonly found in the guts. Records of stocking and taking of trout in the Horton plains streams have shown that now less trout are taken relatively to the numbers stocked. This decrease may be possibly due to the eutrophication of the stream and also due to the possible use of pollutants in connection with the cultivation of seed potatoes.

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目的 从体外培养成熟囊胚中分离并鉴定猕猴胚胎干细胞(embryonic stem cell , ES cell) 。方法 猕猴卵母细 胞经体外成熟培养、体外受精和早期胚胎体外成熟培养后,获得猕猴囊胚。当囊胚由透明带自然孵出后,用细玻璃针剥离 囊胚中的内细胞团(inner cell mass , ICM) 并与饲养细胞进行共培养。由ICM分离,培养并鉴定胚胎干细胞集落。结果 由 4 只FSH 超排猕猴中共取得92 个处于GV 期的猕猴卵母细胞,选取其中的22 个用HECM210 培养基培养后,获得6 个高质 量的囊胚,由此6 个囊胚中分离得到3 个内细胞团,并由此最终获得1 株猕猴ES 细胞,即RS5 细胞。RS5 细胞具高比例核P 质比,核仁多,其细胞集落边缘平整,其内各单个细胞清晰。经约5 个月的连续传代后,仍保持了正常二倍体的核型,其染 色体数目为42 条。碱性磷酸酶细胞组织化学染色为阳性,说明RS5 细胞为未分化态的胚胎干细胞。经高密度和长时间 培养后,RS5 细胞可进一步分化为多种类型细胞。结论 RS5 细胞株具有自我更新能力和多分化潜能,属于胚胎干细胞。

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Lobster analogues were prepared with lobster base flavour (paste),h lobster cook water (whole lobster omogenate:water, 1:1 and 1:0.5) and lobster meat mince. In another experiment, different combinations of ginger-garlic paste and lobster base flavour, i.e., 1:3, 1:4, 1:6, 3:3, 3:4, 3:6, 5:3, 5:4 and 5:6 were added to the lobster analogue paste. It was observed that lobster analogues prepared with lobster base flavour (paste) are suitable organoleptically. The combination of ginger garlic paste and lobster base flavour in the ratio of 3:4 was found to be suitable organoleptically. Lobster analogues coloured with annatto seed colour at 1:2 (annatto seed:water) concentration had high values for the colour attribute as compared to orange-red synthetic colour, beetroot colour, caramel colour and paprika colour. It was observed that come-up-time to achieve a temperature of850°C was 28 minutes with a processing period of 11 minutes.

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The evolutionary process of converting low-lying paddy fields into fish farms and its impact on agrarian communities in some selected areas of Mymensingh district were studied. This study was conducted through participatory rural appraisal (PRA) covering 12 villages from each of selected upazillas viz. Fulpur and Haluaghat of Mymensing [sic] district. A total of 12 PRA sessions were conducted where 90 farmers participated during 29 July to 26 August 2004. It is seen that the use of low-lying paddy fields was mostly confined to Broadcast Aman (B. Aman) rice production until 1960s. With the introduction of modern rice farming technology, the farmers started to produce Boro rice in Rabi season and B. Aman rice in Kharif season. With the passage of time, aquaculture technologies have been evolved and the farmers realized that fish farming is more profitable than rice cultivation, and then they started to utilize their paddy fields for alternate rice-fish farming and rice-cum-fish farming. Now a days, aquaculture based crop production system is in practice in more than 25% of the low-lying paddy fields. Conversion of rice fields in to fish ponds has brought up a change in the livelihood patterns of the rural farmers. The areas where the farmers involved themselves in the new production systems were fingerling collection, transportation and marketing of fry and fingerlings. During 1960s to 1970s, a few people used to culture fish in the permanent ponds for their own consumption, the species produced were rohu, catla, mrigal, ghainna, long whiskered catfish, freshwater shark (boal), snake head (shol) etc. Small fishes like climbing perch, stinging catfish, walking catfish, barb, minnows etc. were available in the rice fields during monsoon season. In 1980s to mid 1990s, some rice fields were converted into fish ponds and the people started to produce fish for commercial purposes. When rice-fish farming became profitable, a large number of people started converting their rice fields in to rice-fish culture ponds. Culture of some exotic fishes like silver carp, tilapia, grass carp, silver barb etc. also started in the paddy fields. Higher income from fish farming contributed positively in improving the housing, sanitation and education system in the study areas. It is seen that the medium and medium high lands were only used for alternate rice fish farming. The net income was high in any fish based cropping system that motivated the farmers to introduce fish based cropping system in the low-lying inland areas. As a result, the regional as well as communal income disparities occurred. However, the extraction of ground water became common during the dry period as the water was used for both rice and fish farming. Mass conversion of paddy fields into rice-fish culture ponds caused water logging in the study areas. In most cases, the participated farmers mentioned that they could be easily benefited by producing fish with T. Aman or only fish during the monsoon season. They agreed that this was an impressive technology to them and they could generate employment opportunities throughout the year. Finally, the social, economic and technical problems which are acting as constraints to rapid expansion of fish production system were reported from the interviewee.

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Aim: To study the pharmacokinetics of sifuvirtide, a novel anti-human immunodeficiency virus (HIV) peptide, in monkeys and to compare the inhibitory concentrations of sifuvirtide and enfuvirtide on HIV-1-infected-cell fusion. Methods: Monkeys received 1.2 mg/kg iv or sc of sifuvirtide. An on-line solid-phase extraction procedure combined with liquid chromatography tandem mass spectrometry (SPELC/MS/MS) was established and applied to determine the concentration of sifuvirtide in monkey plasma. A four-I-127 iodinated peptide was used as an internal standard. Fifty percent inhibitory concentration (IC50) of sifuvirtide on cell fusion was determined by co-cultivation assay. Results: The assay was validated with good precision and accuracy. The calibration curve for sifuvirtide in plasma was linear over a range of 4.88-5000 mu g/L, with correlation coefficients above 0.9923. After iv or sc administration, the observed peak concentrations of sifuvirtide were 10626 +/- 2886 mu g/L and 528 +/- 191 mu g/L, and the terminal elimination half-lives (T,12) were 6.3 +/- 0.9 h and 5.5 +/- 1.0 h, respectively. After sc, T-max was 0.25-2 h, and the absolute bioavailability was 49% +/- 13%. Sifuvirtide inhibited the syncytium formation between HIV-1 chronically infected cells and uninfected cells with an IC50 of 0.33 mu g/L. Conclusion: An on-line SPE-LC/MS/MS approach was established for peptide pharmacokinetic studies. Sifuvirtide was rapidly absorbed subcutaneously into the blood circulation. The T-1/2 of sifuvirtide was remarkably longer than that of its analog, enfuvirtide, reported in healthy monkeys and it conferred a long-term plasma concentration level which was higher than its IC50 in vitro.

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Background: Various evolutionary models have been proposed to interpret the fate of paralogous duplicates, which provides substrates on which evolution selection could act. In particular, domestication, as a special selection, has played important role in crop cultivation with divergence of many genes controlling important agronomic traits. Recent studies have indicated that a pair of duplicate genes was often sub-functionalized from their ancestral functions held by the parental genes. We previously demonstrated that the rice cell-wall invertase (CWI) gene GIF1 that plays an important role in the grain-filling process was most likely subjected to domestication selection in the promoter region. Here, we report that GIF1 and another CWI gene OsCIN1 constitute a pair of duplicate genes with differentiated expression and function through independent selection. Results: Through synteny analysis, we show that GIF1 and another cell-wall invertase gene OsCIN1 were paralogues derived from a segmental duplication originated during genome duplication of grasses. Results based on analyses of population genetics and gene phylogenetic tree of 25 cultivars and 25 wild rice sequences demonstrated that OsCIN1 was also artificially selected during rice domestication with a fixed mutation in the coding region, in contrast to GIF1 that was selected in the promoter region. GIF1 and OsCIN1 have evolved into different expression patterns and probable different kinetics parameters of enzymatic activity with the latter displaying less enzymatic activity. Overexpression of GIF1 and OsCIN1 also resulted in different phenotypes, suggesting that OsCIN1 might regulate other unrecognized biological process. Conclusion: How gene duplication and divergence contribute to genetic novelty and morphological adaptation has been an interesting issue to geneticists and biologists. Our discovery that the duplicated pair of GIF1 and OsCIN1 has experiencedsub-functionalization implies that selection could act independently on each duplicate towards different functional specificity, which provides a vivid example for evolution of genetic novelties in a model crop. Our results also further support the established hypothesis that gene duplication with sub-functionalization could be one solution for genetic adaptive conflict.

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Temperature effect on the pathogenicity of selected Edwardsiella tarda V-1 strain to Japanese eel, Anguilla japonica was investigated. To evaluate the effects of both pathogen incubation temperature and fish cultivation temperature on pathogen pathogenicity a two-factor design was conducted. E. tarda was incubated at 15, 20, 25, 30 and 37±1°C, and the fish (mean weight: 100g) were reared at 15, 20, 25 and 28±1°C respectively. The fish reared at different temperatures were infected with the E. tarda incubated at different temperatures. The results of a 4-day LD50 test showed that temperature significantly affected the pathogenicity of E. tarda (p<0.01) and the interaction between the two factors was also significant (p<0.01). For fish reared at 20°C the pathogenicity of E. tarda was the highest at 30°C of pathogen incubation. When the fish rearing temperature was raised to 25 and 28°C, the pathogenicity of E. tarda incubated at all temperatures increased. Isolation testing demonstrated results similar to those of LD50. The selected isolate was virulent to eel, but pathogenicity varied with temperature.

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抚仙金线鲃(Sinocyclocheilus tingi)是抚仙湖的特有种.2009年3-4月,有4次繁殖试验取得了成功.先后试验了40尾雌鱼和20尾雄鱼,成功催产19尾雌鱼和15尾雄鱼,分别占雌雄鱼的47.5%和75.0%.获得鱼卵25 547粒,并实施干法受精.有16810粒受精,平均受精率为65.8%.孵化出鱼苗约6040尾,平均孵化率为23.6%.经过20目的饲养,仔鱼存活3 056尾,存活率为50.6%.抚仙金线鲃较低的催产率,可能是生殖功能紊乱所致:但也不排除是人工营造的条件离其自然环境需求尚有距离.要使抚仙金线鲃成为鱼鱇<鱼良>白鱼(Anabarilius grahami)之后又一当地特色养殖鱼种,突破其人工繁殖瓶颈,培育高品质鱼苗是必由之路.突破其人工繁殖,还可为研究抚仙金线鲃的生活史和保护该物种免于灭绝奠定良好基础.

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利用稀释法结台平板分离培养法将采自滇池水华中的铜绿微囊藻进行了成功的 分离纯化对比纯化培养前后,发现纯化后该藻的生长速度明显加快,密度大为提高,约为纯化前 的5倍用乙醇乙醚混合液剐该藻作预处理后,破坏了其胶质被.再经常规方法提取总DNA,其得 率提高3 4倍

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Live 'agiis' have been proven to be a good feed for shrimp for the past ten years by polyculture fish farmers in the province of Capiz, in the island of Panay, west central Philippines. A brief account is given of culture and feeding operations. Its cultivation period is short and seeds are readily available. It can reduce dependence on trash fish which is now getting to be scarce; it also seems much cheaper. Perhaps this fast-growing tiny bivalve can be scientifically investigated by students of aquaculture as feed for other commercial aquaculture species. Its scientific identification can be a good start.

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In Cambodia, fish provide a major source of animal protein for rural households. Capture fisheries have declined and aquaculture has been identified as playing an important role in food and nutritional security and rural income generation. In 2011, WorldFish, in partnership with the Stung Treng Fishery Administration Cantonment and the Culture and Environment Preservation Association, aimed at improving the uptake of small-scale aquaculture by communities with limited experience in fish culture in Stung Treng Province in northeast Cambodia. The system was given the name “WISH ponds,” derived from the combination of the words "water" and "fish" to reflect the integration of fish cultivation with water for storage and vegetable growing. It was targeted towards households with limited space to construct large aquaculture ponds, such as peri-urban households. The study indicated that WISH ponds can create an important learning platform for communities to address challenges associated with small-scale aquaculture development by using scientific data generated and owned by the participants. Results from this 2011 study provided important insights into the challenges and constraints for introducing small-scale aquaculture into rural households in Cambodia. In mid-2013, WorldFish won a Feed the Future Partnering for Innovation grant, funded by the United States Agency for International Development, to build upon its successful engagement with communities in northeast Cambodia where WISH ponds had already been introduced and investigate scaling this technology to establish more WISH ponds in these communities.