991 resultados para Green revolution


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The paper traced the historical development of fisheries development in Nigeria. The paper was further discussed under the following sub-headings:- Ten years development plan 1945-1954, First National Development Plan 1962-1968, Second National Development Plan 1970-1974, Third and fourth National Development Plans. Several of the government programmes rolled out to enhance fisheries development are discussed, such as National accelerated fish production programme, operation feed the nation, the Green Revolution and structural adjustment Era. The paper confirmed that the past twenty years have witnessed phenomenal growth in Fisheries Development in Nigeria. However, decline has been noticed in the area of local fish production. This, has been due to a number of factors some of which are: prohibitive price of spare parts and fishing inputs, the increasing price of automatic gas oil.

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Despite the expenditure of huge amounts of money and human effort, the Green Revolution has largely failed to benefit the vast majority of the rural poor in Africa: those smallholding farmers who sell little, if any, of what they grow and rely almost entirely upon natural soil fertility, rainfall and traditional broodstock and seed varieties. New approaches on food production and income generation in the rural areas must be found if this sector of agricultural community is to be assisted. Integrated resources management (IRM) in general, and integrated agriculture-aquaculture (IAA) in particular, may offer some solutions in cases where the classical methods of improving farm output have failed and/or been unsustainable.

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株高是农作物的重要农艺性状之一,适度矮化有利于农作物的耐肥、抗倒、高产等。20世纪50年代,以日本的赤小麦为矮源的半矮秆小麦的培育和推广,使得世界粮食产量显著增长,被誉为“绿色革命”。迄今为止,已报到的麦类矮秆、半矮秆基因已达70多个,但由于某些矮源极度矮化或者矮化的同时伴随不利的农艺性状,使得真正运用于育种实践的矮源较少。因此,发掘和鉴定新的控制麦类作物株高的基因,开展株高基因定位、克隆及作用机理等方面的研究,对实现麦类作物株高的定向改良,具有重要的理论意义和应用价值。簇毛麦(Dasypyrum villosum,2n=14,VV)是禾本科簇毛麦属一年生二倍体异花授粉植物,为栽培小麦的近缘属。本课题组在不同来源的簇毛麦杂交后代中发现了一株自然突变产生的矮秆突变体。观察分析了该突变体的生物学特性,对矮秆性状进行了遗传分析,对茎节细胞长度、花粉的活力进行了细胞学观察,考察了该突变体内源赤霉素含量及不同浓度外施赤霉素对突变体的作用,分析了赤霉素生物合成途径中的内根贝壳杉烯氧化酶(KO)和赤霉素20氧化酶(GA20ox)的转录水平,对赤霉素20氧化酶和赤霉素3-β羟化酶(GA3ox)进行了克隆和序列分析,并对GA20ox进行了原核表达和表达的组织特异性研究。主要研究结果如下:1. 该突变体与对照植株在苗期无差异,在拔节后期才表现出植株矮小,相对对照植株,节间伸长明显受到抑制,叶鞘长度基本不变。在成熟期,对照植株的平均株高为110cm,而突变株的平均株高为32cm,仅为对照植株的1/3 左右。除了株高变矮以外,在成熟后期,突变株还表现一定程度的早衰和雄性不育。I2-KI染色法观察花粉活力结果表明,对照植株花粉90%以上都是有活力的,而突变植株的花粉仅20%左右有活力。2. 突变株与对照植株的杂交F1代均表现正常株高,表明该突变性状为隐性突变。F1代植株相互授粉得到的168株F2代植株中,株高出现分离,正常株高(株高高于80cm)与矮秆植株(株高矮于40cm)的株数比为130:38,经卡方检验,其分离比符合3:1的分离比,因此推测该突变体属于单基因的隐性突变。3. 用ELISA方法检测突变株和对照植株的幼嫩种子中内源性生物活性赤霉素(GA1+3)含量,结果表明突变株的赤霉素含量为36 ng/ml,而对照植株的赤霉素含量为900 ng/ml。对突变株外施赤霉素,发现矮秆突变株的株高和花粉育性均可得到恢复。这些结果表明该突变株为赤霉素缺陷型突变。4. 用荧光定量PCR方法比较突变株与对照植株中内根贝壳杉烯氧化酶和赤霉素20氧化酶的转录水平,结果表明突变株的KO转录水平比对照植株分别提高了6倍(苗期)和16倍(成熟期),突变株的GA20ox转录水平与对照植株在苗期无明显差异,在成熟期突变株较对照植株则提高了10倍左右。这些结果表明该矮秆突变体与赤霉素的生物合成途径密切相关,而且极有可能在赤霉素的生物合成途径早期就发生了改变。5. 以簇毛麦总基因组为模板,同源克隆了GenBank登录号为EU142950,RT-PCR分离克隆了簇毛麦的GA3ox基因cDNA全长序列,分析结果表明该cDNA全长1206bp,含完整编码区1104bp,推测该序列编码蛋白含368个氨基酸残基,分子量为40.063KD,等电点为6.27。预测的氨基酸序列含有双加氧酶的活性结构,在酶活性中心2个Fe离子结合的氨基酸残基非常保守。该序列与小麦、大麦和水稻的GA3ox基因一致性分别为98%、96%、86%。基因组序列与cDNA序列在外显子部分一致,在478-715bp和879-1019bp处分别含238bp和140bp的内含子。6. 通过RT-PCR技术克隆了簇毛麦的GA20ox基因全长,命名为DvGA20ox,GenBank登录号为EU142949。该基因全长1080个碱基,编码359个氨基酸,具有典型的植物GA20ox基因结构。该基因编码的蛋白质与小麦、大麦、黑麦草等GA20ox蛋白的同源性分别为98%,97% 和91%。该序列重组到原核表达载体pET-32a(+)上,将获得的重组子pET-32a(+)-DvGA20ox转化大肠杆菌BL21pLysS后用IPTG进行诱导表达。SDS-PAGE分析表明,DvGA20ox基因在大肠杆菌中获得了高效表达,融合蛋白分子量为55kDa。定量PCR分析表明,该基因在簇毛麦不同器官中的表达差异明显:叶片中表达水平最高,根部表达水平次之,茎部和穗中表达较弱。在外施赤霉素后,该基因的表达水平在两小时以后急剧下降,表明该基因的表达受自身的反馈调节。本研究结果认为,(1)该簇毛麦矮秆突变体为单基因的隐性突变;(2)该矮秆突变体为赤霉素敏感突变,内源赤霉素含量检测表明突变体的内源性赤霉素含量仅为对照植株的1/30;(3)荧光定量PCR结果表明突变株的赤霉素生物合成途径的关键酶基因表达水平比对照植株高,而且突变植株的赤霉素生物合成改变很可能发生在赤霉素生物合成途径的早期;(4)GA20ox有表达的组织特异性,且受到自身产物的反馈调节。 Plant height is an impotrant agronomic trait of triticeae crops.Semi-dwarf cropcultivars, including those of wheat, maize and rice, have significantly increased grainproduction that has been known as “green revolution”. The new dwarf varieties couldraise the harvest Index at the expense of straw biomass, and, at the sametime, improvelodging resistance and responsiveness to nitrogen fertilizer. Moreover, dwarf traits ofplant are crucial for elucidating mechanisms for plant growth and development aswell. In many plant species, various dwarf mutants have been isolated and theirmodles of inheritance and physiology also have been widely investigated.The causesfor their dwarf phenotypes were found to be associated with plant hormones,especially, gibberellins GAs.Dasypyrum villosum Candargy (syn.Haynaldia villosa) is a cross-pollinating,diploid (2n = 2x = 14) annual species that belongs to the tribe Triticeae. It is native toSouthern Europe and West Asia, especially the Caucasuses, and grows underconditions unfavorable to most cultivated crops. The genome of D. villosum,designated V by Sears, is considered an important donor of genes to wheat for improving powdery mildew resistance, take-all, eyespot, and plant and seed storageprotein content. A spontaneous dwarf mutant was found in D. villosum populations.The biological character and modles of inheritance of this dwarf mutant are studied.The cell length of stem cell is observed. The influence of extraneous gibberellin tothe dwarf mutant is also examined; the transcript level of key enzyme of gibberellinbiosynthesis pathway in mutant and control plants is compared. GA3ox and GA20oxare cloned and its expression pattern is researched.1. The dwarf mutant showed no difference with control plants at seedlingstage.At mature stage, the average height of control plants were 110cm and the dwarfplants were 33cm. The height of the mutant plant was only one third of the normalplants due to the shortened internodes. Cytology observation showed that theelongation of stem epidermal and the parenchyma cells were reduced. The dwarfmutant also shows partly male sterile. Pollen viability test indicates that more than80% of the pollen of the mutant is not viable.2. The inheritance modle of this dwarf mutant is studied. All The F1 plantsshowed normal phenotype indicating that the dwarfism is controlled by recessivealleles. Among the 168 F2 plants, there are 130 normal plants and 30 dwarf plants, thesegregation proportion accord with Mendel’s 3:1 segregation. We therefore proposethat this dwarf phenotype is controlled by a single recessive gene.3. Quantitative analyses of endogenous GA1+3 in the young seeds indicated thatthe content of GA1+3 was 36ng/ml in mutant plants and 900ng/ml in normal plants.The endogenous bioactive GA1+3 in mutant plants are only about 1/30 of that innormal plants. In addition, exogenously supplied GA3 could considerably restore themutant plant to normal phenotype. These results showed that this mutant wasdefective in the GA biosynthesis.4. More than ten enzymes are involved in GA biosynthesis. KO catalyzes thefirst cytochrome P450-mediated step in the gibberellin biosynthetic pathway and themutant of KO lead to a gibberellin-responsive dwarf mutant. GA20ox catalyze therate-limited steps so that their transcript level will influence the endogenous GAbiosynthesis and modifies plant architecture. The relative expression levels of genesencoding KO and GA20ox were quantified by real time PCR to assess whether thechanges in GA content correlated with the expression of GA metabolism genes andwhere the mutant occurred during the GA biosynthesis pathway. In mutant plants,the transcript levels of KO increased about 6-fold and 16-fold at the seedling stage and elongating stage respectively comparing with the normal plants. For theseedlings, there was no notable difference in the expression of GA20ox betweenmutant and normal plants. At the elongating stage, GA20ox transcript increased 10times in mutant plants, suggesting that the GA biosynthesis pathway in mutant plantshad changed from the early steps rather than the late steps.5. A full length cDNA of D. villosum gibberellin 3β-hydroxylase homology(designated as DvGA3ox) was isolated and consisted of 1206bp containing an openreading frame of 1104bp encoding 368 predicted amino acid residues. Identityanalysis showed that the gibberellin 3β-hydroxylase nucleotide sequence shared 98%,96% and 86% homology with that of wheat, barley and rice. The predicted peptidecontained the active-site Fe of known gibberellin 3β-hydroxylase and the regionhomologous to wheat, barley and Arabidopsis. The genomic clone of gibberellin3β-hydroxylase has two introns.6. The full-length cDNA of D. villosum gibberellin 20 oxidase (designated asDvGA20ox) was isolated and consisted of 1080-bp and encoded 359 amino acidresidues with a calculated mol wt of 42.46 KD. Comparative and bio-informaticsanalyses revealed that DvGA20ox had close similarity with GA20ox from otherspecies and contained a conserved LPWKET and NYYPXCQKP regions. Tissueexpression pattern analysis revealed DvGA20ox expressed in all the tissues that wereexamined and the highest expression of DvGA20ox in expanding leaves followed byroots. Heterologous expression of this cDNA clone in Escherichia coli gave a fusionprotein that about 55KD. Transcript levels of DvGA20ox dramatically reduced twohours after application of biologically active GA3, suggesting that the biosynthesis ofthis enzymes might be under feedback control.

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L’île de Java fait partie des régions les plus densément peuplées du monde. Lors de la seconde moitié du vingtième siècle, le gouvernement indonésien a instauré des politiques de transmigrations visant à décongestionner démographiquement l’île-maîtresse. Mais les objectifs de ce programme étaient multiples, visant notamment à fournir la main d’œuvre agricole, à bas prix, aux agro-industries afin de les inciter à s’installer dans les îles de la périphérie javanaise. La transition agraire a valorisé l’implantation de l’agriculture intensive à grande échelle. Ceci a contribué à l’exclusion progressive des paysans Javanais au sein des systèmes de production agricole, engendrant un changement de valeurs et d'aspirations au sein des communautés rurales. La transition agraire a ainsi contribué à accentuer la désagrarianisation des communautés rurales javanaises, se traduisant en un immense surplus de main-d’œuvre dans les campagnes suite à la révolution verte qui a été entamée au cours de la décennie 1970. L’émergence d’un noyau d’entrepreneurs et les migrations de travailleurs sont au cœur des stratégies de résilience économique développées par les paysans javanais pour faire face aux impacts de la transition agraire. Les rapatriements de fonds qui découlent des migrations contribuent à la survie de certaines communautés rurales, dans lesquelles de nombreux membres passent le plus clair de leur temps à l’extérieur du village.

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La búsqueda de los Estados por mitigar su dependencia energética de las fuentes fósiles, ha traído consigo la búsqueda de energías alternativas, desencadenando en el uso y producción de biocombustibles. A su vez, la producción de estos últimos a través de cultivos transgénicos ha ido cobrando importancia en el escenario internacional. Esta opción se ha considerado como una salida al dilema de utilización de tierras "Biocombustible vs. Alimentos". En este contexto, el caso de Argentina, como uno de los mayores productores de cultivos transgénicos del mundo, entre los cuales se destaca la soja, se analiza en esta investigación por ser importante para determinar cuál es el impacto de los biocombustibles producidos a través de cultivos transgénicos en la seguridad alimentaria de la población.

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The Global Environment Facility co-financed Soil Organic Carbon (GEFSOC) Project developed a comprehensive modelling system for predicting soil organic carbon (SOC) stocks and changes over time. This research is an effort to predict SOC stocks and changes for the Indian, Indo-Gangetic Plains (IGP), an area with a predominantly rice (Oryza sativa) - wheat (Triticum aestivum) cropping system, using the GEFSOC Modelling System and to compare output with stocks generated using mapping approaches based on soil survey data. The GEFSOC Modelling System predicts an estimated SOC stock for the IGP, India of 1.27, 1.32 and 1.27 Pg for 1990, 2000 and 2030, respectively, in the top 20 cm of soil. The SOC stock using a mapping approach based on soil survey data was 0.66 and 0.88 Pg for 1980 and 2000, respectively. The SOC stock estimated using the GEFSOC Modelling System is higher than the stock estimated using the mapping approach. This is due to the fact that while the GEFSOC System accounts for variation in crop input data (crop management), the soil mapping approach only considers regional variation in soil texture and wetness. The trend of overall change in the modelled SOC stock estimates shows that the IGP, India may have reached an equilibrium following 30-40 years of the Green Revolution. This can be seen in the SOC stock change rates. Various different estimation methods show SOC stocks of 0.57-1.44 Pg C for the study area. The trend of overall change in C stock assessed from the soil survey data indicates that the soils of the IGP, India may store a projected 1.1 Pg of C in 2030. (C) 2007 Elsevier B.V. All rights reserved.

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This study examines peasant family farming from an agroecological perspective. It intends to analyze the changes resulting from the transition from conventional to agro-ecological agriculture in the daily practices of farmers articulated associated with the Network of Agroecological and Solidarity Farmers of the Curu and Aracatiaçu Valleys Territory, the locus of this empirical research, and a space which has highlighted the social dynamics of agroecological innovation, as well as articulating environmental exchanges and knowledge development. As a way to further that goal, we seek to identify the forms of social organization previously present in the daily lives of these subjects, in addition to grasping the determinants that lead or led them to adopt agroecology, noting the need to verify the forms of resistance, and the strategies adopted by farmers and how they articulate collectively. Through the historical and dialectical methods, we seek to take the implications of technical modernization of agriculture under the conditions of production and reproduction of peasants and thus situate the emergence of agroecology, a focus that is born as a counterpoint to conventional patterns of agricultural development based on the paradigm of the Green Revolution. We structured this study around the trajectory of agroecological farmers that developed and internalized agroecological practices, processes, and organizational forms. For the analysis, we used theoretical and methodological frameworks from literature related to field research. The systematization and analysis of experiments revealed that agroecological transition is a broad process of change, not restricted to technical matters. We observed changes in production practices, diversification of production and feeding practices, ecological awareness, production autonomy, and organizations formed to face the challenges resulting from the imposition of the dominant agricultural development model that combines environmental degradation, land ownership concentration, and wealth concentration

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This article discusses the policy implications of agricultural modernization implemented by the military - after 1964. This policy, which became known as the Green Revolution, on the one hand contributed to the development of big business, but another caused serious social and environmental impacts. Currently, not only in Brazil but all over the world, have been in a great debate about the need to find alternatives to contain the problems caused to the environment resulting from the use of high technology in the field. One alternative proposed by several researchers is to replace fossil fuels by biofuels. As we believe that the error is in the current model of agricultural production based on mass production, which serves the major markets, the attention in this article, the need to develop an agricultural model designed for small property, with the use of family work and agroecology.

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This paper has two main objective the study of the productive space circuit of fertilizers in Brazil. For this, we study the company's operations Vale Fertilizers SA More specifically, the production and consumption of fertilizers in Brazil. In the current globalization the Brazilian countryside know new ways of doing (SANTOS, 1994). This, with less roughness, adopts the Green Revolution package, and introduces inputs to the soil, such as seeders, combines, tractors, herbicides, fungicides and fertilizers (Santos & Silveira, 2001). The examination of the Brazilian case as the agricultural modernization reveals the great vulnerability of modern agricultural regions in the face of globalizing modernization (Santos, 2000: 92). The places that receive capital reproduction of imperatives gain a new medium, is the formation of informational scientific technical means, are the bright spots corresponding to other places (Santos, 1994). Thus, the productive circuits are no longer confined to the environment, but establish connections with distant places (Santos, 1986; Frederick & CASTILLO, 2004). What's more, the policy is now made in the market (Santos, 2000, p.67) and the adoption by the Brazilian government's neoliberal policies, the Brazilian state-owned companies related to fertilizer production circuit are privatized, thereby Brazil makes It is further more dependent on inputs used in the field, including fertilizers

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Historically the evolution of the occupation of ararense territory was due to the expansion of agricultural activities. Such activities were intensified with the transformations engendered by the Green Revolution, increasing the exploitation, the area occupied by agriculture and the deforestation and consequent environmental degradation. Therefore the current reality of rural areas in Araras/SP has shown that part of agricultural practices made it does not guarantee the effectiveness of environmental legislation and the sustainability of farms. Considering the recently implemented environmental policies, such as Law nº 12.651 / 2012, better known as New Forest Code and Decree nº 8.235 / 2014 establishing a period of one year to rural property registered with the Rural Environmental Registry (CAR), as tools targeting to reduce environmental degradation and contribute to building a sustainable rural development. This work aims to analyze the dynamics of the rural municipality of Araras on the environmental situation in some rural properties and actions to be taken by the owners to the full compliance of its properties before the environmental public policy

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Government policies play a critical role in influencing market conditions, institutions and overall agricultural productivity. The thesis therefore looks into the history of agriculture development in India. Taking a political economy perspective, the historical account looks at significant institutional and technological innovations carried out in pre- independent and post independent India. It further focuses on the Green Revolution in Asia, as forty years after; the agricultural community still faces the task of addressing recurrent issue of food security amidst emerging challenges, such as climate change. It examines the Green Revolution that took place in India during the late 1960s and 70s in a historical perspective, identifying two factors of institutional change and political leadership. Climate change in agriculture development has become a major concern to farmers, researchers and policy makers alike. However, there is little knowledge on the farmers’ perception to climate change and to the extent they coincide with actual climatic data. Using a qualitative approach,it looks into the perceptions of the farmers in four villages in the states of Maharashtra and Andhra Pradesh. While exploring the adaptation strategies, the chapter looks into the dynamics of who can afford a particular technology and who cannot and what leads to a particular adaptation decision thus determining the adaptive capacity in water management. The final section looks into the devolution of authority for natural resource management to local user groups through the Water Users’ Associations as an important approach to overcome the long-standing challenges of centralized state bureaucracies in India. It addresses the knowledge gap of why some local user groups are able to overcome governance challenges such as elite capture, while others-that work under the design principles developed by Elinor Ostrom. It draws conclusions on how local leadership, can be promoted to facilitate participatory irrigation management.

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The Green Revolution has enabled Asian countries to boost their crop production enormously. However, Africa has not benefitted from this agricultural revolution since it did not consider local, but important crops grown in the continent. In addition to their versatile adaptation to extreme environmental conditions, African indigenous crops provide income for subsistence farmers and serve as staple food for the vast majority of low-income consumers. These crops, which are composed of cereals, legumes, vegetables and root crops, are commonly known as underutilized or orphan crops. Recently, some of these under-researched crops have received the attention of the national and international research community, and modern improvement techniques including diverse genetic and genomic tools have been applied in order to boost their productivity. The major bottlenecks affecting the productivity of these crops are unimproved genetic traits such as low yield and poor nutritional status and environmental factors such as drought, weeds and pests. Hence, an agricultural revolution is needed to increase food production of these under-researched crops in order to feed the ever-increasing population in Africa. Here, we present both the benefits and drawbacks of major African crops, the efforts being made to improve them, and suggestions for some future directions.

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Biofuel production, while highly contested, is supported by a number of policies worldwide. Ethiopia was among the first sub-Saharan countries to devise a biofuel policy strategy to guide the associated demand toward sustainable development. In this paper, I discuss Ethiopia’s biofuel policy from an interpretative research position using a frames approach and argue that useful insights can be obtained by paying more attention to national contexts and values represented in the debates on whether biofuel production can or will contribute to sustainable development. To this end, I was able to distinguish three major frames used in the Ethiopian debate on biofuels: an environmental rehabilitation frame, a green revolution frame and a legitimacy frame. The article concludes that actors advocating for frames related to social and human issues have difficulties entering the debate and forming alliances, and that those voices need to be included in order for Ethiopia to develop a sustainable biofuel sector.