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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

A concepção de fertilidade do agroecossistema: implicações teóricas e metodológicas da construção sócio-histórica de um conceito / The concept of fertility in agroecosystem: social and methodological implications of the socio-historical concept construction

Iamamoto, André Toshio Villela 04 October 2017 (has links)
Este trabalho visa realizar uma análise histórica da concepção de fertilidade na agricultura, observando de que forma a constituição deste conceito se relaciona com transformações históricas da sociedade, considerando a logica econômica que preside a agricultura industrial. Procura-se ressaltar as origens da formação do atual conceito de fertilidade e em que medida este foi influenciado pelo desenvolvimento da economia e da ciência moderna. Buscaremos também, ressaltar como as formas de produção que se colocam como contraponto a agricultura industrial entendem a questão da fertilidade, quais as alternativas por elas apresentadas ao manejo da fertilidade para os sistemas de produção ditos mais sustentáveis, e sobre que fundamentos epistemológicos e metodológicos elas se assentam. A fertilidade do solo na agricultura e, aqui, encarada como objeto de análise. Entendemos que o estudo do conceito de fertilidade, seu desenvolvimento teórico e as suas relações com a economia e a ciência apresenta a totalidade dos determinantes que moldaram e consolidaram a concepção cientifica e agronômica de fertilidade. O desenvolvimento histórico do conceito cientifico de \"fertilidade\" e suas implicações sócio-históricas espelham, portanto, um emaranhado de relações entre a economia, a sociedade e a ciência agronômica, que mostra, sob outro angulo, que ele próprio e o resultado de um processo histórico e social. Essa análise teórica possibilita elucidar caminhos analíticos para o entendimento e a construção de uma agricultura na perspectiva de uma sociedade mais justa e mais sustentável. Aparentemente pontual, a questão da fertilidade e aqui apreendida como a \"ponta de um iceberg\" de complexas e profundas relações entre o desenvolvimento da economia e da agronomia no âmbito da ciência, que contribuem para o agravamento das crises ambiental e civilizatória atuais ao validarem um conjunto de tecnologias que nada mais são do que a base instrumental de um modelo de desenvolvimento rural socialmente excludente e concentrador de riquezas. Complexa por natureza, a análise dessas inter-relações e das próprias crises acima citadas demandam um olhar crítico e que, sobretudo, supere as fronteiras disciplinares, enriquecendo o conhecimento com os achados de ciências especializadas numa perspectiva interdisciplinar. Dessa forma, o atual trabalho busca fazer uma leitura da fertilidade como um aspecto de destaque relacionado a crise da agricultura industrial através de um dialogo entre literaturas técnicas agronômicas e sociais. Esse dialogo interdisciplinar visa aumentar a amplitude de analise, e promover uma abordagem mais abrangente e historicamente situada sobre o tema em questão. / This project establishes a historical analysis of the soil fertility concept in agro-ecosystems, noticing how its constitution is related to historical transformations of society, considering the economic logic which presides the industrial agriculture. We highlight the origins of the formation of the current concept of fertility and to what extent, and how, this concept was influenced by the economy and modern science development. We also emphasize how the ways of production which arise in opposition to industrial agriculture face the issue of fertility, which alternatives to fertility management for more sustainable production systems they present, and which epistemological and methodological basis they have. Fertility is here understood as the \"top of the iceberg\" of deep and complex relations between economic and agronomic development in the scope of science that contribute to the worsening of the recent environment and civilization crisis by the validation of a set of technologies that are no more than the instrumental basis of rural social excluding development model which concentrates wealth. The analysis of the referred complexes interrelations demands a critic theoretical perspective in order to overcome the disciplinary boundaries and to enrich knowledge with the findings of the specialized science fields with an interdisciplinary perspective. Finally, the present project aims to highlight the fertility as a relevant aspect of the industrial agriculture crisis through a dialog between technical agronomic theory and social literature. This interdisciplinary dialog aims to promote a breadth and historical based analysis about this subject.
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Assessing the impacts of native freshwater mussels on nitrogen cycling microbial communities using metagenomics

Black, Ellen Marie 01 May 2018 (has links)
The Upper Mississippi River (UMR) basin contributes over 50,000 metric tons of nitrogen (N) to the Gulf of Mexico each year, resulting in a “dead zone” inhospitable to aquatic life. Land-applied N (fertilizer) in the corn-belt is attributed with a majority of the N-load reaching the Gulf and is difficult to treat as run-off is considered a non-point source of pollution (i.e. not from a pipe). One solution to this “grand challenge” of intercepting N pollution is utilizing filter-feeding organisms native to the UMR. Freshwater mussel (order Unionidae) assemblages collectively filter over 14 billion gallons of water, remove tons of biomass from overlying water, and sequester tons of N each day. Our previous research showed mussel excretions increased the sediment porewater concentrations of ammonium by 160%, and indirectly increased nitrate and nitrite by 40%, presumably from microbial degradation of ammonium. In response, the goal of this research was to characterize how mussels influenced microbial communities (microbiome) to determine the fate of N in UMR sediment. First, we used qPCR and non-targeted amplicon sequencing within sediment layers to identify the N-cycling microbiome and characterized microbial community changes attributable to freshwater mussels. qPCR identified that anaerobic ammonium oxidizing (anammox) bacteria were increased by a factor of 2.2 at 3 cm below the water-sediment interface when mussels were present. Amplicon sequencing of sediment at depths relevant to mussel burrowing (3 and 5 cm) showed that mussel presence reduced microbial species richness and diversity and indicated that sediment below mussels harbored distinct microbial communities. Furthermore, mussels increased the abundance of ammonia oxidizing bacteria (family Nitrosomonadaceae), nitrite oxidizing bacteria (genus Nitrospira), but decreased the abundance of ammonia oxidizing archaea (genus Candidatus Nitrososphaera), and microorganisms which couple denitrification with methane oxidation. These findings suggested that mussels may enhance microbial niches at the interface of oxic and anoxic conditions, presumably through excretion of N and burrowing activity. In response, we performed metagenomic shotgun sequencing to identify which genes of the microbiome were most impacted by mussels. We hypothesized that genes responsible for ammonia and nitrite oxidation would be greater in the sediment with mussel assemblages. We found the largest abundance of N-cycling genes were responsible for nitrate reduction and nitrite oxidation, which is corroborated by the high concentration of nitrates in UMR water. Linear discriminant analysis statistical analyses showed nitrification genes were most impacted by mussels, and this presented an opposing effect on genes responsible for producing nitrous oxide, a potent greenhouse gas. Further investigation showed an increased abundance of a novel organism capable of completely oxidizing ammonia to nitrate (Candidatus Nitrospira inopinata) and coexisted with metabolically flexible Nitrospira (sp. moscoviensis), likely enhancing both carbon and N-cycling. We demonstrated that native mussels harbor a unique niche for N-cycling microorganisms with large metabolic potentials to degrade mussel excretion products. Our findings suggest the ecosystem services of mussels extend beyond water filtration, and includes enhanced biogeochemical cycling of carbon, N, and reduces the potential for a potent microbially-produced greenhouse gas. Ultimately, this research could be used to advocate for mussel habitat restoration in the UMR to lessen the impacts of non-point pollution.
13

Comparing avifauna communities and bird functional diversity of forest and farmland in southwest Ethiopia

Engelen, Dries January 2012 (has links)
Worldwide degradation and conversion of tropical forests affects many species and their provided ecosystem services. Among them are birds, responsible for pollination, seed dispersal, pest control and scavenging. This study, conducted in southwest Ethiopia, compares species composition and bird functional diversity between forest and homegardens close to and far from forest, both in terms of species numbers and bird abundances. Point counts and mist netting were used to obtain data. While the former method detected more species, abundance data from the latter revealed patterns not observed by just comparing species numbers. I found that species diversity was lower in forest compared to gardens and that the species composition of both communities was significantly distinct. Whereas forest had more forest specialists, gardens held more forest visitors and species of open country. Close and far gardens did not differ in any aspect, except that abundances of forest generalist birds were somewhat higher close to forest. Regarding bird feeding guilds, I found that granivores and nectarivores were more numerous in gardens, while frugivores were more common in forest. Carnivores and omnivores showed no effect. Insectivore proportions were the same for forest and farmland, but their numbers (including those of all sub-guilds) were higher in gardens. The Ethiopian forest avifauna is poor in comparison with other Afromontane regions, lacking several, mostly insectivorous genera. This could be the result of an extinction after which its geographic isolation made recolonization difficult, especially for dispersal-limited understory species. Nonetheless, and despite their impoverished state, the results suggest that forest remnants are important for forest-dependent species, being a stronghold for forest specialists and supporting higher numbers of forest generalists in nearby gardens. However, future forest regrowth might be at stake with ongoing agricultural encroachment, because gardens hold fewer frugivores, especially forest specialists, which might affect seed dispersal. / Många arter påverkas negativt av avskogning och annan mänsklig påverkan på tropiska skogar, vilket också kan få konsekvenser för de ekosystemtjänster dessa arter levererar. En viktig artgrupp i detta avseende är fåglar, som kan ha betydelse för pollination, fröspridning, naturlig skadedjurskontroll och som asätare. Denna studie, utförd i sydvästra Etiopien, jämför artsammansättning och funktionell diversitet hos fåglar i skogar och trädgårdar både nära och långt ifrån skogen. Både antal arter och antal individer har undersökts. Data materialet bygger både på observationer från punktinventering och fåglar fångade med slöjnät. Med den första metoden noterade jag fler arter, medan abundansvärden från den andra metoden gjorde att jag såg mönster som inte syntes vid endast jämförelser av artrikedom. Jag fann att artrikedomen var lägre i skogen i jämförelse med trädgårdarna, men att artsammansättningen var signifikant skiljd däremellan. Skogarna hade fler skogsspecialister medan trädgårdarna hade fler arter från öppna marker och tillfälliga skogsbesökande arter. Trädgårdar som låg nära eller långt ifrån skogen skiljde sig inte på något sätt utom att individtätheten av skogsgeneralister var något högre i trädgårdar nära skogen. När det gäller uppdelningen av fåglarna utifrån vad de äter så fann jag att fröätande och nektarätande arter var vanligare i trädgårdar medan fruktätande arter var vanligare i skogen. Rovfåglar och allätare uppvisade inget tydligt mönster. Proportionen insektsätande fåglelarter var samma i skogen och trädgårdarna, men det absoluta antalet arter (inklusive alla olika underkategorier) var högre i trädgårdarna. Den etiopiska skogsfågelfaunan är artfattig i förhållande till andra bergstrakter i Afrika och saknar flera släkten av framförallt insektsätande fåglar. Detta skulle kunna bero på ett tidigare utdöende varefter en senare återkolonisering varit svår på grund av den geografiska isoleringen, speciellt för insektsätande fåglar som huvudsakligen finns i undervegetationen. Trots den relativa artfattigdomen så visar resultatet från min studie hursomhelst på att skogarna är viktiga för skogsberoende fåglar. Den största betydelsen har de för skogsspecialister där, men även genom en positiv effekt på abundansen av skogsgeneralister i närliggande trädgårdar. Dock kan framtida återväxt av skogar bli problematisk på grund av en pågående omvandling av skogar till trädgårdar, eftersom trädgårdar hyser färre fruktätande fåglar, vilket kan påverka fröspridning över landskapet. / Examining mismatches between management and the supply of ecosystem services in Ethiopian agroecosystems across scales in space and time
14

INNER BLUEGRASS AGRICULTURE: AN AGROECOLOGICAL PERSPECTIVE, 1850-1880

Patrick, Andrew Parker 01 January 2012 (has links)
This study examines agriculture in the Inner Bluegrass Region of Central Kentucky from 1850 to 1880. It utilizes an agroecological perspective, which interprets agriculture through the lens of ecology, to highlight the complex natural and cultural factors that combined to form one of the nation's most prosperous agricultural systems during the nineteenth century. Chapter One explores the agroecosytem Bluegrass farmers created and maintained, emphasizing dynamics in crop and livestock diversity and agricultural technology. Chapter Two examines the African-American labor force that played a key role in shaping the system, first as slaves and later as free men and women. Chapter Three addresses the cultural outlooks and institutions that influenced land use patterns, ranging from beliefs on proper methods of cultivation to voluntary organizations designed to facilitate market access. Through an examination of the various influences at work on the agricultural environment, the landscape emerges as a dynamic factor, rather than a passive backdrop, in Inner Bluegrass history.
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Η επίδραση των εισροών στην ποιότητα του εδάφους στο οροπέδιο της κοινότητας Ομαλών στη νήσο Κεφαλληνία

Βαγγελάτου, Πόλυ 13 July 2010 (has links)
Σκοπός της παρούσας εργασίας είναι η μελέτη της επίδρασης των εισροών στην ποιότητα του εδάφους των καλλιεργειών, στο οροπέδιο της κοινότητας Ομαλών στη νήσο Κεφαλληνία, μέσω της αξιοποίησης των στοιχείων που προκύπτουν από την δομή και την περιγραφή του συγκεκριμένου αγροτικού οικοσυστήματος. Η μελέτη έγινε σε βιολογικούς και συμβατικούς ελαιώνες και αμπελώνες και διήρκησε 1 χρόνο. Κατά την διάρκεια του χρόνου αυτού, πραγματοποιήθηκαν δειγματοληψίες από τα υπό μελέτη εδάφη και προσδιορίσθηκαν χημικές και βιολογικές ιδιότητες. Συγκεκριμένα προσδιορίστηκαν το pH, η Ικανότητα Ανταλλαγής Κατιόντων, η οργανική ουσία, η Ηλεκτρική αγωγιμότητα, ο φώσφορος, τα ανταλλάξιμα κατιόντα K, Na και Mg, το ολικό άζωτο, το βόριο τα νιτρικά και η εδαφική αναπνοή. Για την αξιοποίηση των αποτελεσμάτων των εδαφολογικών αναλύσεων ήταν απαραίτητη η γνώση των καλλιεργητικών πρακτικών που εφαρμόζονται στα αγροτεμάχια καθώς και οι ποσότητες των εισροών σε αυτά. Για το σκοπό αυτό πραγματοποιήθηκαν συνεντεύξεις σε αγρότες της περιοχής με την χρήση ερωτηματολογίων ανοιχτού τύπου. Από τα ερωτηματολόγια προέκυψε ότι η υψηλότερη ενεργειακή εισροή στο εδαφικό υποσύστημα είναι η κοπριά τόσο στην περίπτωση της βιολογικής καλλιέργειας όσο και συμβατικής καλλιέργειας ελιάς και αμπέλου. Η εντατική χρήση υψηλών ποσοτήτων κοπριάς συμβάλλει στην βελτίωση των χημικών και βιολογικών ιδιοτήτων του εδάφους αλλά εγκυμονεί κινδύνους για την ποιότητα του. / In the following research the effects of agroecosystem inputs on soil quality of crops at plateau Omala of Cephalonia island via the exploitation of elements that result through the study of the structure and the description of particular agroecosystem, were studied. The research had a duration of above 1 year, in which samplings from the soil and their chemical and biological attributes were not only realized but also evaluated concretely pH,Cation Exchange Capacity, organic matter, Electrical Conductivity, the phosphor, Exchangeable Cations K, Na and Mg, total N, NO3, the boron and the microbial rate, were measured. For the exploitation of results of soil analysis it was essential to have obtain knowledge of farming practices that is applied in the farmyards as well as the quantities of inputs. This aim was realised through interviews with farmers of the region with the use of open type questionnaires. The result of these questionnaires was that the higher energy input in the soil subsystem is manure. The intensive use of high quantities of manure contributes to the improvement of the chemical and biological attributes of soil but gestates dangers for soil quality.
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Bats, insects and pecans: habitat use and ecosystem services of insectivorous bats in a pecan agroecosystem in central Texas

Braun de Torrez, Elizabeth Claire 22 January 2016 (has links)
Comprehensive wildlife conservation strategies must include consideration of the agricultural matrix and its integration into the greater landscape. Bats are postulated to provide critical pest suppression services, but the effects of agricultural intensification on insectivorous bats are not clear. Few studies have thoroughly investigated the ecosystem services provided by bats due, in part, to limited understanding of species-specific habitat use in agricultural landscapes, difficulties in prey identification, and the challenge of quantifying the impact of bats on pest populations and crops. My dissertation integrates these components to describe ecological relationships between the insects and bats associated with a pecan agroecosystem in central Texas. Specifically, I focus on the predator-prey relationship between bats and the pecan nut casebearer moth (PNC), a devastating pest of pecans. I begin with a literature review of the ecosystem services of insectivorous bats and the data necessary to thoroughly evaluate these services. I then assess the potential factors influencing species composition and spatio-temporal distributions of bats within the pecan agroecosystem. My results demonstrate higher activity and diversity of bats within the pecan agroecosystem than in the surrounding landscape likely due to roosting opportunities, but species-specific and seasonal differences exist in the effects of management intensity. Next, I investigate direct interactions between bats and PNC by measuring prey consumption patterns. I found that five species of bats prey upon PNC moths during all three critical population peaks prior to insecticide application, but there is variability in consumption among species. Finally, I assess indirect interactions between bats and pecans, by evaluating the effect of bat predation risk on pecan damage by PNC larvae. A negative relationship between foraging activity by bats and both PNC moths and PNC larval damage to pecans provides evidence that bat predation has quantitative downstream effects. My results highlight the conservation value of the agricultural matrix for bats and the complexities of accurately documenting ecosystem services provided by free-ranging mobile organisms.
17

Sustentabilidade da caprinocultura na região do agreste paraibano. / Sustainability of caprinoculture in the region of agreste paraibano.

SILVA, Lenice. 09 October 2018 (has links)
Submitted by Maria Medeiros (maria.dilva1@ufcg.edu.br) on 2018-10-09T15:00:04Z No. of bitstreams: 1 LENICE SILVA - DISSERTAÇÃO (PPGRN) 2018.pdf: 1716487 bytes, checksum: 5ab6867163fdb29ffc164b11f5c6a772 (MD5) / Made available in DSpace on 2018-10-09T15:00:04Z (GMT). No. of bitstreams: 1 LENICE SILVA - DISSERTAÇÃO (PPGRN) 2018.pdf: 1716487 bytes, checksum: 5ab6867163fdb29ffc164b11f5c6a772 (MD5) Previous issue date: 2018-06 / O objetivo geral desta pesquisa foi avaliar a sustentabilidade da caprinocultura nos municípios de São João do Cariri e São José dos Cordeiros, estado da Paraíba, fazendo-se o uso da metodologia MESMIS. Na pesquisa foram realizadas visitas em 30 propriedades localizadas nos municípios supracitados, na região semiárida do Estado, nos meses de junho e julho de 2017, utilizando-se questionários semiestruturados junto ao público alvo, os produtores de caprinos. A metodologia adotada foi proposta pela ferramenta MESMIS, que permitiu avaliar a sustentabilidade dos agroecossistemas considerando aspectos: ambientais sociais e econômicos dos produtores e suas famílias que tem na caprinocultura, a principal atividade produtiva. Os dados obtidos foram analisados por meio da estatística de análise multivariada, submetidas à distribuição de frequência, análise de correspondência múltipla e de agrupamento. A utilização da metodologia MESMIS permitiu a utilização de indicadores que possibilitaram a avaliação da sustentabilidade dos agroecossistemas desenvolvidos nas unidades de produção em caráter familiar que foram o objeto de estudo dessa pesquisa a partir de uma visão holística considerando fatores relacionados não só as questões sociais como também ambientais e econômicas. Possibilitando a observação dos pontos positivos e negativos da atividade produtiva estudada e as medidas tomadas no intuito de promover um desenvolvimento mais sustentável da mesma. A partir dos fatores elencados em cada uma das três categorias, foi possível observar que mesmo diante da escassez hídrica vivenciada pelos os municípios estudados, nos últimos anos, os produtores vêm caminhando em direção da sustentabilidade dos agroecossistemas, a partir da superação das limitações que se apresentaram em cada categoria analisada. / The general objective of this research was to evaluate the sustainability of goat breeding in the municipalities of São João do Cariri and São José dos Cordeiros, state of Paraíba, using the MESMIS methodology. In the survey, visits were made to 30 properties located in the aforementioned municipalities, in the semi-arid region of the State, in the months of June and July 2017, using semi-structured questionnaires with the target public, goat producers. The methodology adopted was proposed by the MESMIS tool, which allowed the evaluation of the sustainability of agroecosystems considering the social and economic environmental aspects of the producers and their families that have the main production activity in goat farming. The data obtained were analyzed using multivariate analysis statistics, submitted to frequency distribution, multiple correspondence analysis and clustering. The use of the MESMIS methodology allowed the use of indicators that enabled the evaluation of the sustainability of the agroecosystems developed in the family units that were the object of study of this research from a holistic view considering factors related not only to social issues but also environmental and economic conditions. Making it possible to observe the positive and negative points of the productive activity studied and the measures taken in order to promote a more sustainable development of the same. Based on the factors listed in each of the three categories, it was possible to observe that even in the face of the water scarcity experienced by the studied municipalities, in recent years, farmers have been moving toward the sustainability of agroecosystems, by overcoming the limitations that presented in each category analyzed.
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Sistema de produção orgânico de milho (Zea mays L.), feijão (Phaseolus vulgaris L.) e mandioca (Manihot sculenta Crantz) consorciados com soqueira de cana-deaçúcar (Sacharum spp.) / Production system of organic maize (Zea mays L.), bean (Phaseolus vulgaris L.) and manioc (Manihot esculenta CRANTZ), intercropped with ratoon-cane (Sacharum spp.)

Apolari, João Paulo 22 June 2009 (has links)
Made available in DSpace on 2016-06-02T18:57:22Z (GMT). No. of bitstreams: 1 2612.pdf: 3727772 bytes, checksum: a07242a151d45c71c3e73e29300d6100 (MD5) Previous issue date: 2009-06-22 / Greater stability of an agroecosystem can be achieved through the consortium system under organic management, becomes an important environmental factor to a highest stability of the agroecosystem. The objective was to study a system of production for organic crops of maize (Zea mays L., cv. BR 106), bean (Phaseolus vulgaris L., cultivar IAC Pérola) and manioc (Manihot esculenta CRANTZ, cv. IAC 15), intercropped with ratoon-cane (Saccharum spp.). The experimental design was a randomized, with eight (8) treatments and four (4) replicates, as follows: T1 ratoon-cane without intercropping (control), T2: ratooncane and intercropping of maize (cs + mi), T3: ratoon-cane and intercropping of bean (cs + fe); T4: ratoon-cane and intercropping of manioc (cs + ma), T5: ratooncane and intercrops of maize and bean (cs + mi + fe) T6: ratoon-cane and intercrops of maize and manioc (cs + mi + ma); T7 ratoon-cane and intercrops of bean and manioc (cs + f + ma), T8: ratoon-cane and intercrops of maize, bean and manioc (cs + mi + fe + ma). Productivity of the crops, the gross income obtained and the residual biomass waste of maize, beans and manioc, in each system were evaluated. For the conditions of the experiment, the treatment intercropping maize (T2) showed the best results on productivity of green maize ears (kg/ha), production of biomass (kg/ha) and gross income (R$/ha). The alternative of the consortium of distinct crops with ratoon-cane proves to be an effective technique that, from the viewpoint of agroecology, becomes an important tool for preserving and maintaining the agroecosystem, besides providing alternative foods and additional income to the farmer. / Maior estabilidade do agroecossistema pode ser obtida através do plantio consorciado, o qual, sob manejo orgânico, torna-se um fator ambiental que pode ser utilizado como complemento a outras técnicas de cultivo. O objetivo foi estudar um sistema de produção orgânico de milho (Zea mays L., variedade BR 106), feijão (Phaseolus vulgaris L., cultivar IAC Pérola) e mandioca (Manihot esculenta CRANTZ, variedade IAC 15) consorciados com soqueiras da cultura de cana-deaçúcar (Saccharum spp.). O delineamento estatístico utilizado foi o de blocos casualizados, contando com oito (8) tratamentos e quatro (4) repetições, sendo T1: cana-soca sem cultura intercalar (testemunha); T2: cana-soca e cultura intercalar de milho (cs+mi); T3: cana-soca e cultura intercalar de feijão (cs+fe); T4: cana-soca e cultura intercalar de mandioca (cs+ma); T5: cana-soca e culturas intercalares de milho e feijão (cs+mi+fe); T6: cana-soca e culturas intercalares de milho e mandioca (cs+mi+ma); T7: cana-soca e culturas intercalares de feijão e mandioca (cs+fe+ma); T8: cana-soca e culturas intercalares de milho, feijão e mandioca (cs+mi+fe+ma). Avaliou-se a produtividade das culturas, a renda bruta estimada e a biomassa residual de milho, feijão e mandioca, em cada sistema. Para as condições do experimento, o tratamento cultura intercalar de milho (T2) apresentou os melhores resultados quanto à produtividade de espigas verdes (kg/ha), a produção de biomassa (kg/ha) e renda bruta estimada (R$/ha). A alternativa do consórcio de diferentes culturas com soqueira de cana-de-açúcar demonstra ser uma técnica eficiente que, sob a ótica da agroecologia, se torna uma ferramenta importante na preservação e manutenção do agroecossistema, além de proporcionar alimento e renda adicional para o agricultor familiar.
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Sistema de produção orgânico de milho (Zea mays L.), feijão (Phaseolus vulgaris L.) e mandioca (Manihot esculenta Crantz) consorciados com soqueira de cana-deaçúcar (Sacharum spp.) / Production system of organic maize (Zea mays L.), bean (Phaseolus vulgaris L.) and manioc (Manihot esculenta Crantz), intercropped with ratoon-cane (Sacharum spp.)

Apolari, João Paulo 22 June 2009 (has links)
Made available in DSpace on 2016-06-02T18:57:29Z (GMT). No. of bitstreams: 1 2612.pdf: 3727772 bytes, checksum: a07242a151d45c71c3e73e29300d6100 (MD5) Previous issue date: 2009-06-22 / Greater stability of an agroecosystem can be achieved through the consortium system under organic management, becomes an important environmental factor to a highest stability of the agroecosystem. The objective was to study a system of production for organic crops of maize (Zea mays L., cv. BR 106), bean (Phaseolus vulgaris L., cultivar IAC Pérola) and manioc (Manihot esculenta CRANTZ, cv. IAC 15), intercropped with ratoon-cane (Saccharum spp.). The experimental design was a randomized, with eight (8) treatments and four (4) replicates, as follows: T1 ratoon-cane without intercropping (control), T2: ratooncane and intercropping of maize (cs + mi), T3: ratoon-cane and intercropping of bean (cs + fe); T4: ratoon-cane and intercropping of manioc (cs + ma), T5: ratooncane and intercrops of maize and bean (cs + mi + fe) T6: ratoon-cane and intercrops of maize and manioc (cs + mi + ma); T7 ratoon-cane and intercrops of bean and manioc (cs + f + ma), T8: ratoon-cane and intercrops of maize, bean and manioc (cs + mi + fe + ma). Productivity of the crops, the gross income obtained and the residual biomass waste of maize, beans and manioc, in each system were evaluated. For the conditions of the experiment, the treatment intercropping maize (T2) showed the best results on productivity of green maize ears (kg/ha), production of biomass (kg/ha) and gross income (R$/ha). The alternative of the consortium of distinct crops with ratoon-cane proves to be an effective technique that, from the viewpoint of agroecology, becomes an important tool for preserving and maintaining the agroecosystem, besides providing alternative foods and additional income to the farmer. / Maior estabilidade do agroecossistema pode ser obtida através do plantio consorciado, o qual, sob manejo orgânico, torna-se um fator ambiental que pode ser utilizado como complemento a outras técnicas de cultivo. O objetivo foi estudar um sistema de produção orgânico de milho (Zea mays L., variedade BR 106), feijão (Phaseolus vulgaris L., cultivar IAC Pérola) e mandioca (Manihot esculenta CRANTZ, variedade IAC 15) consorciados com soqueiras da cultura de cana-deaçúcar (Saccharum spp.). O delineamento estatístico utilizado foi o de blocos casualizados, contando com oito (8) tratamentos e quatro (4) repetições, sendo T1: cana-soca sem cultura intercalar (testemunha); T2: cana-soca e cultura intercalar de milho (cs+mi); T3: cana-soca e cultura intercalar de feijão (cs+fe); T4: cana-soca e cultura intercalar de mandioca (cs+ma); T5: cana-soca e culturas intercalares de milho e feijão (cs+mi+fe); T6: cana-soca e culturas intercalares de milho e mandioca (cs+mi+ma); T7: cana-soca e culturas intercalares de feijão e mandioca (cs+fe+ma); T8: cana-soca e culturas intercalares de milho, feijão e mandioca (cs+mi+fe+ma). Avaliou-se a produtividade das culturas, a renda bruta estimada e a biomassa residual de milho, feijão e mandioca, em cada sistema. Para as condições do experimento, o tratamento cultura intercalar de milho (T2) apresentou os melhores resultados quanto à produtividade de espigas verdes (kg/ha), a produção de biomassa (kg/ha) e renda bruta estimada (R$/ha). A alternativa do consórcio de diferentes culturas com soqueira de cana-de-açúcar demonstra ser uma técnica eficiente que, sob a ótica da agroecologia, se torna uma ferramenta importante na preservação e manutenção do agroecossistema, além de proporcionar alimento e renda adicional para o agricultor familiar.
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Ocorrência de parasitoides associados a pragas do milho (Zea mays L.) cultivado em diferentes sistemas de produção

Silva, Rafael Braga da 27 March 2013 (has links)
Made available in DSpace on 2016-06-02T19:29:56Z (GMT). No. of bitstreams: 1 5149.pdf: 19234114 bytes, checksum: 746c92ee6c0b11a82da926b06b913747 (MD5) Previous issue date: 2013-03-27 / Financiadora de Estudos e Projetos / The aim of this study was to determine the occurrence of parasitoids of the major pests of maize (Zea mays L.) cultivated in different production systems. The experiment was conducted at the Embrapa Milho e Sorgo, in Sete Lagoas, State of Minas Gerais, Brazil, in conventional production systems, organic, organic intercropped with beans (Phaseolus vulgaris L.) and organic exclusive. In the collections of plants made in conventional maize and organic maize were only obtained larvae of Spodoptera frugiperda, with the emergence of the parasitoids Archytas sp.1, Archytas sp.2, Cotesia sp., Dolichozele koebelei, Eiphosoma laphygmae, Eiphosoma sp.1, Eiphosoma sp.2, Euplectrus sp., Exasticolus sp. nov., Hyphantrophaga sp. and Winthemia sp. Cremastinae species and Ophion flavidus occurred in organic maize; Campoletis sp. in conventional maize. In the ear of conventional maize and ear of organic maize were obtained larvae of Diatraea saccharalis, Dichomeris famulata, Euxesta spp., Helicoverpa zea, Megaselia seticauda and S. frugiperda. Megaselia seticauda was first reported in the ears of maize in Brazil. The parasitoids obtained from the ears of conventional maize and organic maize in S. frugiperda were: Hyphantrophaga sp. occurring in both areas, Glyptapanteles sp. only in the conventional maize and Microcharops sp. only in the organic maize, for H. zea in the organic maize parasitized larvae were not obtained, in the conventional maize, occurred the parasitoids Aleiodes sp. and Copidosoma sp. Apanteles sp. and Phanerotoma sp. occurred on D. famulata in the conventional maize and organic maize; Chelonus (Microchelonus) sp. nov., Microcharops sp. and Perilampus sp. occurred only in the conventional maize. Apsilophrys sp. occurred only in organic maize. These are the first records of Apanteles sp., Chelonus (Microchelonus) sp. nov., Microcharops sp., Perilampus sp. and Phanerotoma sp. on D. famulata. In Euxesta spp. in the organic maize were not obtained larvaes killed by parasitoids in the conventional maize on Euxesta spp. occurred the parasitoid Dettmeria sp. About D. saccharalis and M. seticauda, there were not obtained parasitoids. In the collections of stalks of conventional maize and organic maize, there was a prevalence of D. saccharalis, S. frugiperda occurred only in conventional maize. There were not observed larvaes of S. frugiperda killed by parasitoids, but for D. saccharalis, occurred, in two areas, the parasitoid Lixophaga sp. In the collections of plants, in the organic maize exclusive and organic maize intercropped with beans, the parasitoids obtained from the larvae of S. frugiperda were Archytas sp., Campoletis sp., Cotesia sp., D. koebelei, E. laphygmae, Eiphosoma sp.1, Eiphosoma sp.2, Eiphosoma sp.3, Eiphosoma sp.4, Eiphosoma sp.5, Glyptapanteles sp., Microcharops sp. and O. flavidus. The parasitoids Aprostocetus sp., Chelonus insularis, Colpotrochia sp. nov. and Ichneumoninae were observed only in the exclusive organic maize, while Apanteles sp. and Eiphosoma sp.6 only in the organic maize intercropped with beans. From the pests of the ear of maize collected in the organic maize exclusive and in the organic maize intercropped with beans occurred larvaes of D. famulata, Euxesta spp., H. zea, M. seticauda and S. frugiperda. From these only larvaes of H. zea and D. famulata were parasitized. The index of parasitism of H. zea by Archytas sp. was similar in both areas, the parasitoid of D. famulata, Apsilophrys sp. was observed in all samples of organic maize intercropped with beans, but it did not occur in any collection of the exclusive organic maize. In these samples were not obtained for parasitoids Euxesta spp., M. seticauda and S. frugiperda. In the collections of stalks in organic maize exclusive and organic maize intercropped with beans were obtained only larvaes of D. saccharalis without the occurrence of parasitoids. In both experiments the number of larvaes of the pests collected was low, new associations and new species of parasitoids reported represent the possibility of the exploitation of these natural enemies in the control of pests in the culture of maize. / O objetivo deste estudo foi determinar a ocorrência de parasitoides das principais pragas de milho (Zea mays L.) cultivado em diferentes sistemas de produção. O experimento foi conduzido na Embrapa Milho e Sorgo em Sete Lagoas, Minas Gerais (MG), Brasil, em sistemas de produção convencional, orgânico, orgânico consorciado com feijão (Phaseolus vulgaris L.) e orgânico solteiro. Nas coletas de plantas realizadas no milho convencional e no milho orgânico só foram obtidas larvas de Spodoptera frugiperda, com a emergência dos parasitoides Archytas sp.1, Archytas sp.2, Cotesia sp., Dolichozele koebelei, Eiphosoma laphygmae, Eiphosoma sp.1, Eiphosoma sp.2, Euplectrus sp., Exasticolus sp. nov., Hyphantrophaga sp. e Winthemia sp. Espécies de Cremastinae e Ophion flavidus ocorreram no milho orgânico; Campoletis sp., no milho convencional. Nas espigas de milho convencional e de milho orgânico foram obtidas larvas de Diatraea saccharalis, Dichomeris famulata, Euxesta spp., Helicoverpa zea, Megaselia seticauda e S. frugiperda. Megaselia seticauda foi registrada pela primeira vez em espigas de milho no Brasil. Os parasitoides obtidos das espigas no milho convencional e no milho orgânico em S. frugiperda foram: Hyphantrophaga sp. ocorrendo nas duas áreas; Glyptapanteles sp., apenas no milho convencional; e Microcharops sp., somente no milho orgânico; para H. zea no milho orgânico não foram obtidas larvas parasitadas, no milho convencional, ocorreram os parasitoides Aleiodes sp. e Copidosoma sp., Apanteles sp. e Phanerotoma sp. ocorreram sobre D. famulata no milho convencional e no milho orgânico; Chelonus (Microchelonus) sp. nov., Microcharops sp. e Perilampus sp. ocorreram apenas no milho convencional; Apsilophrys sp., ocorreu somente no milho orgânico. Esses são os primeiros registros de Apanteles sp., Chelonus (Microchelonus) sp. nov., Microcharops sp., Perilampus sp. e Phanerotoma sp. sobre D. famulata. Em Euxesta spp. no milho orgânico não foram obtidas larvas mortas por parasitoides, no milho convencional sobre Euxesta spp. ocorreu o parasitoide Dettmeria sp. Sobre D. saccharalis e M. seticauda, não foram obtidos parasitoides. Nas coletas de colmos em milho convencional e no milho orgânico, houve prevalência de D. saccharalis. Não foram observadas larvas de S. frugiperda mortas por parasitoides, já para D. saccharalis, ocorreu, nas duas áreas, o parasitoide Lixophaga sp. Nas coletas de plantas, no milho orgânico solteiro e no milho orgânico consorciado com feijão, os parasitoides obtidos das larvas de S. frugiperda foram Archytas sp., Campoletis sp., Cotesia sp., D. koebelei, E. laphygmae, Eiphosoma sp.1, Eiphosoma sp.2, Eiphosoma sp.3, Eiphosoma sp.4, Eiphosoma sp.5, Glyptapanteles sp., Microcharops sp. e O. flavidus. Já os parasitoides Aprostocetus sp., Chelonus insularis, Colpotrochia sp. nov. e Ichneumoninae foram observados somente no milho orgânico solteiro, enquanto Apanteles sp. e Eiphosoma sp.6 apenas no milho orgânico consorciado com feijão. Quanto às pragas da espiga coletadas no milho orgânico solteiro e no milho orgânico consorciado com feijão ocorreram larvas de D. famulata, Euxesta spp., H. zea, M. seticauda e S. frugiperda. Destas apenas larvas de H. zea e de D. famulata foram parasitadas. O índice de parasitismo de H. zea por Archytas sp. foi semelhante nas duas áreas; o parasitoide de D. famulata, Apsilophrys sp., foi observado em todas as coletas do milho orgânico consorciado com feijão, mas não ocorreu em nenhuma coleta do milho orgânico solteiro. Nessas coletas não foram obtidos parasitoides para Euxesta spp., M. seticauda e S. frugiperda. Nas coletas de colmos em milho orgânico solteiro e no milho orgânico consorciado com feijão foram obtidas apenas larvas de D. saccharalis sem a ocorrência de parasitoides. Nos dois experimentos o número de larvas das pragas coletadas foi baixo, as novas associações e as novas espécies de parasitoides relatadas representam a possibilidade de utilização desses inimigos naturais no controle de pragas na cultura do milho.

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