Made available in DSpace on 2014-06-11T19:28:28Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-11-01Bitstream added on 2014-06-13T19:16:24Z : No. of bitstreams: 1 santos_ep_me_jabo.pdf: 811104 bytes, checksum: bcd035d537d9aeb8084fc66fc53510f8 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Copercana / O arranquio, momento de grande importância na produção do amendoim, que se realizada de forma ineficiente pode representar em alguns casos perdas de até 30%. Considerando-se o curto período de tempo disponível para o cultivo do amendoim em áreas de reforma de canaviais, este trabalho teve por objetivo testar a hipótese de que é possível antecipar o arranquio mecanizado do amendoim, sem acarretar prejuízos ao produtor. Para tanto, realizou-se o arranquio do amendoim aos 120, 125, 130, 135 e 140 dias após a semeadura, sendo os resultados avaliados por análise estatística descritiva e multivariada, com uso de análise de variância, para as variáveis: porcentagem de maturação, teor de água das vagens e do solo, índice de cone, perdas no arranquio mecanizado e produtividade. A análise de variância indicou que o adiamento do arranquio de amendoim IAC runner 886 não está diretamente relacionado com o aumento da produtividade, e que as perdas no arranquio tendem a aumentar gradativamente com o aumento do tempo de permanência da cultura no campo, sendo que aos 135 dias após a semeadura, ocorre aumento expressivo destas perdas. A análise multivariada possibilitou analisar de forma conjunta a ação das variáveis, indicando que existe correlação inversa do índice de cone com a produtividade, e entre o teor de água do solo e das vagens com a maturação, além de evidenciar a correlação entre as perdas visíveis e invisíveis do arranquio / In the digging, moment of great importance in the production of peanuts, is conducted in an inefficient way, in some cases may represent losses of up to 30%. Considering the short time available for the cultivation of peanuts in sugarcane areas of reform, this study aimed to test the hypothesis that it is possible to anticipate the mechanical digging from peanuts without causing damage to the producer. Thus, it was carried out the digging the peanut at 120, 125, 130, 135 and 140 days after sowing, and the results were evaluated by multivariate and descriptive statistics analysis, using analysis of variance for the variables: percentage of maturity, water content of the pod and the soil, cone index, losses on the pull-off mechanized and productivity. Analysis of variance indicated that the postponement of the pull-off of the peanut IAC runner 886 is not directly related to increased productivity, and pull-off losses tend to increase gradually with the increase of residence time of the culture in the field, and that 135 days after sowing, there is significant increase in these losses. Multivariate analysis allowed to analyze jointly the action of the variables, indicating that there is an inverse correlation of cone index with productivity, and between the water content of soil and the pods with the maturation, and also highlights the correlation between visible and invisible losses of the digging

Thesis (MScAgric)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: ‘Triumph’ persimmon production in South Africa is export driven and the profitability of the industry is largely dependent on consumer demand and supermarket shelf space in the European market. In order to realise high returns, it is important to advance harvest maturity to attain early fruit that arrives on the market prior to European summer fruits. In addition, market feedback suggests that fruit picked during the second half of the harvesting period stores poorly and rapidly softens during shelf life. It is important to establish whether this is the case. The effect of paclobutrazol (PBZ) application rate on fruit maturity and keeping quality, return bloom and vegetative growth was investigated over two seasons. Advanced harvest maturity was attained at a compromise of reduced fruit storage quality and stunted growth with the severity of the compromise increasing with increasing PBZ application rate. To advance harvest maturity while maintaining acceptable keeping quality, PBZ application at 0.75 ml per plant is recommended although effects on harvest maturity will not persist into the subsequent season as found at higher application rates. Prohexadione-calcium (P-Ca) as an alternative for PBZ in advancing harvest maturity was evaluated over two seasons. A positive response to three foliar applications of P-Ca at 200 mg·L-1 was noticed in the first season. In the second season, a single application of P-Ca at 300 mg·L-1 two weeks before harvest significantly advanced harvest maturity. Due to the rapid metabolism of P-Ca in the plant, it is unlikely that growth in the subsequent season will be affected. Based on these results, the persimmon industry will undertake commercial trials in the 2012 season to further assess the efficacy of P-Ca application in advancing harvest maturity. The effect of various rest breaking agents (RBAs) on bud break, flowering, fruit maturity and quality as well as vegetative growth was assessed for one season. RBAs did not increase or advance bud break and flowering. Consequently, yield and harvest maturity were unaffected by the treatments. The ineffectiveness of the RBAs could be due to the low application rates used or the fulfilment of the chilling requirement prior to treatment application. An experiment was carried out to determine whether storability and shelf-life differ between “early” and “late” production areas in South Africa as well as between orchards within these areas. The data indicated that fruit colour is a good maturity parameter and indicator of fruit storability. However, “late” fruit were about 1 kg softer than “early” fruit at the same colour chart value. We therefore recommend that fruit from late regions are harvested at colour chart values of 5 and 6 (yellow-green) instead of 3 and 4. Fruit from “late” orchards as well as GA3-treated fruit with a colour chart value of 3 and less should be culled due to the high propensity (>20%) of these fruit to become soft during storage and shelf life. A delay in 1-MCP treatment and interruption of the cold chain considerably increased fruit softening during storage and shelf-life. Further research is required to verify this result. / AFRIKAANSE OPSOMMING: ‘Triumph’ persimmon produksie in Suid-Afrika is uitvoergedrewe en die winsgewendheid van die bedryf is grootliks afhanklik van verbruikervraag en supermark spasie in die Europese mark. Ten einde hoë pryse te realiseer, is dit belangrik om ʼn vroeë oes te verkry sodat vrugte voor die Europese somervrugte op die mark beland. Mark terugvoer dui verder daarop dat vrugte wat tydens die tweede helfte van die oesperiode gepluk word, swakker opberg en vinnig sag word gedurende op die rak. Dit is belangrik om vas te stel of hierdie waarneming juis is. Die effek van paklobutrazol (PBZ) toedieningshoeveelheid op vrugrypwording en - houvermoë, opvolgblom en vegetatiewe groei is oor twee seisoene ondersoek. Oesrypheid is vervroeg, maar tot nadeel van vrughouvermoë en vegetatiewe groei. Die omvang van die negatiewe effekte van PBZ het toegeneem met ʼn toename in toedieningshoeveelheid. Ten einde oesrypheid te vervroeg terwyl aanvaarbare houvermoë behou word, word toediening van PBZ teen 0.75 ml per plant aanbeveel alhoewel die effek op oesrypheid anders as die geval met hoër toedieningshoeveelhede nie in die opeenvolgende seisoen sal voortduur nie. Proheksadioon-kalsium (P-Ca) as alternatief tot PBZ om oesrypheid te vervroeg is oor twee seisoene gee-valueer. ʼn Positiewe effek op vrugrypwording is in die eerste seisoen verkry met drie blaartoedienings van P-Ca teen 200 mg·L-1. In die tweede seisoen is oesrypheid betekenisvol vervroeg deur ʼn enkel toediening van 300 mg·L-1 P-Ca ʼn maand voor oes. Vanweë hierdie resultate gaan die persimmonbedryf in die 2012 seisoen kommersiële proewe onderneem om die effektiwiteit van P-Ca om oes te vervroeg, verder te ondersoek. Die effek van verskeie rusbrekende middels (RBAs) op bot, blom, vrugrypheid, vrugkwaliteit en vegetatiewe groei is vir een seisoen ondersoek. RBAs het bot en blom vervroeg of vermeerder nie en het daarom ook geen effek op produksie en oesrypheid gehad nie. Die oneffektiwiteit van die RBAs kan moontlik toegeskryf word aan die lae toedieningsvlakke wat gebruik is of aan die kouebehoefte wat bevredig is voor toediening van RBAs. ʼn Eksperiment is gedoen om vas te stel of die opberging- en houvermoë van vrugte verskil tussen “vroeë” en “laat” produksieareas in Suid-Afrika en ook tussen boorde in hierdie areas. Die data dui daarop dat vrugkleur ʼn goeie rypheidsparameter en indikator van opbergingsvermoë is. Vrugte van laat areas was egter omtrent 1 kg sagter as vrugte van vroeë areas van dieselfde kleur. Ons beveel gevolglik aan dat vrugte van laat areas by ʼn kleurkaartwaarde van 5 tot 6 (geelgroen) geoes word eerder as by 3 tot 4. Vrugte van laat boorde sowel as vrugte wat met GA3 behandel is met ʼn kleurkaartwaarde van 3 en laer moet afgradeer word weens die hoë geneigdheid (>20%) van hierdie vrugte om sag te word tydens opberging en op die rak. Uitstel van 1-MCP behandeling en die onderbreking van die koueketting veroorsaak ʼn aansienlike toename in sagte vrugte tydens opberging en op die rak. Verdere navorsing word benodig om hierdie resultaat te verifieer.

Orientador: Rouverson Pereira da Silva / Coorientador: Antonio Sérgio Ferraudo / Banca: Denise Mahl / Banca: Carlos Eduardo Angeli Furlani / Resumo: O arranquio, momento de grande importância na produção do amendoim, que se realizada de forma ineficiente pode representar em alguns casos perdas de até 30%. Considerando-se o curto período de tempo disponível para o cultivo do amendoim em áreas de reforma de canaviais, este trabalho teve por objetivo testar a hipótese de que é possível antecipar o arranquio mecanizado do amendoim, sem acarretar prejuízos ao produtor. Para tanto, realizou-se o arranquio do amendoim aos 120, 125, 130, 135 e 140 dias após a semeadura, sendo os resultados avaliados por análise estatística descritiva e multivariada, com uso de análise de variância, para as variáveis: porcentagem de maturação, teor de água das vagens e do solo, índice de cone, perdas no arranquio mecanizado e produtividade. A análise de variância indicou que o adiamento do arranquio de amendoim IAC runner 886 não está diretamente relacionado com o aumento da produtividade, e que as perdas no arranquio tendem a aumentar gradativamente com o aumento do tempo de permanência da cultura no campo, sendo que aos 135 dias após a semeadura, ocorre aumento expressivo destas perdas. A análise multivariada possibilitou analisar de forma conjunta a ação das variáveis, indicando que existe correlação inversa do índice de cone com a produtividade, e entre o teor de água do solo e das vagens com a maturação, além de evidenciar a correlação entre as perdas visíveis e invisíveis do arranquio / Abstract: In the digging, moment of great importance in the production of peanuts, is conducted in an inefficient way, in some cases may represent losses of up to 30%. Considering the short time available for the cultivation of peanuts in sugarcane areas of reform, this study aimed to test the hypothesis that it is possible to anticipate the mechanical digging from peanuts without causing damage to the producer. Thus, it was carried out the digging the peanut at 120, 125, 130, 135 and 140 days after sowing, and the results were evaluated by multivariate and descriptive statistics analysis, using analysis of variance for the variables: percentage of maturity, water content of the pod and the soil, cone index, losses on the pull-off mechanized and productivity. Analysis of variance indicated that the postponement of the pull-off of the peanut IAC runner 886 is not directly related to increased productivity, and pull-off losses tend to increase gradually with the increase of residence time of the culture in the field, and that 135 days after sowing, there is significant increase in these losses. Multivariate analysis allowed to analyze jointly the action of the variables, indicating that there is an inverse correlation of cone index with productivity, and between the water content of soil and the pods with the maturation, and also highlights the correlation between visible and invisible losses of the digging / Mestre

Insect damage in stored maize is one of the major post-harvest losses occurring in developing countries, especially in sub-Saharan Africa. To reduce economic losses, separation of infested grains from clean ones is critical and requires detection of infestation in stored grains. This study aimed at developing a rapid non-destructive detection system with three goals; - the first goal was to investigate the acoustic behavior of internally feeding S. zeamais (Coleoptera: Curculionidae) in maize. The pests were monitored for peak activity and signal amplitudes. The study was performed in the morning, afternoon and night times for three consecutive days with an ultrasonic probe attached to acoustic emission detector. The average number of peaks above threshold in the morning, afternoon and night was significantly different and were 60, 2 and 31 counts/s, respectively (P-value < 0.01). The average maximum amplitude was also different: 2.5, 1 and 1.8V for morning, afternoon and night sessions, respectively. The signal frequencies ranged between 1 and 15 kHz with a peak around 7 kHz. The second goal was to design and develop an inexpensive acoustic device for the detection of S. zeamais in the stored maize. This device included a microphone, signal conditioning circuit and a microcontroller. The third goal was to test the prototype in both clean and infested maize. The device could be manufactured for $55 or less. The device has a noise level below 0.2V in clean maize, infestation amplitude up to 1V and about 93.3% correct detection performance in infected maize. / Master of Science

The release of genetically modified, herbicide tolerant canola (<I>Brassica napus</i> L.) genotypes in western Canada has increased interest in the persistence of volunteer canola. <i>B. napus</i> seed may be induced into secondary dormancy in the laboratory, however, little is known of the seedbank ecology and the role of secondary dormancy as a persistence mechanism in this species in the region. The objectives of this research were i) to determine seedbank additions at the time of harvest, ii) determine the role of secondary seed dormancy in seedbank persistence under different management systems, iii) determine the relative importance of factors contributing to secondary dormancy potential and iv) evaluate the role of abscisic acid (ABA) during secondary dormancy induction in <I>B. napus</i>. On farms, average seedbank additions during harvest were approximately 20 times the normal seeding rate of canola. High secondary seed dormancy potential prolonged seedbank persistence in fields, irrespective of tillage system. <I>B. napus</i> exhibited seedling recruitment of a typical summer annual weed where seedling recruitment was only observed in the spring. Seasonal seedling recruitment was the result of two fates: seed death in the shallow seedbank, irrespective of dormancy potential, and increased ungerminability in buried seeds which was related to secondary seed dormancy potential. Among the factors that contribute to secondary seed dormancy potential, genotype was of greatest significance. Seed size was of lesser importance, while the contributions of pre-harvest factors including seed maturity, year, and location were negligible in comparison. Differences in ABA synthesis and the response to ABA application were related to secondary seed dormancy potential and correlated well previous reports linking ABA to seed dormancy. Conclusions that emerge from this research are i) that on some farms, seedbank additions may be lowered by more diligent harvest practices, ii) seedbank persistence of <I>B. napus</i> may be reduced by growing low dormancy genotypes and avoiding seed burial for one year after seedbank establishment and iii) ABA + ABA-glucose ester (ABA-GE) and the ability of seeds to respond to ABA application after seed dormancy induction may potentially be used to identify seed dormancy potential in this species.

The release of genetically modified, herbicide tolerant canola (<I>Brassica napus</i> L.) genotypes in western Canada has increased interest in the persistence of volunteer canola. <i>B. napus</i> seed may be induced into secondary dormancy in the laboratory, however, little is known of the seedbank ecology and the role of secondary dormancy as a persistence mechanism in this species in the region. The objectives of this research were i) to determine seedbank additions at the time of harvest, ii) determine the role of secondary seed dormancy in seedbank persistence under different management systems, iii) determine the relative importance of factors contributing to secondary dormancy potential and iv) evaluate the role of abscisic acid (ABA) during secondary dormancy induction in <I>B. napus</i>. On farms, average seedbank additions during harvest were approximately 20 times the normal seeding rate of canola. High secondary seed dormancy potential prolonged seedbank persistence in fields, irrespective of tillage system. <I>B. napus</i> exhibited seedling recruitment of a typical summer annual weed where seedling recruitment was only observed in the spring. Seasonal seedling recruitment was the result of two fates: seed death in the shallow seedbank, irrespective of dormancy potential, and increased ungerminability in buried seeds which was related to secondary seed dormancy potential. Among the factors that contribute to secondary seed dormancy potential, genotype was of greatest significance. Seed size was of lesser importance, while the contributions of pre-harvest factors including seed maturity, year, and location were negligible in comparison. Differences in ABA synthesis and the response to ABA application were related to secondary seed dormancy potential and correlated well previous reports linking ABA to seed dormancy. Conclusions that emerge from this research are i) that on some farms, seedbank additions may be lowered by more diligent harvest practices, ii) seedbank persistence of <I>B. napus</i> may be reduced by growing low dormancy genotypes and avoiding seed burial for one year after seedbank establishment and iii) ABA + ABA-glucose ester (ABA-GE) and the ability of seeds to respond to ABA application after seed dormancy induction may potentially be used to identify seed dormancy potential in this species.

No description available.

A redução das perdas é de grande importância para estabilizar a oferta de alimentos ao longo da cadeia de suprimentos e fortalecer a segurança alimentar. O objetivo geral desta pesquisa foi realizar um diagnóstico detalhado sobre as perdas que ocorrem nas diversas atividades logísticas de soja e milho no Brasil, envolvendo a quantificação das perdas físicas, econômicas e ambientais acumuladas na cadeia de suprimentos de tais grãos e a identificação de estratégias e políticas públicas para mitiga-las, através da modelagem de programação matemática. Além disso, foi possível estruturar uma função de perdas na agrologística de grãos a partir de quatro variáveis: tipo de armazenagem, qualidade das vias rodoviárias, modalidade de transporte e canal de comercialização. As perdas totais na cadeia de suprimentos de soja e milho no ano de 2015 no Brasil atingiram o patamar de 2,381 milhões de toneladas, ou seja, algo em torno de 1,303% da produção, incorrendo em perdas econômicas decorrentes do custo de oportunidade com vendas perdidas e de gastos logísticos desnecessários na ordem de R$ 2,04 bilhões (US$ 610,78 milhões). Os cenários avaliados demonstram que a ampliação no uso da armazenagem dentro da fazenda, melhoria nas condições das rodovias brasileiras e das estradas que conectam as fazendas aos armazéns apresentam grande potencial para mitigação das perdas. Apesar da perda relativa de uma atividade logística assumir valor decimal, a perda acumulada ao longo da cadeia de suprimentos assume um valor global bastante considerável. Esse retrato enfatiza a necessidade de conscientização sobre as perdas visando fomentar políticas públicas e gestões eficientes para mitiga-las, dado as externalidades econômicas, ambientais e sociais geradas. / Reducing losses is of great importance in stabilizing the supply of food throughout the supply chain and strengthening food security. The general objective of this research was to perform a detailed diagnosis of the losses that occur in the many logistic activities of soybeans and maize in Brazil, involving the quantification of accumulated physical, economic and environmental losses in the supply chain of such grains and the identification of strategies and public policies to mitigate such losses through mathematical programming modeling. Besides, it was possible to structure a loss function of grains\' agrologistics in terms of four variables: type of storage, quality of roads, modality of transportation and marketing channel. Total losses in the soy and maize supply chain in 2015 in Brazil reached up to 2.381 million tons, or about 1.303% of production, incurring economic reductions due to the cost of loss (reduced sales and unnecessary logistical expenses for the handling of losses) in the order of R$ 2.04 billion (US$ 610.78 million). The evaluated scenarios show that the increase in the use of on-farm storage, the improvement in the conditions of the Brazilian highways and roads that connect the farms to the external warehouses present great potential to mitigate the losses. In spite the relative loss of a logistic activity takes on decimal value, the cumulative loss along the supply chain assumes a fairly considerable overall value. This reality emphasizes the need to raise awareness about losses in order to foster public policies and efficient management to mitigate them, given the created economic, environmental and social externalities.

Forced convective drying using a wind turbine mechanically connected to a ventilation fan was hypothesized for low cost and rapid grain drying in developing countries. The idea was tested using an expandable wind turbine blade system with variable pitch, at low wind speeds in a wind tunnel. The design was based on empirical and theoretical models embedded in a graphical user interface (GUI) created to estimate airflow-power requirements for drying ear corn. Output airflow (0.0016 - 0.0052 m3kg-1s-1) increased within the study wind speed range (2.0 - 5.5 m/s). System efficiency peak (8.6%) was observed at 3.5 m/s wind speed. Flow resistance was overcome up to 1m fill depth in 0.5 m x 0.5 m wide drying bin. Drying study at different airflow rates (no forced convection, 0.002 m3kg-1s-1 and 0.008 m3kg-1s-1) were conducted in a controlled environment at 35oC and 45% relative humidity with mean drying time; 40.3, 37.9 and 22.9 h respectively, that reduced with increasing airflow while drying the ear corn from 22% to 15% moisture content. The overall result supports the hypothesis that the wind convection system increased grain drying rates and should be further developed.

Submitted by Carla Segatto Strini Paixão (ca_paixao@live.com) on 2018-06-14T16:31:26Z No. of bitstreams: 1 Tese_Carla.pdf: 1311888 bytes, checksum: 5200851f1f76ad510e670ba7f602977e (MD5) / Rejected by Neli Silvia Pereira null (nelisps@fcav.unesp.br), reason: Solicitamos que realize correção na submissão seguindo as orientações abaixo: 1 - Está faltando o certificado de aprovação no arquivo em pdf. 2 - Encaminhar novamente o arquivo todo, com o certificado de aprovação, em pdf. Agradecemos a compreensão. on 2018-06-15T17:24:28Z (GMT) / Submitted by Carla Segatto Strini Paixão (ca_paixao@live.com) on 2018-06-25T00:54:36Z No. of bitstreams: 1 Tese_Carla-2.pdf: 1920361 bytes, checksum: 1a15616e02ddd976f02a2606d549e8f8 (MD5) / Approved for entry into archive by Neli Silvia Pereira null (nelisps@fcav.unesp.br) on 2018-06-25T18:46:11Z (GMT) No. of bitstreams: 1 paixao_css_dr_jabo.pdf: 1920361 bytes, checksum: 1a15616e02ddd976f02a2606d549e8f8 (MD5) / Made available in DSpace on 2018-06-25T18:46:11Z (GMT). No. of bitstreams: 1 paixao_css_dr_jabo.pdf: 1920361 bytes, checksum: 1a15616e02ddd976f02a2606d549e8f8 (MD5) Previous issue date: 2017-12-19 / A colheita mecanizada de soja é uma operação fundamental para a finalização de seu ciclo produtivo, porém a ausência de metodologias eficientes para quantificação das perdas, não tem contribuído para melhoria continua deste processo agrícola. Associado a isto, ainda existem inúmeros fatores que podem influenciar a qualidade da operação da colheita de soja, sendo difíceis de serem analisados e interpretados, pois as relações entre as variáveis são complexas. Para tentar suavizar essa complexidade, abordagens multivariadas, como Análise de Componentes Principais (ACP) e Análise Fatorial (AF), podem ser uma alternativa para extrair informações da base de dados gerados durante a colheita. E por fim, para monitorar a operação com base no nível de qualidade que a mesma está sendo realizada, o controle estatístico de processo, com uso de gráficos multivariados torna-se essencial, para as variáveis que possuem correlação. Diante disto, objetivou-se neste trabalho determinar as variáveis que mais afetam a qualidade operacional da colheita mecanizada de soja, por meio de análises uni e multivariada. O trabalho foi realizado em março de 2016, em área agrícola no município de Ribeirão Preto-SP, sendo utilizada uma colhedora da marca John Deere, modelo 1470, com sistema de trilha do tipo tangencial e separação por saca-palhas. O processo foi considerado incapaz de manter as perdas da colheita mecanizada de soja em níveis aceitáveis durante toda a operação para as duas armações. A análise fatorial permitiu a seleção de quatro indicadores da colheita mecanizada de soja, explicando 76,4% da variância total. As cartas de controle multivariadas foram mais eficazes para determinar a não aleatoriedade no monitoramento de processo com variáveis correlacionadas. / The mechanical harvesting of soybeans is a fundamental operation to the end of its productive cycle, but the absence of efficient methodologies to quantify losses has not contributed to the continuous improvement of this agricultural process. Associated with this, there are still many factors that can influence the quality of the soybean harvesting operation, being difficult to analyze and interpret because the relationships among the variables are complex. To attempt to soften this complexity, multivariate approaches such as Principal Component Analysis and Factorial Analysis may be an alternative to extract information from the database generated during harvesting. Finally, to monitor the operation based on the level of quality that is being performed, the statistical process control, using multivariate graphs becomes essential, for the variables that have correlation. Therefore, the aimed of this study was to determine the variables that most affect the operational quality of the soybean mechanized harvest, through uni and multivariate analyzes. The work was carried out in March 2016, in an agricultural area in the city of Ribeirão Preto-SP, using a John Deere brand model 1470 harvester with a tangential type track system and straw picking. The process was found to be unable to keep soybean harvest losses at acceptable levels throughout the operation for the two frames. The factorial analysis allowed the selection of four indicators of the soybean mechanized harvest, explaining 76.4% of the total variance. Multivariate control charts were more effective in determining non-randomness in process monitoring with correlated variables.