Orientador: Priscila Lupino Gratão / Resumo: A seca é um problema substancial que afeta negativamente parte das áreas de cultivo de cana-de-açúcar, o que limita a produção das lavouras. O déficit hídrico provoca uma redução no crescimento e desenvolvimento das plantas devido à superprodução descontrolada de espécies reativas de oxigênio (ERO). Por outro lado, a aplicação de herbicidas para controle de plantas daninhas é uma estratégia muito usual de manejo nas culturas para manter altos índices de produtividade, mesmo quando as culturas são afetadas por condições adversas, como a seca. Assim, o objetivo deste trabalho foi investigar as diferentes respostas bioquímicas e no crescimento de duas cultivares de cana-de-açúcar, um tolerante à seca (CTC 9002) e outra tolerante a herbicidas (CTC 2), que caracterizem maior tolerância a condição de déficit hídrico associada à aplicação de herbicidas com diferentes mecanismos de ação. Os tratamentos foram dispostos em esquema fatorial triplo 2 x 2 x 3, sendo o fator cultivares CTC2 e CTC9002, fator condição hídrica de 70% ou 35% da capacidade de campo e fator herbicida, ametrina (1750 g i.a. ha-1), sulfentrazone (700 g i.a. ha-1) ou sem aplicação. A peroxidação lipídica, as concentrações de H2O2 e prolina; as atividades antioxidantes das enzimas superóxido dismutase (SOD, EC 1.15.1.1), catalase (CAT, EC 1.11.1.6), ascorbato peroxidase (APX, EC 1.11.1.11), glutationa redutase (GR, EC 1.6.4.2); e o acúmulo de massa seca da parte aérea e da raiz foram analisados. A aplicação do herbi... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Drought is currently a substantial problem worldwide, affecting part of sugarcane grown areas, and it is the main yield-limiting factor of crops. Drought stress provokes a reduction in growth and development due to uncontrolled overproduction of reactive oxygen species (ROS). By the other way, herbicide application to control weeds is a common crop management strategy to maintain high sugarcane yields, even when crops are affected by adverse conditions, such as drought. Thus, the aim of this study was to investigate differences in biochemical and growth responses of two sugarcane genotypes, drought-and herbicide-tolerant, which characterize a greater tolerance to drought stress condition combined to herbicides application with different modes of action. The treatments were arranged in a 2 x 2 x 3 triple factorial scheme, with the cultivar factor CTC2 and CTC9002, a water condition factor of 70% or 35% of field capacity and herbicide factor, ametryn (1750 g a.i ha-1 ), sulfentrazone (700 g a.i ha -1 ) or without application. Lipid peroxidation, H2O2 and proline content; the activities of superoxide dismutase (SOD, EC 1.15.1.1), catalase (CAT, EC 1.11.1.6), ascorbate peroxidase (APX, EC 1.11.1.11), glutathione reductase (GR, EC 1.6.4.2); and shoot and root dry mass accumulation were analyzed. The ametryn herbicide application was harmful to sugarcane plants due to the higher lipid peroxidation and root dry mass reduction. Increased GR activity in response to sulfentrazone appli... (Complete abstract click electronic access below) / Doutor

Orientador: Antonio de Goes / Resumo: A ferrugem alaranjada da cana-de-açúcar (FA), causada por Puccinia kuehnii, é responsável por superior a 40% na produtividade de genótipos de cana-de-açúcar suscetíveis e intermediários. Nesse estudo foram realizados três experimentos. No experimento E1 foi avaliado o efeito do número de aplicações de fungicida piraclostrobina + epoxiconazole (PE) no município de Olímpia-SP, em E2 foi avaliado o efeito do número de aplicações de fungicida piraclostrobina + epoxiconazole (PE) no município de Catigua-SP, ambos em épocas distintas, e em E3 foi avaliado o efeito do volume de calda de PE no controle da doença. A partir dos dados obtidos nos experimentos E1 e E2, foi também avaliada a viabilidade econômica do controle da FA da cana-de-açúcar. Os experimentos foram realizados em dois locais, Olímpia e Catiguá, Estado de São Paulo, sendo empregada a cultivar SP81-3250, em quarto ciclo, após o terceiro corte, em estádio de desenvolvimento (Elongação do colmo; Crescimento intenso; Início do acúmulo de sacarose) da cultura. Em E1 e E2 usou-se o delineamento experimental em blocos ao acaso (DBC), com quatro tratamentos, sendo 0 (testemunha), 1, 2 e 3 aplicações. Cada parcela foi constituída por quatro linhas de 8 metros, espaçadas de 1,5 metros. Foram realizadas sete avaliações, com as quais determinou-se a severidade, a partir das quais foi obtida a área abaixo da curva de progresso da doença (AACPD). Também foi estimado o rendimento de colmos, expresso em tonelada de colmos por hectare... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The orange rust of sugarcane (FA), caused by Puccinia kuehnii, is responsible for over 40% in the yield of susceptible and intermediate sugarcane genotypes. Three experiments were performed in this study. In the E1 experiment, the effect of the number of applications of fungicide pyraclostrobin + epoxiconazole (PE) in the municipality of Olímpia-SP, in E2, was evaluated the effect of the number of applications of fungicide pyraclostrobin + epoxiconazole (PE) in the municipality of Catigua-SP, both at different times, and in E3 the effect of the volume of PE syrup on disease control was evaluated. From the data obtained in experiments E1 and E2, the economic viability of sugarcane FA control was also evaluated. The experiments were carried out at two locations, Olímpia and Catiguá, State of São Paulo, and the cultivar SP81-3250 was used, in the fourth cycle, after the third cut, at the development stage (Elongation of the stem, intense growth; sucrose) of the culture. In E1 and E2, the experimental design in randomized blocks (DBC) was used, with four treatments, being 0 (control), 1, 2 and 3 applications. Each plot was constituted by four lines of 8 meters, spaced of 1.5 meters. Seven evaluations were performed, with which the severity was determined, from which the area under the disease progress curve (AACPD) was obtained. The yield of stalks, expressed in ton of stems per hectare (TCH), was also estimated. In E3 a similar procedure was adopted, whose treatments were repres... (Complete abstract click electronic access below) / Mestre

Sugarcane holds great potential as a biofactory for the tailored production of novel products of commercial value. In many cases however, the accumulation of an alien product within the cytoplasm interferes with essential cell metabolism. To avoid potential interference, targeting the accumulation of biofactory products into vacuoles may be beneficial. Vacuoles represent one endpoint of the plant endomembrane system where proteins destined for inclusion must contain appropriate targeting peptide signals. However, targeting peptide signals used previously to direct heterologous proteins to the vacuole have not yet been shown to function efficiently in sugarcane. The emphasis of the work described in this thesis was first to characterise the diversity of vacuole types in selected sugarcane tissues, and second to identify and test the function of putative vacuolar targeting signals identified in vacuolar proteins of sugarcane. In order to investigate vacuole diversity in sugarcane cells, a series of membrane-permeable fluorescent probes were used to assess both the acidity and proteolytic properties of vacuolar compartments. It is clear that even from early in development, large vacuoles filled most of the volume of storage parenchyma cells within the developing sugarcane stem. These vacuoles were intensely acidic and contained active aminopeptidases. In leaf cells, vacuoles labelled by chromogenic indicators and enzyme substrates appear much more diverse in pH and proteolytic intensity owing to the multiple functions that leaf cells participate in. As the predominant sugarcane vacuole in vegetative tissues appears to be proteolytic, sugarcane sequences showing homology to proteases and protease inhibitors in other plant species were aligned and compared to identify potential vacuolar targeting signals. This analysis revealed the presence of several candidate vacuolar targeting motifs which displayed high conservation across plant homologues. One such motif, represented by the sequence IRLPS, was identified in the N-terminal region of a legumain protein from sugarcane, which was homologous to known vacuolar processing enzymes in other species. To test the efficacy of the legumain targeting signal and to compare with other motifs, a series of GFP reporter constructs was synthesised and expressed in sugarcane. The sugarcane legumain vacuole targeting signal was particularly efficient at directing an otherwise secreted GFP fusion protein into a large acidic and proteolytic vacuole in sugarcane callus cells as well as in diverse plant species. In mature sugarcane transgenic plants, the stability of GFP fusion proteins in the vacuole appeared to be dependent on cell type, suggesting that the vacuolar environment can vary in its ability to degrade introduced proteins. The legumain vacuole targeting signal was further tested for its ability to direct an avidin protein and a fructosyltransferase enzyme into the lytic vacuole of transgenic sugarcane plants. Avidin, derived initially from chicken egg white, is a glycoprotein that displays a high affinity to the vitamin biotin. For this reason it has been investigated for use in sugarcane as a biocontrol agent against cane grub species. For the production of avidin in planta careful targeting to an appropriate subcellular location is required to avoid a detrimental depletion of available plant cell biotin reserves. When the legumain targeting signal was fused to avidin and expressed as a stably integrated transgene, the avidin protein was detected by immunoblotting but appeared to be proteolytically cleaved within the lytic vacuole in all sugarcane tissues analysed. These plants were phenotypically indistinguishable from controls, indicating that avidin did not appreciably deplete cellular biotin reserves while in transit through the endomembrane system. In contrast, when avidin was designed for either retention in the endoplasmic reticulum or for transit to a different type of vacuole using a heterologous targeting signal, stably transformed plants exhibited a biotin deficient phenotype. This suggests that the legumain vacuole targeting signal was efficient at directing heterologous proteins to a lytic type vacuole where they can be degraded and inactivated if susceptible to proteolysis. When the fructosyltransferase (ftf) gene from Streptococcus salivarius was stably transformed into sugarcane and directed into the lytic vacuole using the legumain vacuole targeting signal, no fructan product could be detected. The low pH and proteolytic environment of this vacuole together with low expression of this bacterial transgene most likely resulted in minimal Ftf activity. Taken together, evidence is presented that the legumain vacuolar targeting signal functions efficiently in directing transgene products such as GFP, avidin and a fructosyltransferase enzyme into a lytic type vacuole. This vacuole has been demonstrated to be both acidic and proteolytic and therefore strategies to improve the stability of heterologous proteins targeted to this vacuolar environment are required and may be specific to the product in question.

Orientador: Salatiér Buzetti / Banca: Antonio Cesar Bolonhezi / Banca: Marcelo Andreotti / Banca: Takashi Muraoka / Banca: Cassio Hamilton Abreu Junior / Resumo: A adubação representa cerca de 20% dos custos de produção da cana-de-açúcar e entre os nutrientes utilizados, o potássio constitui o elemento mais exigido pela cultura, juntamente com o nitrogênio. O trabalho teve como objetivo estudar os efeitos de doses de nitrogênio e de potássio na produtividade e qualidade das socas de cana-de-açúcar no 3º e 4º ciclos e no 4º ciclo em áreas com palhada (CCP) e sem palhada (CSP) sobre o solo. Os experimentos com os 3º e 4º ciclos foram conduzidos nos anos de 2006 a 2008 com a variedade RB 83-5486 na fazenda Vale da Pecuária, município de Selvíria-MS, e os experimentos com 4º ciclo da cana- de-açúcar em áreas com e sem palhada sobre o solo foram conduzidos nos anos de 2007 a 2008 com variedade RB 86-7515 nas fazendas A Raimundo e Retiro II, respectivamente, no município de Aparecida do Taboado-MS. Todos os experimentos foram desenvolvidos em áreas administradas pela Usina Alcoolvale S/A com quatro doses de nitrogênio (40, 80, 120 e 160 kg ha-1 de N), na forma de uréia, e quatro doses de potássio (40, 80, 120 e 160 kg ha-1 de K2O), na forma de cloreto de potássio, em um esquema fatorial 4x4, totalizando 16 tratamentos dispostos em blocos ao acaso, com quatro repetições. Foram avaliados os teores foliares de macronutrientes nas folhas e nos colmos, açúcares redutores do caldo e da cana, pol do caldo e da cana, pureza do caldo, brix, fibra, produtividade agroindustrial, produção de matéria-seca e produtividade de colmos. Para os experimentos 3º e 4º ciclos da cana-de- açúcar com a variedade RB 83-5486 as doses de N e de K aumentaram os teores de macronutrientes na folha e no colmo. Para os indicadores de qualidade da cana-de-açúcar, houve apenas efeito das doses de N no teor de brix no 3º ciclo, evidenciando que a matéria- prima estava com boa qualidade tecnológica e dentro... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The fertilization represents around 20% of the production cost of sugar-cane crop and potassium constitutes its most demanded nutrient, together with nitrogen. The study had the objective of evaluating the effects of nitrogen and potassium rates on 3th and subsequent 4th cycle of sugar-cane crop (ratoon), and on 4th cycle of this crop in areas with or without cane trash burning, on its productivity and quality. The experiments of 3th and 4th cycles were conducted from 2006 to 2008 with the RB 83-5486 variety at Vale da Pecuária farm, Selvíria- MS, and the experiments with 4th cycle of the sugar-cane in areas managed with (+TB) or without (-TB) cane trash burning were conducted from 2007 to 2008 with variety RB 86-7515 at A Raimundo and Retiro II, respectively, in Aparecida do Taboado-MS. All experiments were carried out in areas administered by Usina Alcoolvale S/A, in a randomized block design using a 4x4 factorial scheme, with four rates of nitrogen (40, 80, 120 and 160 kg ha-1), as urea and four of potassium (40, 80, 120 and 160 kg ha-1 of K2O), as potassium chloride, totalizing 16 treatments with four replicates. The macro and micronutrients content in leaf and stem, reducing sugars, pol, purity, Brix, fiber content, tillering number in 10 meters, agro industrial productivity, dry matter and cane productivity were evaluated. For the experiments of 3th and 4th cycles N and K rates increased the leaf and stem macro and micronutrients contents. For the quality indicators, there was effect of N rates only on Brix in the 3th cycle, observing that the raw material had good technological quality and within the adequate patterns. The K rates increased the agro industrial productivity, dry matter and cane productivity only for the 4th cycle. The cane yield increased linearly with K rates. For the experiments of 4th cycle with RB 86-7515, the N and K rates increased... (Complete abstract click electronic access below) / Doutor

Orientador: Dilermando Perecin / Resumo: O melhoramento genético tem contribuído com o setor sucroalcooleiro lançando cultivares mais produtivas, resistentes ou tolerantes às principais pragas e doenças da cultura, fazendo com que o Brasil consiga suprir sua demanda por açúcar e etanol. Poucos são os estudos acerca da importância relativa dos parentais na performance das progênies para os atributos de interesse econômico em cana- de-açúcar. Os objetivos deste trabalho foram verificar a influência de efeito recíproco para caracteres de importância agronômica em cana-de-açúcar quanto ao número de colmos (lnNC), brix e tonelada de biomassa por hectare (TBIOH) e avaliar 8 famílias de cana-de-açúcar pelo método de modelos mistos, destacando as famílias e progênies superiores para os atributos analisados. Quatro cruzamentos biparentais e seus recíprocos, gerando 8 famílias de irmãos completos e a testemunha IACSP95-5000, foram avaliados em delineamento de blocos casualizados, com 20 blocos. As predições das famílias mostraram variabilidade para número de colmos (lnNC), brix e biomassa de touceira (BIO), o que permite seleção. Verificou-se a existência de efeitos maternos, paternos e interação entre eles para as características de brix e TBIOH. O parental feminino apresentou maior contribuição na determinação da performance do brix das progênies, porém, nem sempre o parental com alto teor de brix irá produzir progênie com performance superior. Entre os genótipos estudados, foi recomendada a utilização do parental feminino ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Sugarcane breeding has contributed to the sector, releasing varieties more productive, resistant or tolerant to major diseases and pests of the crop. The purpose of this study was to verify the influence of reciprocal effect to sugarcane agronomic traits: stalk number, brix and tonnes of biomass per hectare (TBIOH) and to evaluate eight sugarcane families by mixed model highlighting the superior families and progenies for the traits analyzed. Progenies from four biparental crosses and their reciprocal crosses were assessed in plant cane and first ratoon cane cycles. The experiment design used was completely randomized blocks, with 20 replications and 9 treatments (8 sugarcane families and a cultivated variety IACSP95-5000). Maternal, paternal and maternal x paternal interaction for the traits brix and TBIOH were observed. Significant reciprocal differences (P≤0.05) were found for stalk number brix and TBIOH in both cane cycles. Half of the assessed reciprocal crosses showed favorable effects within the reciprocals (P≤0,10) with a brix increase in the progeny means ranging from 0.9 to 1.7, using female parent IACSP98-2053. TBIOH showed significant effect within every reciprocal cross assessed in plant cane cycle. The predictions showed variability for stalk number, brix and biomass. The female parent IACSP01-2419 and the male parent IACSP95- 5000 can be indicated as female parents to obtain individual progeny with higher brix content and TBIOH productivity. The commercial vari... (Complete abstract click electronic access below) / Doutor

Orientador: José Eduardo Pitelli Turco / Banca: Antonio Carlos Barreto / Banca: Anaira Denise Caramelo / Banca: José Renato Zanini / Banca: David Luciano Rosalen / Resumo: O Brasil é lider mundial na produção de açúcar e etanol, devido ao intenso cultivo da cultura de cana-de-açúcar principalmente na região Sudeste do país. No entanto sua expansão em outras áreas vem ganhando força nos últimos anos, o que tem acarretado variações significativas nas safras devido aos problemas relacionados ao clima da região e caracterísiticas topográficas do terreno. A limitação hídrica e as altas temperaturas do ar podem gerar danos irrerversíveis às plantas e impactos ao produtor final. O uso de índices de estresse hídrico nas fases de desenvolvimento da cultura pode atuar como uma ferramenta essencial no manejo da irrigação, prevenindo os efeitos negativos desencadeados pelo estresse hídrico nas plantas. Objetivou-se com este trabalho determinar índices de estresse hídrico em cana-de-açúcar nas diferentes fases de desenvolvimento. Para isso avaliaram-se os índices de estresse hídrico nas diferentes fases de desenvolvimento das plantas, o potencial de água no solo, o potencial matricial de água, a taxa fotossintética e o índice do conteudo de clorofila das folhas e a condução do sistema produtivo no período de coleta de dados. A pesquisa foi desenvolvida na área experimental do Departamento de Engenharia Rural da FCAV/UNESP, denominada "Bacia Hidrográfica Experimental", utilizando superfícies caracterizadas como H1 (superfície horizontal na capacidade de campo) e H2 (superfície horizontal, sob déficit hídrico induzido), 20N e 40N (superfícies com 20 e 40% de ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Brazil is the world leader in the production of sugar and ethanol, due to the intense cultivation of sugarcane cultivation mainly in the Southeast region of the country. However, its expansion in other areas has been gaining strength in the last years, which has caused significant variations in the harvests due to problems related to the climate of the region and topographic characteristics of the terrain. Water limitation and high air temperatures can generate irreversible damage to the plants and impacts the final producer. The use of water stress indices in the development stages of the crop can act as an essential tool in the management of irrigation, preventing the negative effects triggered by water stress in the plants. The objective of this work was to determine water stress indexes in sugarcane at different stages of development. For this, the water stress indexes were evaluated in the different phases of plant development, soil water potential, water matrix potential, photosynthetic rate and index of leaf chlorophyll content and the conduction of the productive system in the soil. period of data collection. The research was developed in the experimental area of the Department of Rural Engineering of the FCAV / UNESP, denominated "Experimental Hydrographic Basin", using surfaces characterized as H1 (horizontal surface in the field capacity) and H2 (horizontal surface, under induced water deficit), 20N and 40 N (surfaces with 20 and 40% slope and northern exposure, under induced water deficit), 20S and 40S (surfaces with 20 and 40% slope and south exposure, under induced water deficit), 20E and 40E (surfaces with 20 and 40% slope and east exposure, under induced water deficit) and 20 and 40W (areas with 20 and 40% slope and west exposure... (Complete abstract click electronic access below) / Doutor

Submitted by Aycon Tinoco Lisboa Frazao (aycon.lisboa@ifma.edu.br) on 2018-08-06T18:39:46Z No. of bitstreams: 1 diss_agro_08.pdf: 1718321 bytes, checksum: afe36fe0775b84febaec98b23b163858 (MD5) / Approved for entry into archive by Neli Silvia Pereira null (nelisps@fcav.unesp.br) on 2018-08-07T12:54:34Z (GMT) No. of bitstreams: 1 frazao_atl_me_jabo.pdf: 1718321 bytes, checksum: afe36fe0775b84febaec98b23b163858 (MD5) / Made available in DSpace on 2018-08-07T12:54:34Z (GMT). No. of bitstreams: 1 frazao_atl_me_jabo.pdf: 1718321 bytes, checksum: afe36fe0775b84febaec98b23b163858 (MD5) Previous issue date: 2018-07-23 / RESUMO: A PRESENÇA DE PALHA NA MUDA AFETA A QUALIDADE DOS SISTEMAS DE PLANTIO DE CANA-DE-AÇÚCAR? RESUMO - O processo de colheita mecanizada de mudas de cana-de-açúcar é decisivo na operação seguinte, a de plantio mecanizado da cultura, principalmente nos meses de outubro/novembro, nos quais há maior estresse hídrico e temperatura elevadas. Assim, a quantidade de palha retida no rebolo durante o processo de colheita mecanizada, pode reduzir a quantidade de gemas inviáveis por danos mecânicos e proteger as gemas das condições climáticas adversas. Objetivou-se, avaliar a qualidade de operação de plantio de cana-de-açúcar utilizando mudas com e sem palhada, com utilização de plantadoras e distribuidoras de cana-de-açúcar picada comparados ao plantio semi-mecanizado. O experimento foi conduzido na Fazenda Santa Clara, localizada no município de Pradópolis - SP, com cinco tratamentos sendo, plantadora mecanizada sem palha na muda, plantadora mecanizada com palha na muda, distribuidora mecanizada sem palha na muda, distribuidora mecanizada com palha na muda e plantio semi-mecanizado. A coleta de dados foi realizada em 50 pontos amostrais para cada tratamento, de acordo com as premissas do Controle Estatístico de Processo. A quantidade de gemas inviáveis e as falhas no estande reduziram com a presença de palha no rebolo. A presença de palha no rebolo possibilita o aumento do potencial da área plantada. Dessa forma, a presença de palha na muda melhorou a qualidade do plantio de cana de açúcar. PALAVRAS-CHAVE: cartas de controle, distribuidora, plantadora, Saccharum officinarum / ABSTRACT: THE PRESENCE OF STRAW TRASH ON SEEDLINGS AFFECTS THE QUALITY OF SUGARCANE CROP SYSTEMS? ABSTRACT - The process of sugarcane seedlings mechanized harvesting is decisive in the next operation, which is the mechanized crop planting, mainly in the months of October/November, when the plants experience higher water stress and elevated temperatures. Thus, the amount of straw retained in the stalk during the mechanized harvesting process can reduce the number of non-viable buds due to mechanical damage and protect the buds from adverse climatic conditions. The objective of this study was to evaluate the quality of the sugarcane planting operation using seedlings with and without straw, employing planters and distributors of chopped sugarcane compared to semi-mechanized planting. The experiment was carried out at Santa Clara Farm, located in the city of Pradópolis, SP, Brazil, with five treatments, being: mechanized planter without straw in the seedling, mechanized planter with straw in the seedling, mechanized distributor without straw in the seedling, mechanized distributor with straw in the seedling and semi-mechanized planting. The data collection was performed in 50 sample points for each treatment, according to the premises of the Statistical Process Control. The amount of unviable gems and faults in the stand reduced with the presence of straw on the stalk. The presence of straw in the stalk makes it possible to increase the potential of the planted area. Thus, the presence of straw in the seedling improved the quality of sugarcane cropping. KEYWORDS: control letters, distributor, planter, Saccharum officinarum / Minter: 834320

Submitted by Aycon Tinoco Lisboa Frazao (aycon.lisboa@ifma.edu.br) on 2018-08-16T14:11:15Z No. of bitstreams: 1 Dissertaçao Aycon Final definitiva.pdf: 2201663 bytes, checksum: b6724c23672b5427d5ff9d96216e92ab (MD5) / Approved for entry into archive by Neli Silvia Pereira null (nelisps@fcav.unesp.br) on 2018-08-17T17:11:27Z (GMT) No. of bitstreams: 1 frazao_atl_me_jabo.pdf: 2201663 bytes, checksum: b6724c23672b5427d5ff9d96216e92ab (MD5) / Made available in DSpace on 2018-08-17T17:11:27Z (GMT). No. of bitstreams: 1 frazao_atl_me_jabo.pdf: 2201663 bytes, checksum: b6724c23672b5427d5ff9d96216e92ab (MD5) Previous issue date: 2018-07-23 / Outra / O processo de colheita mecanizada de mudas de cana-de-açúcar é decisivo na operação seguinte, a de plantio mecanizado da cultura, principalmente nos meses de outubro/novembro, nos quais há maior estresse hídrico e temperatura elevadas. Assim, a quantidade de palha retida no rebolo durante o processo de colheita mecanizada, pode reduzir a quantidade de gemas inviáveis por danos mecânicos e proteger as gemas das condições climáticas adversas. Objetivou-se, avaliar a qualidade de operação de plantio de cana-de-açúcar utilizando mudas com e sem palhada, com utilização de plantadoras e distribuidoras de cana-de-açúcar picada comparados ao plantio semi-mecanizado. O experimento foi conduzido na Fazenda Santa Clara, localizada no município de Pradópolis - SP, com cinco tratamentos sendo, plantadora mecanizada sem palha na muda, plantadora mecanizada com palha na muda, distribuidora mecanizada sem palha na muda, distribuidora mecanizada com palha na muda e plantio semi-mecanizado. A coleta de dados foi realizada em 50 pontos amostrais para cada tratamento, de acordo com as premissas do Controle Estatístico de Processo. A quantidade de gemas inviáveis e as falhas no estande reduziram com a presença de palha no rebolo. A presença de palha no rebolo possibilita o aumento do potencial da área plantada. Dessa forma, a presença de palha na muda melhorou a qualidade do plantio de cana de açúcar. / The process of sugarcane seedlings mechanized harvesting is decisive in the next operation, which is the mechanized crop planting, mainly in the months of October/November, when the plants experience higher water stress and elevated temperatures. Thus, the amount of straw retained in the stalk during the mechanized harvesting process can reduce the number of non-viable buds due to mechanical damage and protect the buds from adverse climatic conditions. The objective of this study was to evaluate the quality of the sugarcane planting operation using seedlings with and without straw, employing planters and distributors of chopped sugarcane compared to semi-mechanized planting. The experiment was carried out at Santa Clara Farm, located in the city of Pradópolis, SP, Brazil, with five treatments, being: mechanized planter without straw in the seedling, mechanized planter with straw in the seedling, mechanized distributor without straw in the seedling, mechanized distributor with straw in the seedling and semi-mechanized planting. The data collection was performed in 50 sample points for each treatment, according to the premises of the Statistical Process Control. The amount of unviable gems and faults in the stand reduced with the presence of straw on the stalk. The presence of straw in the stalk makes it possible to increase the potential of the planted area. Thus, the presence of straw in the seedling improved the quality of sugarcane cropping. / Minter: 834320