Resumo: O nitrogênio é um nutriente que pode propiciar efeitos benéficos na produtividade, na qualidade química e fisiológica das sementes de feijão. Assim, é de fundamental importância saber qual o momento adequado para sua aplicação e a fonte de N a ser utilizada, além da interação com a prática da inoculação de sementes com Rhizobium spp., em sistema plantio direto. O objetivo do trabalho foi o de estudar o efeito da inoculação de sementes, fontes e modos de aplicação de nitrogênio no desenvolvimento, produtividade, qualidade química e fisiológica de sementes do feijoeiro de inverno no sistema plantio direto em sucessão a milho e Brachiaria. O delineamento experimental foi o de blocos casualizados em esquema fatorial 2x2x8, com quatro repetições. O trabalho foi desenvolvido em Latossolo Vermelho Distrófico argiloso, Selvíria (MS) em dois anos (2006 e 2007) e os tratamentos foram constituídos pela combinação de inoculação de sementes (presença e ausência) com Rhizobium tropici (estirpes SEMIA 4077 + SEMIA 4080), fontes de nitrogênio (uréia - 45% de N e Entec 26® - 26 % de N + 13% de S + inibidor da nitrificação) e modos de aplicação de nitrogênio (testemunha - sem N, 30 dias antes da semeadura - DAS, 15 DAS, semeadura, 15 dias após semeadura no estádio V2 - DASe, 30 DASe no estádio V4, 1/3 Semeadura + 2/3 15 DASe, 1/3 Semeadura + 2/3 30 DASe) na dose de 90 kg ha-1. A uréia é o adubo nitrogenado recomendado para feijoeiro de inverno irrigado, podendo ser aplicado antecipadamente aos 15 DAS ou na semeadura e/ou cobertura. A inoculação propiciou maior teor de carboidratos (açúcares livres e amido) nas sementes, porém, não tem influencia diretamente na qualidade fisiológica e produtividade / Abstract: Nitrogen is a nutrient that may provide beneficial effects on yield, physiological and chemical quality of common bean seeds. So, it is fundamental importance to know what the right time for its application and the source of N to be used in addition to interaction with the practice of seed inoculation with Rhizobium spp. in no tillage system. The objective of the work was to study the effect of seed inoculation, nitrogen sources and split in the growth, yield, physiological and chemical quality of the common bean seeds in the winter in no tillage system over graminea, in a dystrophic clayey Latosol - Haplustox, MS. The work was carried out in two years (2006 and 2007) in a randomized blocks design using a factorial scheme 2x2x8 and 4 repetitions, constituted by seed inoculation with Rhizobium tropici (presence and absence), two sources of nitrogen (urea - 45% nitrogen and Entec 26® - 26 % de N + 13% de S + DMPP molecules aiming to inhibit nitrification) and eight stadia of nitrogen application (control without N application, 30 days before sowing - DBS, 15 DBS, at sowing - S, 15 days after sowing - DBSe, 30 DBSe, 1/3 S + 2/3 15 DBSe, 1/3 S + 2/3 30 DBSe) at 90 kg ha-1. The urea nitrogen is recommended for irrigated winter common bean and can be applied in advance at 15 DBS or at sowing and/at sidedressing. The inoculation provided higher content of carbohydrates (free sugars and starch) in seeds however, does not directly influence the physiological quality and yield / Orientador: Orivaldo Arf / Coorientador: Salatiér Buzetti / Banca: Marco Eustaquio de Sa / Banca: Kuniko Iwamoto Haga / Banca: Leandro Borges Lemos / Banca: Neli Cristina Belmiro dos Santos / Doutor

Made available in DSpace on 2014-07-29T15:16:34Z (GMT). No. of bitstreams: 1 parte I regiane.pdf: 912177 bytes, checksum: 0b47e257840020aec3acb3cb01014dba (MD5) Previous issue date: 2008-05-29 / The β-1.3-glucanases have several functions in the cell as fungal metabolic in hydrolysis of polysaccharides for possible cellular assimilation; morphogenetic function in the hydrolysis or modifications of the cell wall, which includes growth and extension of the wall, altering the structure and composition of the wall and autolysis. In addition to presenting ecological importance, since these enzymes are involved in biological control, through the process of mycoparasitism. The gender Trichoderma comprises a group of filamentous fungi, saprophytic soil, found on decomposing organic matter in the rhizosphere, and some plants. Considering the importance of β-1.3 glucanases proposing in this study to evaluate the production of β-1.3 - glucanases by T. asperellum using different sources of carbon and nitrogen. The enzyme was produced using cell wall of Rizoctonia solani (PCRS), chitin, chitosan, starch, cellulose, sucrose, maltose, lactose, celobiose and glucose. The best production of enzymes was obtained in the middle containing PCRS, with two bands of activity of polyacrylamide gel were found. Furthermore, the effect of varying concentrations of ammonium sulfate (2, 4, 6, 8, 20, 40 and 60 mM) in the production of β-1.3-glucanase was evaluated during the growth of the fungus in PCRS. A great increase in activity of the enzyme was detected in the presence of nitrogen source. We can see that there was a considerable increase in the expression of the enzyme of low molecular weight at this culture conditions. / As b-1,3-glucanases apresentam diversas funções na célula fúngica como metabólica, na hidrólise de polissacarídeos para eventual assimilação celular; função morfogenética, na hidrólise ou modificações da parede das células, que inclui o crescimento e extensão da parede, alterando sua estrutura e sua composição e autólise. Além de apresentar importância ecológica estas enzimas estão envolvidas no controle biológico, através do processo de micoparasitismo. O gênero Trichoderma compreende um grupo de fungos filamentosos saprófitas de solo, encontrados sobre matéria orgânica em decomposição e na rizosfera de algumas plantas. Considerando a importância das b-1,3-glucanases propõe-se neste trabalho a avaliação da produção de b-1,3-glucanases por T. asperellum utilizando diferentes fontes de carbono e nitrogênio. A enzima foi produzida utilizando parede celular de Rizoctonia solani (PCRS), quitina, quitosana, amido, celulose, sacarose, maltose, lactose, celobiose e glicose. A melhor produção de enzimas foi obtida n o meio contendo PCRS, sendo detectadas duas bandas de atividade em gel de poliacrilamida. Além disto, o efeito de concentrações variadas de (NH4) 2SO4 (2, 4, 6, 8, 20, 40 e 60 mM) na produção de b-1,3-glucanases foi avaliado durante o crescimento do fungo em PCRS. Um aumento considerável na atividade da enzima foi detectado na presença desta fonte de nitrogênio. Pode - se observar que houve um aumento considerável na expressão da enzima de menor massa molecular nestas condições de cultivo.

The aim of this thesis was to develop stable-isotope steady-state metabolic flux analysis (MFA) based on ¹³C labeling to quantify intracellular fluxes of central carbon metabolism in plants. The experiments focus on the analysis of a heterotrophic cell suspension culture of Arabidopsis thaliana (L) Heynh. (ecotype Landsberg erecta). The first objective was to develop a robust methodology based on combining high quality steady-state stable labeling data, metabolic modeling and computational analysis. A comprehensive analysis of the factors that influence the outcome of MFA was undertaken and best practice established. This allowed a critical analysis of the subcellular compartmentation of carbohydrate oxidation in the cell culture. The second objective was to apply the methodology to nutritional perturbations of the cell suspension. A comparison of growth on different nitrogen sources revealed that transfer to an ammonium-free medium: (i) increased flux through the oxidative pentose phosphate pathway (oxPPP) by 10% relative to glucose utilisation; (ii) caused a substantial decrease in entry of carbon into the tricarboxylic acid cycle (TCA); and (iii) increased the carbon conversion efficiency from 55% to 69%. Although growth on nitrate alone might be expected to increase the demand for reductant, the cells responded by decreasing the assimilation of inorganic N. Cells were also grown in media containing different levels of inorganic phosphate (Pi). Comparison of the flux maps showed that decreasing Pi availability: (i) decreased flux through the oxPPP; (ii) increased the proportion of substrate fully oxidised by the TCA cycle; and (iii) decreased carbon conversion efficiency. These changes are consistent with redirection of metabolism away from biosynthesis towards cell maintenance as Pi is depleted. Although published genome-wide transcriptomic and metabolomic studies suggest that Pi starvation leads to the restructuring of carbon and nitrogen metabolism, the current analysis suggests that the impact on metabolic organisation is much less extreme.