Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2018-02-28T20:51:46Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) carolina_mata_machado_barbosa_chaves.pdf: 869125 bytes, checksum: f3a73edd9fc230fa83bcba82ad63bf37 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2018-03-09T20:12:08Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) carolina_mata_machado_barbosa_chaves.pdf: 869125 bytes, checksum: f3a73edd9fc230fa83bcba82ad63bf37 (MD5) / Made available in DSpace on 2018-03-09T20:12:08Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) carolina_mata_machado_barbosa_chaves.pdf: 869125 bytes, checksum: f3a73edd9fc230fa83bcba82ad63bf37 (MD5) Previous issue date: 2017 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG) / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / O enxofre (S) ? um nutriente essencial para crescimento e metabolismo das plantas, e sua defici?ncia pode limitar a produtividade de muitas culturas. A adapta??o de t?cnicas espec?ficas de an?lise espectral para a determina??o do estresse nutricional causado por este nutriente pode permitir a detec??o precoce da sua defici?ncia e suplementa??o de precis?o na aduba??o corretiva das plantas. Esse experimento foi conduzido com o objetivo de determinar se a reflect?ncia foliar obtida atrav?s do mini espectr?metro pode ser utilizada para detectar a defici?ncia de S em mudas de Eucalyptus urophylla. Durante 90 dias as mudas foram cultivadas em solu??o nutritiva de Clark modificada completa (sem omiss?o de S) e com omiss?o de S. Os sintomas visuais de defici?ncia de S foram observados e fotografados semanalmente. A cada 15 dias foram avaliados altura e di?metro das plantas e leituras nas folhas diagn?sticos, com o mini espectr?metro. Ao final de cada avalia??o, amostras de folhas diagn?sticos foram preparadas e submetidas ?s an?lises qu?micas do material vegetal dos teores de nutrientes, posteriormente as mudas foram separadas em ra?zes, caule e folhas para obten??o da massa seca total e dos seus componentes. Ap?s calcular a primeira derivada das reflect?ncias obtidas nas leituras com o mini espectr?metro, obteve-se a posi??o dos pontos de inflex?o. Foi realizado ainda um estudo de regress?o linear m?ltipla entre os teores de nutrientes das folhas diagn?sticos como vari?veis dependentes, e a produ??o de massa seca da parte a?rea e valores obtidos para o IPP como vari?veis independentes. A defici?ncia de S causou altera??es nas propriedades morfol?gicas e fisiol?gicas das plantas de Eucalyptus, o que refletiu nas mudan?as das propriedades espectrais foliares da esp?cie em quest?o. Os sintomas visuais de defici?ncia de S iniciaram-se aos 28 dias ap?s a aplica??o dos tratamentos (DAT), intensificando-se ao longo do experimento. Foi observado clorose nas folhas novas, caule mais delgado e redu??o no crescimento das mudas quando comparados ao tratamento completo. A an?lise nutricional detectou redu??o nas concentra??es de S foliar e defici?ncia do nutriente nas plantas aos 45 DAT. Contudo, somente aos 75 dias a defici?ncia de S alterou a reflect?ncia das mudas com omiss?o de S, deslocando o ponto de inflex?o para comprimentos de ondas mais curtos (? 700 ?m), ou seja, quando o aparelho (mini espectr?metro) conseguiu detectar defici?ncia nutricional de S nas plantas de Eucalyptus. A defici?ncia de S tamb?m reduziu a altura, di?metro e produ??o de massa seca total e dos seus componentes aos 75 DAT. A posi??o do ponto de inflex?o e a massa seca da parte a?rea apresentaram alta correla??o com a concentra??o de S foliar. As an?lises de regress?o linear m?ltipla e de correla??o simples indicaram que os valores de reflect?ncia foliar estimados pelo mini espectr?metro e pela massa seca da parte a?rea estavam estreitamente correlacionados com as concentra??es de S nas folhas das mudas de Eucalyptus (r2=0,99). Os resultados obtidos sugerem que a reflect?ncia espectral demonstra alto potencial como ferramenta diagn?stico para estimar a concentra??o de S foliar em Eucalyptus por meio do mini espectr?metro. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Produ??o Vegetal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2017. / Sulfur (S) is an essential nutrient for plant growth and metabolism, its deficiency can limit the productivity of many crops. The adaptation of specific remote sensing and spectral analysis techniques for the determination of nutrient stress in plants could allow early detection and precise supplementation for corrective fertilization. This experiment was conducted with the objective of determining if the leaf reflectance obtained through the mini spectrometer can be used to detect S deficiency in Eucalyptus urophylla seedlings. During 90 days the seedlings were grown in complete nutrient solution of Clark (without omission of S) and with omission of S. The visual symptoms of S deficiency were observed and photographed weekly. Every 15 days, plants height and diameter were evaluated, and readings on the diagnostic leaf were taken with the mini spectrometer. At the end of each evaluation the samples of the diagnostic leaves were prepared and submitted to the chemical analyzes of nutrient contents of the plant material, later the seedlings were separated into roots, stem and leaves to obtain the mass of total dry matter and its components. After calculating the first derivative of the reflectances obtained in the readings with the mini-spectrometer, the position of the inflection points was obtained. A multiple linear regression study was carried out between the nutrient contents of the diagnostic leaves as dependent variables and the shoot dry matter yield and values obtained for the position of the inflection points as independent variables. Sulfur deficiency caused changes in the morphological and physiological properties of Eucalyptus plants, which reflected changes in the leaf spectral properties of the species. The visual symptoms of S deficiency began at 28 days after application of the treatments, intensifying throughout the experiment. It was observed chlorosis in the new leaves, slender stem and reduction in the growth of the seedlings when compared to the complete treatment. Nutritional analysis detected a reduction in the foliar S concentrations and nutrient deficiency in plants at 45 days after application of the treatments. However, only at 75 days S deficiency altered the reflectance of the seedlings under S omission, shifting the inflection point to shorter wavelengths (? 700 ?m),that is, when the device (mini spectrometer) was able to detect nutritional deficiency of S in Eucalyptus plants. Sulfur deficiency also reduced the height, diameter and yield of total dry mass and its components at 75 days after application of the treatments. The position of the inflection point and the shoot dry mass presented a high correlation with the concentration of leaf sulfur. Multiple linear regression and simple correlation analyzes indicated that leaf reflectance values estimated by the mini spectrometer and through MSPA were closely correlated with the concentrations of S in the leaves of the Eucalyptus seedlings (r2 = 0.99).The results obtained suggest that the spectral reflectance demonstrates high potential as a diagnostic tool to estimate the leaf sulfur concentration in Eucalyptus using the mini-spectrometer.