Selection and propagation of two species of the genus Hymenaea

O objetivo deste trabalho foi avaliar os padr?es de varia??o fenot?picos de duas esp?cies do g?nero Hymenaea com rela??o ?s caracter?sticas biom?tricas dos frutos e sementes, germina??o e produ??o de mudas. Al?m disso, objetiva ainda analisar o comportamento germinativo de sementes submetidas ? temperatura subzero e propor a aplica??o uma metodologia que permita avaliar tal comportamento ao longo do tempo. Os frutos utilizados foram coletados em matrizes de Jatob? procedentes de Curvelo-MG e Diamantina-MG. Os experimentos foram conduzidos no Centro Integrado de Propaga??o de Esp?cies Florestais ? CIPEF/UFVJM em Diamantina, cujos trabalhos foram divididos em tr?s cap?tulos. No primeiro, foram coletados frutos de cinco matrizes de Hymenaea courbaril e de sete matrizes de Hymenaea matiana. Foram avaliados quarenta e nove frutos por matriz quanto as seguintes vari?veis: peso dos frutos e sementes/fruto, comprimento, largura e espessura. A partir desses frutos, foram avaliadas, aleatoriamente, cem sementes por matriz quanto ao comprimento, ? largura e ? espessura. Foi realizado tamb?m o teste de germina??o por matriz e o crescimento de mudas dessas esp?cies foi avaliado. Houve diferen?as significativas para todas as vari?veis analisadas entre esp?cies e matrizes, demonstrando assim a possibilidade de selecionar matrizes espec?ficas de acordo com um determinado interesse. No segundo cap?tulo, sementes de Hymenaea courbaril foram submetidas ao armazenamento em freezer, (-20?C), sob cinco tempos de congelamento (tratamentos): zero, tr?s, seis, nove e doze dias. Avaliaram-se o IVG, a germina??o (%) e o crescimento inicial das mudas. Os efeitos dos tratamentos sobre as vari?veis IVG e percentagem de germina??o n?o foram significativos. O teste de identidade de modelos n?o lineares foi eficaz na discrimina??o dos efeitos dos tratamentos e evidenciou ainda n?o haver diferen?as entre as curvas ajustadas de germina??o acumulada para os tempos de congelamento de seis, nove e doze dias. Foi poss?vel constatar a superioridade do tratamento de tr?s dias de congelamento para as vari?veis germina??o e emerg?ncia. Quanto ao crescimento das mudas, este n?o foi afetado pelos tratamentos aplicados. O ?ltimo cap?tulo consistiu no uso do teste de identidade de modelos n?o lineares para avaliar a germina??o acumulada e compar?-lo com ?ndices de valores ?nicos. Essa metodologia foi eficaz em discriminar os comportamentos germinativos das curvas geradas pelas diferentes equa??es, ao contr?rio dos ?ndices de valores ?nicos que foram estatisticamente iguais.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)Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Ci?ncia Florestal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2012.ABSTRACT The objective of this study was to evaluate the patterns of phenotypic variation in two species of the genus Hymenaea, in relation to biometric characteristics of fruits and seeds, germination and seedling production. And also at analyzing the germination of seeds submitted to subzero temperatures and suggest to apply a methodology to assess such behavior over time. The fruits used in this study were collected from matrices of jatoba proceeding from Curvelo-MG and Diamantina-MG. The experiments were conducted in the Integrated Center for Forest Research and Studies ICFRS/UFVJM in Diamantina-MG. Whose works were divided into three chapters. In the first fruits were collected from five matrices of Hymenaea courbaril and seven matrices of Hymenaea matiana. Were evaluated forty nine fruits by matrices and the following variables: weight of the fruits and seeds, length, width and thickness. These fruits were evaluated randomly one hundred seeds by matrix as length, width and thickness. Was also held by the seed germination test matrix by matrix and evaluated the growth of seedlings of these species. There were significant differences for all variables between species and matrices. Demonstrating, the possibility to select specific matrices under a particular interest. In the second chapter, seeds of Hymenaea courbaril were submitted to storage in a freezer (- 20 ? C), in five freezing time (treatments): zero, three, six, nine and twelve days. We evaluated the IVG, germination (% G) and early growth of seedlings. The effects of the treatments on the variables IVG and percentage of germination were not significant. The tests of the identity of nonlinear models was effective in the discrimination of treatment effects. Evidenced also no differences between the adjusted curves of accumulated germination for freezing time six, nine and twelve days. It was possible to confirm the superiority of treatment three days of freezing for germination and emergence. Concerning growth of seedlings, this was not affected by treatments. The last chapter, consisted of the use of the tests of the identity of nonlinear models to evaluate the cumulative germination and compare it with indices of single values. This methodology was effective at discriminating the behavior germination of the curves generated by the different equations, unlike the indices than single values which were statistically equal