In 2014, a new and serious leaf and shoot disease of unknown aetiology appeared in Eucalyptus plantations of North Sumatra, Indonesia. The disease is characterized by black necrotic spots that initially appear on young leaves and petioles, which become scab‐like as the lesions age. Infected trees respond to infection by producing shoots with small leaves that commonly appear feathered. Fruiting structures typical of most foliar pathogens are not seen, but using scanning electron microscopy (SEM), fungal spores are evident and associated with the scab‐like structures. Using culture‐dependent methods, cultures resembling a species of Elsinoe were isolated from the lesions. DNA sequence comparisons for four gene regions, as well as morphological observations, showed that the fungus is an undescribed species in Elsinoe, for which the name Elsinoe necatrix sp. nov. is provided. Pathogenicity trials on a Eucalyptus clone with the Elsinoe species resulted in scab‐like structures similar to those observed under field conditions and the fungus was easily reisolated from the resulting lesions. This study includes a description of the pathogen and characterization of the disease, for which the name Eucalyptus scab and shoot malformation is suggested.
, Nilton César Fiedler 6 e Graziela Baptista Vidaure 7 RESUMO -Sabe-se da existência de influência do local de crescimento nas propriedades da madeira e que estas são influenciadas principalmente pela sua estrutura anatômica. Este trabalho teve como objetivo avaliar parâmetros quantitativos da estrutura anatômica da madeira de eucalipto de um clone de híbrido natural de Eucalyptus grandis W. Hill ex-Maiden, ocorrentes na localidade de Rio Claro-SP, com 64 meses de idade. As 138 árvores foram cultivadas nos os municípios de Aracruz, Domingos Martins, Alto Rio Novo e São Mateus -ES e Mutum e Aimorés -MG. Os parâmetros anatômicos mensurados foram o diâmetro e a frequência vascular, o comprimento, a largura, o diâmetro do lume e a espessura da parede das fibras e ainda a altura, largura e frequência de raios. De acordo com os resultados obtidos pode-se concluir que relativo aos vasos houve diferenças significativas entre as regiões. Quanto aos raios, também foram verificadas diferenças significativas relativas à altura, largura e frequência diversas regiões. As madeiras produzidas na região de Aracruz possuem fibras de comprimento e espessura de paredes muito inferiores às produzidas nas demais regiões estudadas.Palavras-chave: Madeira de eucalipto, Clone e Estrutura anatômica. ANATOMICAL STRUCTURE MEASUREMENTS IN EUCALYPT WOOD THAT GROWN IN DIFFERENTS PLACES
The objective of the present study was to investigate whether the performance of an individual in clonal testing was affected by the location of the initial selection. The study also evaluated the effect of mass selection and BLUP (Best Linear Unbiased Prediction) on the performance of individuals in the progeny test and the clonal test. In the progeny test, 62 half-sib E. grandis families, 68 half-sib E. urophylla families and 62 full-sib families between E. grandis and E. urophylla, plus four checks were evaluated totaling 196 treatments. The experiments were carried out at three sites: Aracruz and São Mateus, in Espírito Santo State and Caravelas, Bahia State, Brazil. The 1000 best individuals were classified by mass selection and BLUP. In the clonal tests 257 clones were evaluated in two locations: Aracruz and Caravelas. In both the progeny test and the clonal test, two years after planting, the circumference at breast height and basic wood density were measured and the sum of standardized variables (Z) was estimated for simultaneous selection of both characteristics. The results indicated that the origin of the individual in a progeny test had a small effect on the performance of the clone when evaluated in other environments; the estimates of realized heritability and the linear regression coefficient were small in all the selection strategies. Thus, the correlation between the performance of trees selected in progeny tests and their respective clones in the clonal test was small.
The objective of this study was to identify eucalyptus clones for the production of sawed timber based on dendrometric variables and longitudinal residual deformation (LRD), analyzing the correlation between these characteristics. 20 Eucalyptus grandis x Eucalyptus urophylla clones with 13 years of age were analyzed. The crown size, diameter at breast height (DBH) and bark thickness were measured. There was a significant difference between the clones for DBH, LRD and bark thickness. There was no significant correlation between DBH and DRL. The correlation was significant between DBH and crown size, its being possible to affirm that crown size affects the diametrical growth of trees. DBH and bark thickness were also significantly correlated, in so far as trees with a wider diameter possess thicker bark. It was possible to select clones with better potential for sawed timber production, that is to say, elevated DBH with a reduced LRD.
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