Shading levels on production and development of Eucalyptus grandis Hill ex Maiden seedlings

Reginaldo Fereira Santos, Leandro Morais, Augustinho Borsoi, Deonir Secco, Gláucia Cristina Moreira

Abstract


The goal of the work was to assess the influence of shading levels on seedling production of Eucalyptus grandis. The seedlings have been subjected to treatments: 0%; 18%; 30%; 50% and 70% attenuation of solar radiation through screens of polyolefins black coloring. The experiment was performed in autumn 2009 in the city hotbed of Catanduvas – PR, during a period of 90 days. The experiment design was randomized block, with five treatments and five replications. The pricking-out of sowing seedlings for tubes occurred on the 30th day after sowing. At 90 days it was evaluated: shoot height, number of leaves per plant, collar diameter, root length, fresh and dry leaf, root and collar. For all dendrometric variables evaluated, the effect of the treatment was significant. For shoot height, treatments of 30 and 50% shading were higher than the other. Collar diameter and number of sheets, processing the full sun presented the greatest values (0.20 and 15.20, respectively). For variable dry mass and fresh sheets, collar and root treatment with 30% of shading was statistically superior to the others. 30% attenuation of solar radiation has higher dendrometrics characteristics of seedlings to the variables analyzed for E. grandis.


Keywords


Attenuation; transplantation; solar radiation; forest population



DOI: https://doi.org/10.5777/paet.v3i3.1154