Relation of chlorophyll and foliar nitrogen of Gmelina arborea Roxb. at the nursery and in the field

Abstract

The fundamental role that Gmelina arborea (melina) has reached to guarantee the supply of raw material for the forest industry, in the tropical and sub-tropical areas, highlights the need to find superior genotypes; for this, the parameter (s) that will be used as a reference in a possible selection at early stages, must necessarily be associated to the development of the material in the field. The objective of the present investigation was to identify differences between G. arborea clones in their chlorophyll content, obtained in the laboratory and through the portable SPAD meter and thus determine correlations with their performance in a one-year-old plantation, and their potential for the early selection of superior genotypes of this species. Clones 8 and 3 recorded the extreme values in the chlorophyll content. The value of the correlation between SPAD and total chlorophyll in the laboratory was 0.52, which is considered moderate for forest species. Clones 10 and 12 reached the highest correlation figures between SPAD-DAP and SPAD-total volume, which opens the possibility of being able to select clones that will have better performance in the field from the chlorophyll reading in the nursery stage, obtained by the portable meter. However, it is necessary to develop and validate a methodology for obtaining chlorophyll content at early ages for the species.