Variation in foliar elemental composition in mature wild trees and among families and provenances of Vochysia guatemalensis in Costa Rica
1997
Gonzalez, E. | Fisher, R.F.
Variation in foliage elemental composition provides insights into the adaptive mechanisms of species to a particular site and provides the bases for selection for greater nutrient use efficiency. Studies of this variation in tropical trees have been limited to a small number of species, mainly pines and eucalypts. This study compared the foliage elemental composition of mature trees of Vochysia guatemalensis D. SMITH from 3 sites in Costa Rica. At each site foliar and soil samples were collected individually per tree and analyzed for elemental composition. Differences in foliar P, Mg, Fe, Cu, Zn and Mn were found among sites. No significant nor consistent correlations were found between soil chemical properties and tissue elemental composition. Even though there were large differences in pH and cation exchange capacity among sites, tissue Ca (mean 12.4 g kg(-1)) and Al (20,100 mg kg(- 1)) content did not vary significantly. In order to assess the variation in foliage composition among provenances and families within provenances, a progeny test planted on an acidic, infertile Inceptisol was studied. For the 6 provenances planted, 3 families and 2 trees per family were randomly selected and individually sampled for foliage and soils. At 4 years of age, significant differences among provenances and families were found for P concentration, varying from 0.42 g kg(-1) for the Siquirres provenance (Costa Rica) to 0.52 g kg(-1) for La Ceiba provenance (Honduras). For Ca,Mg, Al, and Zn only differences among families within provenances were detected. Foliar Fe concentration was found to differ significantly only among provenances. Even though no final conclusions about genetic differences in elemental composition among families and provenances of this species can be made due to the small number of provenances and families sampled, these findings indicate that genetic differences in foliage elemental composition occur, suggesting that genetic differences in response to nutrient availability carl also be expected.
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