© 1995 Heron Publishing—Victoria, Canada
Aluminum sensitivity of loblolly pine and slash pine seedlings grown in solution culture
Jaroslaw Nowak and Alexander L. Friend
Department of Forestry, Mississippi State University, Box 9681, Mississippi State, MS 39762-9681, USA / Received June 16, 1994
Summary
To probe variation in Al sensitivity of two co-occurring pine species, seedlings from six full-sib families of loblolly pine
(Pinus taeda L.) and slash pine (Pinus elliottii Engelm.) were grown in solution culture containing 4.4 mM (high-Al) or 0.01 mM (low-Al) AlCl3 at pH 4 for 58 days. On average, both pine species had 41% less total dry weight in the high-Al treatment than in the low-Al
treatment. Stem volume growth of slash pine was more sensitive to the high-Al treatment than that of loblolly pine. In both
species, the high-Al treatment inhibited root dry weight more than shoot dry weight. Within-species variation in Al sensitivity
among families was greater in loblolly pine (24 to 52% inhibition of seedling dry weight) than in slash pine (35 to 47% inhibition
of seedling dry weight). Foliar Al concentration was positively correlated with Al sensitivity in slash pine but not in loblolly
pine; however, in both species, the concentration of Al in roots was 20-fold greater than in foliage.
Keywords:
aluminum tolerance, genetic variation, Pinus elliottii, Pinus taeda.
