The effect of aluminium on the growth of a range of temperate legume species and cultivars: A summary of results

Abstract

The aluminium (Al) tolerance of 35 temperate legumes (136 accession lines or cultivars) was determined in 74 experiments over a 2 year period in a low ionic strength (2730 µM) solution culture. For each cultivar, the relationship between solution Al3+ activity (µM) and relative root yields was determined using polynomial exponential splines and the Al3+ activity associated with a 50% reduction in root yield (AlRY 50) was calculated. All species tested in the genera Adesmia, Medicago and Melilotus tended to be very sensitive to aluminium (AlRY50 >1). Dorycnium pentaphyllum was sensitive whereas AlRY50 of the lines from the species D. hirsutum ranged from 1.4 to 2.4 (mean 1.9). In Lotus and Trifolium, the order of tolerance for each species (based on the AlRY 50 meaned over lines) was L. tenuis, T. resupinatum (AlRY 50 >0.5) > T. balansae, T. fragiferum, T. hybridium and T. pratense (AlRY50 0.5–1) > L. angustissimus, L. corniculatus, L. subbiflorus, T. ambiguum, T. dubium, T. glomeratum (AlRY 50 1–1.5) > T. amabile, T. repens, T. semipilosum, T. striatum, T. tumens (AlRY50 1.5–2) > T. medium, T. polymorphum (AlRY50 2–3) > T. subterraneum (AlRY 50 3–4) > L. pedunculatus (AlRY 50 <4). Significant differences in Al tolerance between the lines were noted for (with the range in AlRY 50 in parenthesis) Trifolium amabile (0.1–2.6), T. ambiguum (0.8–1.6), T. medium (1.5–4.1), T. repens (0.6–3.1), T. polymorphum (1.5–2.6), T. semipilosum (1.2–2.0) and T. subterraneum (1.8–5.9).