CONCLUSIONS
Both B. attenuata and B. sessilis exhibited a unique
pattern of allocating P to different P fractions within the leaves under
P limitation. Banksia sessilis allocated more P to nucleic acids
than B. attenuata . This investment in nucleic acid may support
greater protein synthesis, which is likely needed for greater protein
turnover.
The observations that B. attenuata had a higher LMA and lower N
concentration, PPUE, allocation of P to nucleic acids and N:P ratios
than B. sessilis are possibly adaptive traits to growth in more
severely P-impoverished soils, and may account for the different
distributions of the two species. We surmise that P-allocation patterns
are likely the functional basis explaining why plants can reduce foliar
P concentrations on P-poor soils. The foliar nutrient-allocation
patterns and distinct foliar traits of the two Banksia species
reveal different adaptive strategies in response to soil P availability
and match their differences in growth strategies.