Nitrate-uptake restraint in Banksia spp. (Proteaceae) and Melaleuca spp. (Myrtaceae) from a severely phosphorus-impoverished environment

Abstract Aims South-western Australia has some of the most phosphorus (P)-impoverished soils in world. Hakea prostrata (Proteaceae) nitrate (NO 3 − )-uptake restraint, associated with its high P-use efficiency. This research explores how common this trait is other Proteaceae and co-occurring plant species south-western Australia. Methods Banksia attenuata (Proteaceae), B. telmatiaea Melaleuca seriata (Myrtaceae) M. rhaphiophylla were grown no NO , Medium (500 µM) or High (2500 treatments source nitrogen (N). Plants harvested after treatments. Leaf phosphate concentrations determined, as well biomass, total N P leaves, stems roots separately. Results had similar content when supplied they did . All four same low leaf -N concentration treatments, more than 6% N. those plants growing their natural habitat where available soil was much lower. These results are sharp contrast that typically studied, for example Arabidopsis thaliana Conclusions exhibited -uptake restraint to different degrees. Nitrate-uptake appears a convergent many evolved severely P-impoverished landscapes, allowing them be P-efficient.