Extreme nickel hyperaccumulation in the vascular tracts of the tree Phyllanthus balgooyi from Borneo

Abstract

SummaryPhyllanthus balgooyi (Phyllanthaceae), one of > 20 nickel (Ni) hyperaccumulator plant species known in Sabah (Malaysia) on the island of Borneo, is remarkable because it contains > 16 wt% Ni in its phloem sap, the second highest concentration of Ni in any living material in the world (after Pycnandra acuminata (Sapotaceae) from New Caledonia with 25 wt% Ni in latex).This study focused on the tissue-level distribution of Ni and other elements in the leaves, petioles and stem of P. balgooyi using nuclear microprobe imaging (micro-PIXE).The results show that in the stems and petioles of P. balgooyi Ni concentrations were very high in the phloem, while in the leaves there was significant enrichment of this element in the major vascular bundles. In the leaves, cobalt (Co) was codistributed with Ni, while the distribution of manganese (Mn) was different. The highest enrichment of calcium (Ca) in the stems was in the periderm, the epidermis and subepidermis of the petiole, and in the palisade mesophyll of the leaf.Preferential accumulation of Ni in the vascular tracts suggests that Ni is present in a metabolically active form. The elemental distribution of P. balgooyi differs from those of many other Ni hyperaccumulator plant species from around the world where Ni is preferentially accumulated in leaf epidermal cells.

Ultramafic geoecology of South and Southeast Asia

“…Nuclear microprobe imaging (micro-PIXE) shows that in P. balgooyi collected from ultramafic soils in Sabah, Malaysia, Ni concentrations were very high in the phloem of the stems and petioles, while in the leaves Ni was enriched in the major vascular bundles (Mesjasz-Przybylowicz et al 2015). The preferential accumulation of Ni in the vascular tracts suggests that Ni is present in a metabolically active form.…”

“…‘bambangan’TreeSabah, Malaysia16,700––––Van der Ent et al (2015f)Phyllanthaceae Glochidion sp. ‘nalumad’TreeSabah, Malaysia9000––––Van der Ent et al (2015f)Phyllanthaceae Phyllanthus balgooyi TreeMalaysia and Philippines8610––––Hoffmann et al (2003), Mesjasz-Przybylowicz et al (2015)Phyllanthaceae Phyllanthus erythrotrichus ShrubZambales, Philippines17,520––––Quimado et al (2015)Phyllanthaceae Phyllanthu s securinegioides ShrubSabah, Malaysia23,300––––Baker et al (1992), Van der Ent et al (2015f)Phyllanthaceae Phyllanthus sp. undet.ShrubSri Lanka–821–––Rajakaruna and Bohm (2002)Piperaceae Peperomia pellucida ShrubSulawesi, Indonesia–300–––Brooks et al (1978)Rubiaceae Psychotria cf .…”

X‐ray elemental mapping techniques for elucidating the ecophysiology of hyperaccumulator plants

“…Two options have been successfully applied so far: (1) collecting whole live plants with soil in the field and rapid transport to a cryo‐preparation laboratory (e.g. Koosaletse‐Mswela et al ., ); or (2) cryo‐fixing specimens in the field using metal‐mirror impact freezing and transport to a laboratory in a cryoshipper (Mesjasz‐Przybyłowicz et al ., , Van der Ent et al ., ). Cryoshippers maintain liquid nitrogen temperature (dry vapour) for several days without refilling and are International Air Transport Association‐approved for air transport.…”

“…Tylko et al, 2007a,b;Wang et al, 2013b), or water can be removed by very slow temperature-controlledfreeze-drying (lyophilisation) (e.g. Mesjasz-Przybyłowicz et al, 2016).…”

The discovery of nickel hyperaccumulation in the New Caledonian tree Pycnandra acuminata 40 years on: an introduction to a Virtual Issue

“…The tissue‐level micro‐distribution of nickel has been elucidated in several hyperaccumulator species in Alyssum, Berkheya, Hybanthus, Noccaea, Phyllanthus and Senecio (for examples, see Mesjasz‐Przybylowicz et al ., , , , ; Broadhurst et al ., ; Küpper et al ., ; Kachenko et al ., ). In most hyperaccumulators nickel is preferentially accumulated in foliar epidermal cells, but in Berkheya coddii from South Africa it is found mainly in the mesophyll and vascular bundles (Mesjasz‐Przybylowicz et al ., ).…”