REGULAR ARTICLE Leaf silicon content in banana (Musa spp.) reveals the weathering stage of volcanic ash soils in Guadeloupe C. Henriet & L. Bodarwé & M. Dorel & X. Draye & B. Delvaux Received: 3 March 2008 / Accepted: 4 June 2008 / Published online: 26 June 2008 # Springer Science + Business Media B.V. 2008 Abstract Several plant species accumulate silicon, which is taken up by roots in soil solution. The Si concentration in soil solution can be governed by silicate dissolution and formation, and thus soil constitution. Here, we study the Si leaf content of mature banana plants (Musa acuminata cv Grande Naine) cropped on soils derived from andesitic ash in Guadeloupe through standard foliar analysis. The soils strongly differ in weathering stage and total Si content. The most desilicated soils (Andosol–Nitisol– Ferralsol) occur in the wettest areas, on the Eastern slopes (Es) of the volcano exposed to rain bearing winds. Least weathered soils (Andosol–Cambisol) occur on Western slopes (Ws). The average leaf Si concentration ranges from 2.7 to 3.9 g kg -1 for bananas cropped in Es soils, and from 7.7 to 9.6 g kg -1 in Ws soils. The leaf Si concentrations are lowest for the Es gibbsite-rich Andosols and Ferralsols. The leaf Si concentration is positively correlated with soil CaCl 2 - extractable Si content, soil Si content and total reserve in weatherable minerals. The silicon content of banana leaves thus reveals the weathering stage of volcanic ash soils in Guadeloupe. Keywords Silicon . Musa . Foliar diagnosis . Soil weathering . Transpiration Introduction Silicon plays a crucial role in global biogeochemical processes such as the regulation of carbon dioxide (Berner 1995; Kump et al. 2000), the buffering of proton fluxes through silicate dissolution (Rai and Kittrick 1989), and the nutrition of both marine and terrestrial biota (Smetacek 1999). Since the rates of mineral dissolution can be enhanced by plant impact on silicate weathering (Moulton et al. 2000), plants can exert a strong imprint on the Si continental cycle, and thereby on Si release to water streams (Derry et al. 2005). Several plant species readily accumulate silicon, which is, however, not considered as an essential plant nutrient (Epstein 1994). Si-accumula- tors are mostly monocots (Ma and Takahashi 2002). Plant Soil (2008) 313:71–82 DOI 10.1007/s11104-008-9680-7 Responsible Editor: Jian Feng Ma. C. Henriet : L. Bodarwé : B. Delvaux (*) Soil Science Unit, Université Catholique de Louvain, Place Croix du Sud 2/10, 1348 Louvain-la-Neuve, Belgium e-mail: bruno.delvaux@uclouvain.be M. Dorel Département des productions fruitières et horticoles, Centre de coopération internationale en recherche agronomique pour le développement (CIRAD), Station de Neufchâteau, Capesterre-Belle-Eau, Guadeloupe X. Draye Crop Physiology and Plant Breeding Unit, Université Catholique de Louvain, Place Croix du Sud 2/11, 1348 Louvain-la-Neuve, Belgium