s:3482:"%T Root architecture of the promising bio-diesel plant Jatropha %A Achten, W.M.J. %A Reubens B %A Maes W H %A Mathijs E %A Verchot J %A Singh V P %A Poesen J %A Muys B %X Jatropha curcas L. (Euphorbia ceae) receives a lot of attention as a sour ce of renewable energy. The drought resistant , oil bearing small tree is well adapted to tropical semi-arid regions and marginal sites. As a pioneer spe-cies , originating from Central America ,but now growing pantropic, J. curcasis easily propagated and can establish quickly in a wide variety of soils , al-though the plant suffers immediately fro m frost and waterlogging (Heller , 1996 ). The J .curcas seeds contain 30 -35% in edible oil which can be easily converted to bio -diesel that meets the American and European standards (Azam et al., 200 5). The bio -diesel production chain also results in some valuab le by- products (e.g. seed cake , fruit husk s, glycer in ) (fig. 1). Next t o t h e b io-d ie s e l t h e p la n t is a ls o u s e fu l a s livin g fe n ce . S in ce J . cu rca s is n ot b r ows ed , t h efen c e s ca n b e u s e d t o p r ot ec t foo d c r op p r od u c tion (Gubitzeta l.,1999 ). F u r t h er t h e fen ce s a r e u s ed fo r e co lo gic a l r e s t or a t ion o f d e gr a d ed a r e a s (Za h a wi, 2 0 0 5 ). J . cu rca s c u lt iva t ion is a ls o r ep or t e d t o p r e ve n t a n d co n t r o l e r os ion (G u b it z e t a l. , 1 9 9 9 ), a lt h ou gh n ot b a s e d on s c ie n t ific d a t a .Th e p r ot e ct ive r ole of ve ge t a t io n h a s b een p r ove n in m a n y s t u d ies a n d e s p e-cia lly p la n t r oot s co u ld p la y a n im p or t a n t r ole in s lo p e s t a b iliza t ion a n d e r o-s ion con t r o l (Ab e & Ziem e r , 1 9 9 9 ; Co u t t s , 1 9 8 3 ). Alt h ou gh s t ill a h yp ot h e s is , J . cu rca s p r ob a b ly c ou ld b e u s e d s im u lt a n eou s ly for b io-d ie s e l p r od u ct ion a s well as eros ion control in tropical areas . In this cont ext t h e r e is a n e ed fo r s c ien t ific r e s e a r c h t o b et t er u n d e r s t a n d t h e e ffe ct s of t h is s p e cie s a n d it s r oo t s o n geom or p h o logic p r oc es s es . In gen e r a l, a s is t h e c a s e wit h m a n y p la n t s p e c ie s , b e lowgr o u n d s t r u c t u r a l a n d fu n c t io n a l d e ve lop m e n t o f J . cu r-ca s h a s r e c eived ver y lit t le a t t en t io n s o fa r , m a in ly a s a c on s e q u e n c e of m e t h od o lo gic a l d ifficu lt ie s (G ys s e ls & Poe s e n , 2 0 0 3 ; Wa is e l e t a l. , 2 0 0 2 ). Ne ver t h ele s s , in or d e r t o s u s t a in a b ly gu id e t h e b oom in g u s e of t h is p r om is -in g s p e c ie s , it is im p or t a n t t o a ls o fu lly u n d er s t a n d it s b elowgr ou n d a s m u ch a s it s a b o ve gr ou n d fu n ct ion a l a n d s t r u ct u r a l d e ve lop m e n t . Be s id es t h e s t a -b ilis in g r o le m e n t ion ed b efor e , a n o t h e r p r im a r y r o le of r oo t s is off cou r s e t h e u p t a k e a n d s t or a ge of wa t er a n d n u t r ie n t s (G r egor y, 2 0 0 6 ). S u m m a r is ed , t h e m a in r e a s on s for s t u d yin g r oo t s a r e ecolo gica l s ign ific a n ce , r e s o u r ce c a p t u r e a n d a lloc a t ion , c a r b on flow, p la n t in t e r a ct io n s , effect o n s o il s t r u ct u r e , a n -ch o r a ge, u s e of r oot p r od u c t s , a s well a s s im p ly b a s ic b iologic a l in for m a t ion ";