Fruit is dear in France on the railway (6)
I believe the answer is:
cherry
'fruit' is the definition.
(cherry is a kind of fruit)
'dear in france on the railway' is the wordplay.
'dear in france' becomes 'cher' (French term of endearment).
'on' is a charade indicator (letters next to each other).
'the railway' becomes 'ry' (abbreviation for railway).
'cher'+'ry'='CHERRY'
'is' is the link.
(Other definitions for cherry that I've seen before include "The colour of a red fruit" , "Red liqueur" , ""Loveliest of trees, the ____ now" (Housman)" , "Small red stone-fruit from tree" , "Greyfriars boy identified" .)