A harsh, restricted lifestyle in productive industry (11)
I believe the answer is:
agriculture
'productive industry' is the definition.
(industry which produces food)
'a harsh restricted lifestyle' is the wordplay.
'harsh' becomes 'grim' (synonyms).
'restricted' means to remove the last letter (restricted can mean limited or reduced).
'lifestyle' becomes 'culture'.
'grim' with its final letter taken off is 'gri'.
'a'+'gri'+'culture'='AGRICULTURE'
'in' acts as a link.
(Other definitions for agriculture that I've seen before include "Farming science" , "The practice of farming" , "Land cultivation" , "Husbandry" .)