Clue: Current wanted for cultivation of arid region? (3,6)
Answer: RIO GRANDE
Explanation: Definition: Current wanted for cultivation of arid region
 "i"(symbol for electric current in physics) **deleted from**(wanted for/found wanting in) **anagram of**(cultivation of) "arid region".
Answer: …, a river in southwestern USA and northern Mexico that flows through arid and semi-arid land.