Depreciation rates under IT Act

It would help if you refer the IT ready reckoner where there is a detailed table of IT depreciation rates

 I am a Ca final student. wanna know what rate of depreciation in respect to accounts of a Tea manufacturing unit will be charged on following items:

1. Fencing of Factory.. 2. Plant and Machinery in a tea industry. 3. Commercial Vehicles. 4.Land & Plantations.

FENCING:- NOT A CAPEX CHARGE TO REVENUE

PLANT & MACHINERY:- 15% AS PER IT AND GENERAL RATE FOR CONTINIOUS FACTORY AS PER COS ACT.

COMM VEH:- 30% AS PER IT

LAND :- NIL

PLANTATION:- BASED ON UPROOTING OF TEA BUSHES 

AS

hi , i wanna  know about the rates of deprecitaion for lab instruments involved in research . as per Companies Act 1956 & also as per IT Act