This book entitled ''Introductory Crop Physiology'' is primarily intended for the use ICARs and BHU B.Sc.(Ag.) M.Sc.(Ag.) and SAUs and other competitive examinations is very useful. This book has been complied on the basis of vast experience of the Author in the field of competitive examinations. The Author are greatly thankful especially to Dr. A. H. Khan (HOD), Dr. A.K.Singh, Dr. Uma Singh, Dept. of Crop physiology , NDUA&T Ayodha (U.P.) Suggestions of all readers and students are always welcome.