Purpose of plant introduction

a) To Obtain an Entirely New Crop Plant: Some recently introduced crops are Soybean, gobhi sarson, oil palm etc.

b) To Serve as New Varieties: The Mexican semidwarf wheat varieties Sonora 64 and Lerma Rojo, semidrawf rice varieties TN 1, IR-8 and IR-36 are more recent examples of this type.

c) To Be Used in Crop Improvement: Often the introduced material is used for hybridization with local varieties to develop improved varieties. Pusa Ruby tomato was derived from a cross between Meeruty and Sioux, an introduction from U.S.A.

d) To Save the Crop from Diseases and Pests: Coffee was introduced in South America from Africa to prevent losses from leaf rust.

e) For Scientific Studies: Collections of plants have been used for studies on biosystematics, evolution and origin of plant species.

f) For Aesthetic Value: Ornamentals, shrubs and lawn grasses are introduced to satisfy the finer sensibilities of man. These plants are used for decoration and are of great value in social life.

g) Varieties Selected from Introductions: Two varieties of wheat, Kalyan Sona and Sonalika, were selected from introductions from CIMMYT, Mexico.

h) Varieties Developed through Hybridization: All the semidwarf wheat varieties are derived from crosses with Mexican semi-dwarf wheats. All but few semidwarf rice varieties possess the dwarfing gene from Dee-geo-woo-gen through either TN1 or IR 8. Thus, almost all these semi-dwarf wheat and rice varieties have been developed from crosses involving introductions. All the sugarcane varieties have been derived from the introduced noble canes.