Plant Introduction

Plant introduction is the process of bringing a genotype from the place where it is normally grown into a new place or environment — for instance, the rice variety IR8 was introduced into India from the Philippines, and the wheat varieties Sonora 63 and Sonora 64 were introduced from Mexico. Once introduced, a plant must adjust to its new environment, a process called acclimatization. Because an introduced plant can also carry unwanted weeds, insects or disease organisms, every introduction must pass through quarantine — a strict isolation procedure that prevents the spread of disease into the new region. Introductions are of two kinds: primary introduction, where the imported variety is already well adapted to the new environment and is used without any change to its original genotype, and secondary introduction, where the imported variety is subjected to selection to isolate a superior form, which is then hybridised with a local variety to transfer one or a few desirable characters. Botanical gardens have historically played an important role in this process — tea varieties collected from China and North-East India, for example, were first grown in the Botanical Garden of Kolkata, from which suitable clones were selected and distributed across India. In India, the National Bureau of Plant Genetic Resources (NBPGR), headquartered at Rangpuri, New D …