Utilization of wild germplasm for vegetable improvement a review

Abstract

About 400 species constitute the total diversity in vegetable crops across the globe. Among the diversity rich regions of the world that represent the centers of origin and /or diversity as well the regions possessing maximum diversity are the tropical American, Tropical Asian and the Mediterranean region. In the tropical Asian region, both India and China hold maximum diversity. Nearly 80 species of major vegetables, apart from several wild/undomesticated types are native to Indian region and are mentioned under “Hindustani Centre”. India has a long history of vegetable cultivation and Sanskrit equivalents are available for introduced vegetable crops indicating exchange of plant material with other countries well before the Christian Era e.g. bottle gourd and watermelon from Africa, and onion from Central Asia. Other species, having wide distribution in India are, Trichosanthes, Momordica, Coccinia and Canavalia etc. Overall, 20-25 vegetable crops are commercially important and these include both the indigenous and exotic species. Germplasm acquisition from within and outside country is the first step in germplasm management programme. A large germplasm representing a broad spectrum of genetic diversity has been introduced from other countries.  Several introduced varieties have been used directly for large-scale cultivation. Many introductions in vegetable crops have also been used as parents to develop new cultivars. Germplasm of wild species of crops like brinjal (47), chilli (87), okra (82), tomato (385), water melon (18) have been introduced by NBPGR from abroad in the past few years. Besides identifying donors form cultivated form, their wild allies called CWR does have valuable genes with immense value for crop improvement and adaptation to changing environmental conditions. Utilization of CWR has enjoyed a great success in few crops like okra, tomato, potato, cucumber.