The cultivation of improved and stress resistant varieties plays an important role in enhancing and sustaining the crop productivity of a particular area. The varietal technology is simple to adopt, economically viable, eco-friendly and socially acceptable for attaining higher productivity. The Andaman & Nicobar Islands being listed as hope spots by International Union for Conservation of Nature (IUCN) also figure among 22 agro-biodiversity hotspots in India. Climate change is another looming threat which is perceived to affect islands more as compared to mainland. Of the 576 Islands, only about 30 are inhabited and of the total geographical area, only about 5-7 % is under agriculture due to ecological considerations. The population increase and tourist influx require increase of local production in eco-friendly way. Therefore scope for area expansion for agri- horticultural cultivation is minimal and thus vertical growth of productivity is the only option. The tropical warm and humid climate of the islands also favours infestation of crops by diseases and insect pests. In addition, "Organic agriculture" relying on zero or minimal application of chemical inputs is advocated as the viable approach for protecting the sensitive marine and terrestrial biota from the ill- effects of harmful chemicals.
Under such a challenging scenario, the selection, development and adoption of island- specific varieties possessing higher yield, resistance/ tolerance to various biotic and abiotic stresses with other acceptable traits are important steps for reaping higher productivity and economic gains in a sustainable manner. In this regard, ICAR-CIARI Port Blair, has developed about 30 varieties of various field and horticultural crops which include resistant varieties for bacterial blight in rice and bacterial wilt in brinjal. Most of these varieties are derived from the locally adapted germplasm material through collection and pure line selection, which enhances their scope of adoption and adaptation in the islands. In addition, a talc based microbial consortia (CIARI Bioconsortia) derived from indigenous Bacillus species has been developed for the eco-friendly management of bacterial wilt in solanaceous vegetables. Efforts are being made to disseminate and popularize these eco-friendly technologies for achieving higher agricultural productivity in a sustainable manner.