Production of Transgenic Vegetable Brassicas

Abstract

Vegetable brassicas are economically important and grown worldwide for consumption as both fresh and frozen produce. Brassica oleracea contains 14 vegetable species with practically every part of the plant used including the leaves (cabbage), axillary buds (Brussels sprouts), stems (kohlrabi), floral primordial (cauliflower) and flower buds (broccoli). B. campestris contains green leafy vegetables such as pak choi and Chinese cabbage. They are highly nutritious, particularly broccoli which contains high amounts of calcium, carotene, vitamin C and vitamin A. In addition, vegetable brassicas are gaining in popularity as they contain compounds with anti-cancer properties. However, they are susceptible to attack from several insect pests and to infection by a range of bacterial and fungal diseases. In addition, post-harvest deterioration can limit shelf-life. Genetic engineering (GE) technology offers the opportunity to produce pest- and disease-resistant varieties by enabling the transfer of genes that would not be possible by conventional breeding methods. An advantage of GE is that a small amount of well-characterized DNA can be quickly added to elite lines. This DNA can be from any source; plant, animal, bacterial, viral or artificially synthesized. Since the first reports of transgenic vegetable brassicas in the late 1980s, GE of vegetable brassicas has now progressed to the stage where agronomically useful traits have been introduced and numerous plants have been field-tested. However, no commercial release of a transgenic vegetable Brassica cultivar has yet occurred.