Introduction

For almost twenty years, the appearance of a large number of sometimes radical new transgenic crop traits has supposedly been just around the corner, but none of these ‘wonder products’ has yet made it to large-scale commercial cultivation. One of the commonest criticisms of the agbiotech industry is that a few companies precipitously commercialised a narrow set of relatively trivial input traits in the mid-1990s, rather than waiting to develop a wider range of consumer-friendly product traits. In this chapter, we survey the new generation of transgenic traits now being developed, their prospects for success, and some possible alternative non-transgenic strategies to generate the same traits in commercial and subsistence crops. We will consider two categories of traits, namely: input traits, which affect how the crop is grown without changing the nature of the harvested product; and output traits, which change the quality of the crop product itself, e.g. by altering starch, protein, vitamin or oil composition.

Input traits

Almost the entire current portfolio of commercial transgenic crop varieties contains modifications to either or both of just two input traits: herbicide tolerance and/or insect resistance. However, these two examples are far from the most important yield-limiting input traits in most farming systems around the world. More important yield traits relate to other types of biotic (from other living organisms) or abiotic (from the non-living part of their environment) stresses encountered by plants.