GM Maize for Abiotic Stresses: Potentials and Opportunities

Abstract

Maize is one of the major staple foods in the world, along with other cereals such as wheat, rice, and sorghum. Apart from this, maize is also a plant for science and technology. Many basic and applied phenomena are discovered and applied by using this plant to prove their worth before generalization. Hybrid seed production, which is a well accepted breeding technique now, was identified and practically applied on maize to significantly enhance per unit area production. Genetically modified (GM) crops were introduced for the first time in the world in 1995, and now approximately 200 million hectares of GM crops are grown in 26 countries of the world. Bt maize, herbicide-tolerant soybean, and Bt cotton were among the pioneering crops harboring this technology. Since the introduction of GM technology, continuous efforts are going on to develop GM maize to improve various agronomic, quality, and value addition traits. Imparting stress tolerance is of utmost importance in maize and other cereals. Under the climate change scenario, abiotic stress tolerance has gained major importance. There may be emergencies for eradicating weeds because of sudden rains, drought may be established by the unavailability of water for a week, and temperature fluctuations may establish stress from heat or frost. Maize, being a C4 plant, needs a continuous supply of nutrients and water for its extensive photosynthesis. When there is any interruption to such supply of water and nutrients, plants experience stress, which may result in complete crop failures within a short span of time. In this chapter we have tried to impart the importance of maize in food security and energy production and how abiotic stresses can affect crop performance. We also analyzed techniques being used for maize transformation, and how resolution of various stresses is being tried using this technology, to see potential opportunities for improving the quality and production of maize.