ISSN 2375-074X
African Journal of Plant Breeding Vol. 1 (5), pp. 089-097, October, 2013. © International Scholars Journals
Review
Review article: Quality protein maize (QPM): Genetic manipulation for the nutritional fortification of maize
P. A. Sofi1*, Shafiq A. Wani1, A. G. Rather2 and Shabir H. Wani3
1Directorate of Research, SKUAST-K, Shalimar, 191121, J and K, India.
2Rice Research Station, SKUAST-K, Khudwani, India.
3Department of Plant Breeding, Genetics and Biotechnology, PAU, Ludhiana, India.
*Corresponding author. E-mail: [email protected].
Accepted 7 April, 2013
Abstract
Cereals are the only source of nutrition for one-third of the world’s population especially in developing and underdeveloped nations of Sub-Saharan Africa and South-east Asia. The three major cereals, rice, wheat and maize constitute about 85% of total global cereals production amounting to about 200 million tonnes of protein harvest annually at an average of 10% protein content, out of which a sizeable proportion goes into human consumption (Shewry, 2007). A major concern in case of developing nations is that in most cases, a single cereals crop is the major food staple and as such the nutritional profile of cereal crops assumes great significance. Grain protein content of cereals has a very narrow range with rice (5.8-7.7%), maize (9-11%), barley (8- 15%) and wheat (7-22%) as reported by various workers. In many developing countries of Latin America, Africa and Asia, maize is the major staple food and often the only source of protein. At global level, maize accounts for 15% of proteins and 20% of calories in world food diet. But unfortunately, the nutritional profile of maize is poor as it is deficient in essential amino acids such as lysine, tryptophan and methionine due to a relatively higher proportion of prolamines in maize storage proteins which are essentially devoid of lysine and tryptophan. The reason concerning this is that lysine, tryptophan and threonine are the limiting amino acids in human beings and non -ruminants. Maize is also an important component of livestock feed especially in developed nations where 78% of total maize production goes into livestock feed. Therefore, breeding strategies aimed at improving the protein profile of maize will go a long way in reducing prevalence and persistence of malnutrition in developing world.
Key words: Mucronate, protein, maize, zein.