ABSTRACT
The world population is growing and is forecast to reach around 9 billion by 2050 and more than 10 billion by 2100 according to a United Nations press release of May 2011. The competition for land by a myriad of users means that land available for agriculture is likely to decrease despite technological improvements that might extend the boundaries of land that can support agriculture. Therefore, with the population continuing to increase farmers must try to produce more from less land while at the same time protecting the environment and ensuring food security. Recent research has suggested that the global demand for cereals will increase by 75 per cent between 2000 and 2050 (IAASTD, 2008). A larger world population increases the challenges we face to manage land in such a way so as to sustain it and the wider environment in a healthy condition for future generations. Much of the progress in increasing yields to meet the growing population and also higher standards of living in many parts of the world in the middle part of the twentieth century stemmed from improvements in crop varieties bred to give larger yields and produce less waste, for example straw from cereals (Gale and Youssefian, 1985).
