ABSTRACT
Rice (Oryza sativa L.) is the major staple food crop in the world, feeding more than 50% of the world’s population (Verma et al., 2012, 2013, 2015). Rapid increase in the human population together with acute weather conditions leading to biotic and abiotic stresses demand for a sustainable improvement of crop varieties including rice. Conventional rice improvement methods such as cross hybridization and mutation breeding techniques are gradually getting inhibited by the declination of the existing genetic variability thereby affecting the production for future supply (Chen and Gao, 2014). Molecular marker-assisted selection has the advantage of detecting constructive agricultural characters. However, large dependence on traditional crossing and backcrossing approaches for pyramiding of agriculturally important traits makes the process both times consuming and labor-intensive for rice improvement. Moreover, high variability in the stress factors often leads to rapid breakdown of stress response in the rice varieties with the course of time (Jia, 2003). Foreign gene transfer into plant genome has been a focal point of crop improvement for the last two decades. There are many examples
of transgenic rice with improved traits such as enhancement in nutritional quality or resistance to insects, pathogens or herbicides (Chen et al., 2009). However, the concern of the general public and the environmental protection agencies over the cultivation of crop with foreign genes from distantly related organisms is a major hindrance to their widespread use. The adherence to the regulatory frameworks for environmental protection and addressing the public concerns has added to the cost of transgenic development (Lusser et al., 2012). As such, there are only a few transgenic crops such as soybean, corn and cotton with agriculturally valuable traits that are available for human use.
