Acknowledgements

Sajid Hussain is thankful to China National Rice Research Institute for the necessary facilities and to Chinese Academy of Agricultural Sciences, China for the award of Postdoctoral Fellowships. SH is giving special thanks to Prf. Dr. Qianyu Jin and Junhua Zhang for motivated me to write this chapter and provided my friendly environment to complete this task. We are also highly thankful to Dr. M. Ashraf and M. Shaukat, for contributing in chapter write up and providing us supporting material.
