Genetic Engineering of Cytokinins and Their Application to Agriculture

Abstract

Cytokinins are master regulators of plant growth and development. They are involved in the regulation of many important physiological and metabolic processes. Recent progress in cytokinin research at the molecular level, including identification of related genes and cytokinin receptors, plus elucidation of signal transduction, has greatly increased our understanding of cytokinin actions. Although still in its infant stage, molecular breeding of crops with altered cytokinin metabolism, when combined with the transgenic approach, has shown very promising potential for application to agriculture. In this review we briefly introduce recent progress in cytokinin molecular biology, discuss applications of cytokinin genetic engineering to agriculture, and present implications and future research directions.

Keywords:

• agricultural applications
• cytokinins
• genetic engineering
• molecular breeding

ACKNOWLEDGMENTS

This work was supported by the grants from the National Natural Science Foundation of China (No. 30671043 and No. 30671134), the National High Technology and Research Development Program of China (“863” program No. 2007AA10Z101), the Natural Science Foundation of Beijing (No. 6082018), and the Innovation Project of Chinese Academy of Sciences. This paper is dedicated to Prof Cheng Tsui, a pioneer of cytokinin discovery and founder for our research group. I sincerely thank Dr. Eduardo Blumwald of University of California, Dr. Murray Boase of the Institute for Crop and Food Research Limited, New Zealand and Dr. Alexander Vainstein of the Hebrew University of Jerusalem, Israel for providing photo data, Dr. Charles Hocart of the Australian National University and Dr Joy Fleming of Wonderland Training Group, UK for critical reading of this manuscript and the anonymous reviewers for their very constructive comments.