Abstract

Enhancement of Cellulose Content in Eucalyptus tereticornis through Genetic Transformation

M S Reddy, Professor, Thapar University

Paper is always an important commodity for the society and is produced from wood of selected plant species. Wood is processed to pulp through kraft pulping by removal of lignin. During kraft pulping large amount of chemicals are used causing environmental hazards and higher amount of lignin in wood also reduces the yield of pulp. It has been estimated that a small decrease in the percentage of lignin (about 5%) or increase in cellulose content is likely to increase the yield of pulp and also reduce the cost of pulping, which could significantly benefit the pulp and paper industry. This could be achieved either through downregulation of important genes of lignin synthesis or overexpression of key genes of cellulose biosynthesis in target plants used for production of pulp. For over expression of cellulose biosynthesis two key genes have been identified namely, sucrose synthase (provide the substrate i.e. UDP-glucose for cellulose synthesis) and Korrigan (involved in editing of growing cellulose chains and thus increases the crystallinity of produced cellulose). Present work focuses on the upregulation of these two genes in important plants species namely, Populus deltoides and Eucalyptus tereticornis, which are used as raw material for pulp and paper industry. An efficient shoot organogenesis and genetic transformation using Agrobacterium tumefaciens harbouring binary vector pBI121 have been achieved for both the species. Shoot organogenesis has been achieved using leaf explants taken from microshoots. Further transformation of E. tereticornis with korrigan gene has been achieved. Four transgenic lines expressing korrigan gene have been developed and characterized using various molecular tools. Work is in progress to transform P. deltoides.