Abstract:Poplars (Populus) are one of the most important deciduous trees in the world. China is rich natural resource of poplars. Poplars have fast growth rates, high yields, wide uses and are easy for tissue culture and have small genomes that make them well suited as model plants for the studies of tree physiology and genetic engineering. Recently, much progress has been made in the freezing_resistance of
poplars which covers the character and indexes of physiology and biochemistry, selection of natural hybrids, and artificial crossbreeding. This paper reviews these advances in the fields and evaluates the applications of genetic engineering in improvement of freezing tolerance of poplars.