Abstract:

1-aminocyclopropane-1-carboxylic acid synthase is one of the key rate-limiting enzymes for ethylene biosynthesis in higher plants. Based on the cloning of Sc-ACS1, Sc-ACS2 and Sc-ACS3 of ACS gene families, their expressions were tested in the roots and leaves of sugarcane with Sc-ACS1, Sc-ACS2 and Sc-ACS3 as the probes, respectively. The results of Northern blotting analysis showed that the expression of Sc-ACS1 was induced by ethephon in leaves, but not in roots; that of Sc-ACS2 in leaves and roots; and that of Sc-ACS3 in roots, while not in leaves. Under the environmental stresses（cold stress, dark-growing condition and LiCl stress）and hormone inducement (IAA), the mRNA of Sc-ACS1 showed a higher expression while that of Sc-ACS2 maintained low expression level in leaves.

Key words: Saccharum officinarum L. Hybrid, 1-aminocyclopropane-1- carboxylic acid synthase, Gene family, Expression