EFFECTS OF GA3 ON THE DEVELOPMENT AND THE ABSORPTION OF NUTRIENTS AND HEAVY METALS IN LETTUCES (Lactuca sativa L.)

Abstract

This paper investigated the influence of GA3 on the development and heavy metals’ absorption in
Lettuces (Lactuca sativa L.). Lettuces were exposed with GA3 at different concentration of 0, 10, 30, 50
and 100 mg L-1
, respectively, at the 7-day, the 14-day, and the 21-day after transplanting. Several
parameters as the height, number of leaves, and fresh weight of lettuces were studied. In addition, the
concentrations of metals such as Fe, Mn, Pb, Cd, Se, Sn, Hg, and Cr in lettuce tissues were measured.
The results indicated that low concentrations of GA3 (10 and 30 mg L-1
) increased the plant height,
number of leaves and fresh weight of lettuces, whereas the opposite results were reported in high
concentration of GA3 treatment (100 mg L-1
). On the other hand, GA3 decreased nutrient contents of Fe
and Mn, and heavy metals’ absorption in lettuces. This is the first study of the effects of GA3 on nutrient
contents and the absorption of heavy metals in lettuces, which should be further investigated to improve
agricultural production efficiency using GA3 and minimize the harmful impacts of heavy metals on
human health and environment.