Wednesday, August 1, 2012
Grand Ballroom
Zinc (Zn) is an essential component of many biological processes. It is a co-factor for genetic material, whereby, its deficiency may result in reduced cognitive and/or immune functions. Approximately, 30% of the world’s population is zinc deficient. Typical symptoms in humans include severe diarrhea, undersized and suppressed ailment/wound recovery. The objective of this experiment was to employ biofortification of zinc to a level below the toxicity level in fenugreek (Trigonella foenum-graecum) and Chinese Pak Choy (Brassica chinensis). Two experiments were conducted with the objective to increase the uptake and accumulation of tissue zinc content through various zinc source nutrient solution formulation. A modified Hoagland nutrient solution containing 300, 150, 75, 15, and 1.5 µM concentration of zinc was supplied to the plants. Both ZnSO4 and ZnCl2 were used as a zinc source. In experiment one, fenugreek plants grown in coir substrate were supplied with ZnSO4 and ZnCl2. Experiment two consisted of fenugreek seedlings grown in a growth chamber with similar Zn concentration made from ZnSO4. Zinc source had no significant effect on plant growth and shoot fresh and dry weights in experiment one. There were also no visual signs of toxicity/deficiency across various Zn concentrations in both the treatments. However, as the supplied Zn concentration decreased, the rhizosphere pH increased and the EC declined. With increasing concentration of zinc supply to root zone, tissue Zn content increased while the tissue Cu and Mn declined.