Abstract
Vegetables are irrigated with wastewater from industries in some parts of Pakistan. The wastewater from municipal and
industries contains a variety of contaminants including metals. The aim of present study was to assess the effects of cadmium
(Cd) stress from irrigation wastewater on spinach, its uptake by plant and subsequently development of a strategy to mitigate
the stress. For this purpose, spinach was grown in pots irrigated with Cd contaminated wastewater and impacts were assessed
using different physicochemical parameters. Two different organic amendments namely cow dung and wood charcoal at 20
and 30 t ha-1 were used to check the kinetics of Cd in soil and plants. Results revealed that maximum fresh biomass was
recorded for treatment receiving 30 t ha-1 of charcoal (10 g per pot) followed by Cd alone treatment @ 9.5 g pot-1
. At the same
rate of cow dung, the lowest uptake of Cd by spinach plant was recorded. Maximum Cd concentration was measured at
treatment with metal alone control (0.91 mg kg-1
), while minimum of 0.016 mg kg-1 DM was at the highest level of cow dung
in herbage. In soil, lowest Cd concentration (0.10 mg kg-1
) was noticed in the cow dung treatment i.e. T5. Organic carbon
content was found highest (0.034 mg g-1
) in charcoal treatment at higher level. . The FTIR analysis of charcoal was conducted
that showed peaks at 2250, 1000 and 2000 cm-1
showing C-C, C-O-C and C=C bonding, respectively. Overall, cow dung
proved the best assimilator of Cd and the use of this bio-organic waste as a filter for wastewater treatment or soil conditioner
is an innovative and emerging idea that deserves further attention and sorption studies.
