Author/Authors :
Salehi Eskandari، Shahrzad نويسنده MD. Plant Biology, Mehregan University, Mahallat, Iran. ,
Abstract :
This research was done in hydroponic environment in greenhouse at 3
stages (vegetative, flowering and full product) in 5 concentrations of Cd (0.1,
0.3, 0.9, 2.7, and 10 ?m) for investigating physiological and biological
effects. This study revealed that the increase of Cd concentration in understudy
treatments causes the 49% reduction of sugar solution in 10 ?m treatment. On
the other hand, the gradual increase of Cd in cultivation caused the increase
of starch, reduction of photosynthesis and blockage of carbon cycle enzymes.
Furthermore, in heavy metal stress conditions of vegetative stage, Cd has
negative effects on the protein amount of total treatments in p=0.01 signified
level. When treatment starts, the amount of protein reduced until 33% in 0.1
?m concentration and this reduction can be seen also in other treatments. In
contrast, in flowering stage the amount of protein is increased compared to
the control. The study of different heavy metal concentration effects showed
that plants are more sensitive to Cd (2-20 times more than others). The Generalized
Linear Model variance test of aerial and underground plant organs
traced the high level of Cd concentration in root in10 ?m concentration. This
increasing process in p=0.001 level also was seen in root, leaf, and fruit. The
accumulation of Cd expressed high speed of Cd transport from the soil to
upper organs of tomato, and this process reduced the amount of solvable
sugar and protein.