Role of Metallothionein and Phytochelatin in Combating Abiotic …
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be statistically significant. Level of significance was p < 0.05 (*); p < 0.01 (**); p
< 0.001 (***).
3 Results
3.1 Evaluation of Stress
3.1.1 Chlorophyll and Carotenoid Content
The increases in chlorophyll a content in 500 and 800 μM Cu-treated plants were
about 1.32 and 1.23 fold, followed by a drop in 1000 μM Cu-treated plants. The
increase in chlorophyll b content in the 500 μM Cu-treated plants was more significant than that of 800 μM Cu-treated plants (p ≤ 0.001 against p ≤ 0.01). There has
been significant increases (p ≤ 0.001) of 1.34 and 1.22 fold in the total chlorophyll
contents in 500 and 800 μM Cu-treated seedlings and an insignificant decrease in
1000 μM Cu-treated seedlings (Fig. 1).
Statistically significant increments in the carotenoid content have been observed
in 500 and 800 μM Cu-treated seedlings (p ≤ 0.01 and p ≤ 0.05); however, in
1000 μM Cu-treated plants show an even more significant decrease (p ≤ 0.001) in
carotenoid content (Fig. 2).
Fig. 1 Changes in total chlorophyll content