**4.5 Oxidative stress**

With decrease in photosynthesis formation, reactive oxygen species increases and increasing of reactive oxygen species increases production of enzymes that enable detoxify of these reactive oxygen species. While plants adapt to changing environment, they undergo the activation of biochemical processes that prevent oxidative damages against photosystem, leaf morphology, chloroplast pigment composition and many other changes. Reactive oxygen species can divide the activities of plant. For example, DNA, proteins and lipids make negative effects by mixing into plant metabolism [29].
