I do not think that one can proffer a definite answer to that. Oxidative stress is a function of activities of free radicals which cause damage to cells. Thus prevailing environmental factors in the area of study would determine it. Depending on which biomarker you choose you can conduct assays on samples to determine the trend in your study area.

Thanks Nnamdi Henry.

Hello Rahat Sharif!

I Cannot give you an answer for your question. Instead, I can give you some tools to think and search it.

As was said the oxidative stress is an aspect that depends on many factors - in apple plants the mainly factors will be nutrition, water, light, temperature, carbon and so on.

If these plants are in a comfortable conditions, there will be a low percentage of oxidative stress.

If these plants are under a moderate stress (one of factor or combined ones) at start of this stress the plant will suffer high oxidative stress, but they will combat this stress, triggering some defense. But what define how strong is this stress? The studied specie, variety, life stage, how adapted the specie is, etc.

Also different methods will gives you a sort of results. To relieve it, you could employ the most used essays, to make the comparison easier, but attention because there is a risk to make mistaken associations.

In a general way it's it... 

Thanks Daniele RS, That's helpful.