Is the main reason is the reversible action of Epigenetic mechanisms that may enabling them to deal more flexibly with environmental fluctuations compared to the more stable genetic mechanism?!
Before answering this question lets go and see what is happening in CRISPR/CAS9! simply, in bacteria, every time that batteries exposed to some difficulties, they store one part of these difficulties to brace them selves from future attack!
that is the same thing in plant but have a different mechanism!
plant memories any stresses and make it as an Epigenetic phenomena to prepare itself for future stresses.
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