IS THE IN VITRO ESTABLISHMENT A CRITICAL POINT IN THE EPIGENETIC STABILITY OF THE CRYOPRESERVED HOPS (HUMULUS LUPULUS L.)

In vitro establishment and micropropagation are basic techniques used as initial step in many of the plant tissue protocols such as cryopreservation. Severe physiological alterations such as changes in leaf structure, water relations and photosynthesis systems are usually associated with the in vitro establishment. In this report, the epigenetic alterations in hops caused by in vitro establishment and micropropagation are assessed using MSAP (methylation-sensitive amplified polymorphism). A 56.3% of the detected loci were monomorphic when the in vitro plants were compared to their donor field plant. Nearly 28.7% of the total loci presented the same alterations of the band profile in all analyzed in vitro plants when compared to the field donor plant. However, when the comparison was performed only among in the micropropagated plants 80.7% of the loci were monomorphic.