Acclimatization of tissue cultured plantlets: from laboratory to land

The ultimate success of micropropagation on a commercial scale depends on the ability to transfer plants out of culture on a large scale, at low cost and with high survival rates. During field transfer the in vitro grown plantlets are unable to compete with soil microbes and to cope with the environmental conditions. The in vitro culture conditions result in the plantlets with altered morphology, anatomy and physiology. In order to increase growth and reduce mortality in plantlets at the acclimatisation stage, efforts are focused on the control of both physical and chemical environment and biohardening of micropropagated plantlets. This review describes the abiotic and biotic stresses and current developing methods for the acclimatization of microshoots.