Abstract
Abstract The preservation of genetic resources of wild relatives of cultivated plants, such as Pyrus regelii, is crucial for maintaining biodiversity, ensuring food security, and supporting the sustainable development of ecosystems. P. regelii is an endemic, relict species that is native to Kazakhstan and a very good research plant material due to its agronomically valuable traits, such as drought tolerance and disease resistance. Therefore, this study aimed to develop an effective in vitro conservation protocol for Pyrus regelii by investigating the effects of various plant growth regulators on its in vitro multiplication, in vitro rooting, and slow-growth storage phases. An effective micropropagation protocol was developed using the plant growth regulators meta-topolin (1.0 mgL−1) and gibberellic acid (0.2 mgL−1), where 29.47 microshoots per explant were obtained. For in vitro rooting, the most effective medium was ½ WPM, with an average of 3.1 roots formed per explant and rooting percentage of 77%. A slow-growth storage technique at + 4 °C was also developed, in which the combination of abscisic acid (1.0 mgL−1) and mannitol (2%) in ½ WPM medium effectively suppressed microshoot growth while maintaining plant viability for 4 month without re-cultivation. The results suggest that micropropagation and slow-growth storage at + 4 °C can be used to conserve the endemic, relict P. regelii.