Enhancing In Vitro Shoot Development of Patrones-ARDA® Rootstock Through Nitric Oxide, Antioxidants, and Adsorbents

In fruit cultivation, the use of rootstocks plays a critical role in terms of plant performance, stress tolerance, and yield. Changing environmental conditions necessitate the development of new and excellent rootstocks and their rapid, homogeneous, and healthy propagation. In this context, in vitro micropropagation techniques stand out as an effective method in modern rootstock production. This study aimed to determine the effects of nitric oxide donor, antioxidants, and adsorbent substances on in vitro shoot regeneration and growth of Patrones-ARDA® rootstock. Node explants were cultured in Murashige and Skoog (MS) medium containing varying concentrations of sodium nitroprusside (SNP), ascorbic acid (AsA), silver nitrate (AgNO₃), polyvinylpyrrolidone (PVP), and activated carbon (AC). After four weeks, morphological parameters such as shooting rate, number of leaves, number of nodes, shoot length, and leaf area were evaluated. Statistically significant differences were determined between the treatments. The highest shooting rate (83.33%) was obtained with 8 mg/L AgNO₃ and 50 mg/L PVP treatments, while the 200 mg/L activated carbon treatment significantly increased growth parameters such as plant height (2.77 cm) and leaf area (1.79 cm²). SNP and AsA applications increased shoot formation at specific concentrations, but their effects on growth parameters varied depending on the concentration. Heat map and hierarchical clustering analyses revealed that regeneration and growth processes are controlled by different mechanisms; AgNO₃ was more strongly associated with shoot formation, while activated carbon and PVP were more strongly associated with vegetative growth. In conclusion, it has been determined that optimizing the types and concentrations of substances is critical in in vitro micropropagation, and that the appropriate use of these substances can significantly improve regeneration efficiency and plant quality in rootstocks.