Morphological, biochemical, and molecular assessment of the effect of carbohydrate sources in Lycium barbarum micropropagation

Efficient micropropagation of goji requires culture conditions that support plant regeneration while maintaining high physiological quality. This study evaluated the effects of sucrose, fructose, glucose and maltose, applied at 15 and 30 g L− 1, on nodal explants of Lycium barbarum L. These concentrations corresponded to 43.8 and 87.6 mM for sucrose and maltose, and to 83.3 and 166.5 mM for fructose and glucose, respectively. Sugar free MS medium was included as an experimental variant. After six weeks, shoot number, shoot length, root length, dry mass content, photosynthetic pigment concentration, total polyphenol content and RAPD marker profiles were assessed. Sucrose was the most effective carbohydrate for shoot multiplication, producing the highest number of shoots per explant. Maltose promoted greater shoot and root elongation and maintained high chlorophyll and carotenoid contents. In contrast, glucose and fructose, particularly at 30 g L− 1, were associated with higher dry mass percentage and total polyphenol content, but also with reduced organ elongation and lower pigment contents. This response pattern was consistent with a less balanced, stress-like physiological response, possibly related to the higher molar concentrations and osmotic load of monosaccharide treatments. Exploratory RAPD analysis revealed differences among pooled treatment-associated marker profiles. Because DNA was pooled for each treatment and donor material was not included, molecular marker-profile responses, clonal fidelity, mutation frequency and somaclonal variation could not be assessed. Overall, carbohydrate type and concentration affected the morphogenetic, biochemical and pooled RAPD - profile responses of L. barbarum cultures. Sucrose was most favorable for shoot multiplication, whereas maltose supported a more balanced elongation and physiological response. Carbohydrate source and concentration shaped in vitro Lycium barbarum responses: sucrose promoted shoot multiplication, maltose supported balanced elongation and pigments, while exploratory RAPD revealed differences among pooled treatment-associated marker profiles.