Hierarchical clustering of pineapple MD2 stress responses in bioreactors

Gómez D.; Quintana-Zaez J.C.; Chico-Ruíz J.; Hernández–Fernández L.; Acosta Y.; Lorenzo J.C. · In Vitro Cellular and Developmental Biology - Plant (2026) · DOI: 10.1007/s11627-026-10703-z

Resumen

Pineapple (Ananas comosus L. Merr., cultivar MD2) is a key tropical crop but highly sensitive to salinity and drought, making temporary immersion bioreactors (TIBs) valuable for micropropagation and stress studies. Apical buds were cultured in vitro, transferred to TIBs with paclobutrazol, and subjected to nine treatments (control, NaCl, mannitol at 50.0 to 200.0 mM) for 30 d. Growth and biochemical traits were measured, data normalized (0 to 1), and analyzed by hierarchical cluster analysis (HCA) using average linkage and squared Euclidean distance. The dendrogram revealed clear treatment similarities: controls remained distinct until higher rescaled distances, low concentrations clustered together, and high concentrations formed separate groups, confirming dose-dependent responses. NaCl and mannitol did not cluster together initially, indicating distinct physiological profiles, with NaCl imposing additional ionic toxicity beyond osmotic effects. These findings complement earlier evaluations showing significant reductions in shoot multiplication and biomass above 50.0 mM, with critical concentrations for 50% growth reduction at 37.4 mM NaCl and 66.5 mM mannitol. Biochemical markers such as phenolics, chlorophyll b, and aldehydes were confirmed as sensitive indicators. Together, clustering and quantitative data highlight dose-dependent intensification and stress-specific differences, strengthening the rationale for biomarker-based screening and tolerance selection in pineapple biotechnology. © The Society for In Vitro Biology 2026.

Instituciones: Universidad Nacional de Trujillo