Mid-infrared spectroscopy reveals biochemical changes during Pinus radiata somatic embryo maturation.

Overview & Synopsis

Reliable maturation of Pinus radiata somatic embryos is fundamental for efficient clonal propagation, as embryo quality strongly influences subsequent germination, plant development, and field performance. However, objective methods for assessing embryo maturity and predicting developmental potential remain limited. This study investigated biochemical changes occurring during somatic embryo maturation and evaluated the potential of mid-infrared (MIR) spectroscopy as a rapid, non-destructive tool for developmental characterization.Three embryogenic cell lines were monitored throughout the maturation process using biochemical analyses, dry weight determination, germination assessments, and MIR spectroscopy. A distinct developmental transition was consistently observed between weeks 6 and 8 of maturation and was accompanied by significant changes in protein, lipid, and carbohydrate composition, together with increased dry matter accumulation. These biochemical changes coincided with improvements in embryo physiological quality and germination performance. MIR-based regression models accurately predicted the measured biochemical parameters, while classification models successfully discriminated among maturation stages.The results demonstrate that MIR spectroscopy can rapidly capture biochemical changes associated with embryo development and provides a practical approach for monitoring maturation, assessing embryo quality, and supporting optimization of P. radiata somatic embryogenesis protocols.