Biotechnology Journal International

Aims: The present study aimed to investigate the in vitro induction of polyploidy in Glycine max (L.) Merr. (soybean) using colchicine, and to evaluate the subsequent effects on various morphological, physiological, and cytological characteristics, ultimately assessing its potential for crop improvement.

Study Design: Germinating soybean seeds were treated in vitro with varying concentrations of colchicine (0.03, 0.05, 0.08, 0.1%) for different durations (24 and 48 hours). Polyploidy induction was identified via applying different analyses including; morphological measurements, stomatal parameters, epidermal cell count, pollen grain size, chromosomal changes during metaphase and anaphase and genomic DNA optical density. The plant improvement was assessed by measuring the concentration of photosynthetic pigment, protein content, potassium and sodium ions ratio.

Results: Treatment with 0.05% or 0.1% colchicine for 48 hours effectively induced polyploidy in soybean. Polyploid plants exhibited several desirable phenotypic changes, including darker and thicker leaves, increased plant height, and larger seeds with greater weights. Significant alterations were observed in stomata number, width, length, and index, as well as in epidermal cell count, although trichome numbers were unaffected. Cytological examination revealed increased cell size during metaphase and anaphase, larger pollen grains, higher genomic DNA optical density, and elevated concentrations of chlorophyll a, b, and carotenoids, along with increased protein content compared to diploid controls.

Conclusion: Colchicine treatment can successfully induce polyploidy in Glycine max, leading to distinct morphological, physiological, and cytological alterations. The observed improvements in seed size, photosynthetic pigments, and protein content suggest that induced polyploidy holds significant promise for enhancing soybean characteristics.