Impact of Temperature Fluctuations and Light Intensity on Shoot Regeneration Efficiency in Plant Tissue Culture

The present study investigated the survival and shoot regeneration efficiency of banana seedlings under varying medium compositions, temperature fluctuations, and light intensities. The highest survival rate (89%) was observed with MS (Basal) medium supplemented with 3.5 mg/L BAP, 0.5 mg/L IAA, and 30 g sucrose, followed closely by SM9 and SM10 (88%). The lowest survival rate (60%) occurred with SM8, which contained 7.0 mg/L BAP. Shoot regeneration efficiency was significantly influenced by temperature, with the highest rate of 92.5% recorded at 25°C under bright light. In contrast, regeneration capacity declined sharply under suboptimal temperatures, with no shoots at 0°C, 13.4% at 10°C, and 26.3% at 15°C. At 37°C, regeneration efficiency also decreased markedly. Light intensity and quality had a profound impact on regeneration rates, with bright light promoting 97% regeneration rate compared to only 18% under dark conditions. Red light enhanced overall growth, while blue light regulated growth in specific plant parts. Oxidative stress caused by phenolic compound accumulation under unfavorable temperatures and conditions inhibited regeneration and increased mortality. Furthermore, nutrient media lacking phytohormones exhibited no regeneration capability. These findings highlight the critical importance of optimizing temperature, light intensity, and medium composition to improve the survival and propagation efficiency of banana seedlings.