The Production of Virus-free Sweet Potato Mother Plants in Malaysia through Meristem Culture

Abstract

Aims: Sweet potato is a significant root crop in Malaysia due to its nutritional and economic importance. This study represents the first report on the virus elimination technique for sweet potatoes in Malaysia, addressing the growing demand for virus-free propagation materials of sweet potato varieties, VitAto and Lembayung. The research aimed to investigate the effect of plant growth regulators on meristem culture, validate the virus presence in meristem-derived plantlets, and observe the development of planting material from virus-free mother plants. Methodology: Young shoots from sweet potato tubers were sterilised and the meristematic tissue were extracted under a stereomicroscope. These meristems were cultured on Murashige and Skoog (MS) medium supplemented with various PGRs to assess shoot and root regeneration. Virus presence was validated using PCR. Results: Results showed that MS medium with 1 mg/L BAP and 1 mg/L GA3 was optimal for Lembayung, while 0.5 mg/L BAP was ideal for VitAto. Both Lembayung and VitAto exhibited optimal regeneration in PGR-free MS media. Meristem culture achieved 97.2% virus-free Lembayung and 84.7% virus-free VitAto plantlets, with only the SPVG virus detected in 2.8% of Lembayung and 15.3% of VitAto. Acclimatised plantlets developed into virus-free mother plants, yielding 108 cuttings per Lembayung plant and 98 cuttings per VitAto plant after two months. Conclusion: This study demonstrates that the meristem culture enables the production of disease-free, genetically stable, and high-quality planting materials. The ability to rapidly propagate superior cultivars ensures a steady supply of healthy plantlets, enhancing agricultural productivity and bolstering food security in Malaysia.