Study of in vitro propagation and acclimatisation in Polianthes tuberosa cv. Pink Sapphire

Polianthes tuberosa cv. Pink Sapphire is one of the beautiful commercial flower varieties newly imported into Vietnam. However, detailed studies on the micropropagation and acclimatisation of this flower species to the local environment are lacking. To meet the production and commercial demand of this flower variety in Vietnams’ An Giang province, the study was conducted to select optimal media for in vitro propagation and suitable environments for seedling acclimatisation under greenhouse conditions. Five experiments were encompassed in this study, consisting of sterilisation of initial explants, in vitro shoot regeneration from bulb scales, in vitro shoot multiplication, complete plantlet generation and acclimatisation of seedlings in the greenhouse. The results demonstrated that the most effective sterilisation method was using 0.2 % HgCl2 for 15 min and then 10 % Ca(OCl)2 for 10 min. Four-scaling bulbs cultured on MS media containing 2.5 mg/L BAP and 0.5 mg/L NAA were recommended for in vitro shoot regeneration. The best medium for in vitro shoot multiplication was MS medium supplemented with 2 mg/L BAP and 0.5 mg/L NAA. The suitable medium for complete plantlet regeneration was MS medium. To acclimatise Pink Sapphire in the greenhouse, the optimal substrate was a mixture of rice husk ash, coconut coir and sand in equal parts (1:1:1). The findings of this study provide a foundation for the rapid development of the P. tuberosa cv. Pink Sapphire variety in An Giang province of Vietnam.