Application of artificial seeds for in vitro propagation and storage of Codonopsis javanica Blume

Abstract

In this work, Codonopsis javanica plants derived from the Lang Biang Highland of Lamdong province were used to study artificial seeds. Artificial seeds were produced using stem nodes and shoot tips excised from in vitro-derived Codonopsis javanica plants for serving as embryos, 3% sodium alginate with 100 mM CaCl2.2H2O for creating seed coat, and MS liquid medium as endosperm. After 20 days of artificial seed sowing, the experimental results showed that MS medium supplemented with 0.5 mg/l Kinetin, 30 g/l sucrose, 8 g/l agar and pH at 5.8 was optimal for seed germination and shoot regeneration, with the germination rate at 85%, shoot number at 5.8 shoots/seed and height at 2.46 cm. For the experiment using TDZ, MS medium supplemented with 0.2 mg/l TDZ, 30 g/l sucrose, 8 g/l agar and pH at 5.8 was optimal for shoot regeneration and shoot growth, with 7.8 shoots/seed. On the same medium for artificial seed sowing, the activated charcoalfree medium stimulated the shoot regeneration and shoot growth, but the medium containing 1 g/l activated charcoal was unsuitable for shoot regeneration as well as shoot growth. The MS medium supplemented with 1 mg/l IAA was optimal for root regeneration from shoot tip-derived artificial seeds, with a rate of 96.67%. The coconut fiber peat substrate or the mixture of ½ coconut fiber peat + ½ sand was suitable for the growth of artificial seed-derived Codonopsis javanica plants under ex vitro conditions after 15 days of cultivation, with the survival rate of 100%. In addition, results also showed that stem node-derived artificial seeds when stored in the dark could survive for at least 120 days