In vitro germination of amomum tsao-ko crevost & lemarié seeds

Abstract

Cardamom (Amomum tsao-ko Crevost & Lemarié) belongs to the genus Amomum Roxb. (Family: Zingiberaceae), is widely used as a flavoring and spicy ingredient in many traditional Vietnamese dishes; furthermore, it is also used in many traditional Vietnamese remedies to treat digestive ailments, malaria, bad breath, tooth decay, etc. Due to the presence of hard seed coat, cardamom has low seed germination potential. Therefore the aims of the present investigation were undertaken to study the effect of different sterilization agents, mechanical scarification, and various culture media on germination parameters of cardamom seeds. From there, an efficient in vitro cardamom seed germination protocol allows for a high germination rate and provides efficient production of high-quality sterile seedlings was described. Intact seeds were removed from aril and were soaked in warm water for 8 hours before sterilization; in the next step, they were disinfected in 0.1% mercuric chloride for 10 minutes and rinsed 4-5 times with sterile distilled water; then, they were scarified manually by cutting 1-1.5 mm of the seed coat at the opposite site of hilum by a sterile scalpel; lastly, they were inoculated onto MS medium diluted to 1/16 concentration at 25±2°C under a 16 h-photoperiod in cool white fluorescent light (2000-2500 lux). With this procedure, on average more than 33.33% of the seeds germinated after 90 days of culture, germination mean time (GMT) is 43.98 days, and germination rate index (GRI) is 0.1917.