Carbohydrate status and post storage recovery of micropropagated hosta plantlets stored at varying temperatures in light or darkness.

摘要

Hosta (Hosta tokudama 'Newberry Gold') plantlets were micropropagated photoautotrophically (without sugar in media) or photomixotrophically (with sugar in media) for 3 weeks at 23鳦 and 80 鎚ol.m-2.s-1 photosynthetic photon flux (PPF) prior to longterm storage. Light compensation points were determined prior to each long-term storage experiment so that plants could be stored without excessive growth. Plantlets were stored for 4, 8, or 12 weeks in darkness or under white light (400-800 nm) and thentransferred to the greenhouse for 60 days. Three independent experiments were performed at 5-, 10-, or 22鳦. Illumination during storage was necessary to maintain total soluble sugars (TSS), starch, and regrowth potentials of in vitro plantlets. All photoautotrophic plantlets stored in darkness were of poor quality and died when transferred to the greenhouse. Dark-stored photomixotrophic plantlets survived storage for 12 weeks at 5 鳦 but declined in appearance when storage temperature increased to 10and 22鳦. The visual quality and greenhouse acclimatization of illuminated plants was best when plants were stored at 22鳦. After 60 days in the greenhouse, the dry weight of these plantlets was similar for 0, 4, 8, and 12 week storage periods. Supplying2% sucrose in the culture medium increased leaf TSS and maintained overall plantlet quality during illuminated storage.