A Closed Plantlet Production System for ApplyingPhotoautotrophic Micropropagation

摘要

The plantlet production using conventional micropropagation is laborious and not suitedto economy of scale. Many studies on photoautotrophic micropropagation without any sucrose inthe nutrient medium under enriched CO2 and high photosynthetic photon flux showed a high netphotosynthetic rate, enhanced shoot and root growth which results in the shortening in vitromultiplication cycle and high ex vitro survival percentage. In order to simplify the culture procedureand reduce the production cost, the photoautotrophic micropropagation is suitable to apply toscale-up plantlet production in practical. In this study, a 20 m2 closed system including eightbookshelf-like culture shelves each layer with fluorescent lamps under contamination andenvironment control was operated to apply to plantlet production using photoautotrophicmicropropagation for production scale of 1.0 million plantlets per year. Contamination in the closedsystem was controlled with cleanness of ISO7-grade according to International Standard ofISO14644-1 by three-class filtration mainly by HEPA filters. The physical environment in theclosed system was maintained in high relative humidity within gradient of 10% and in a uniformdistribution in temperature, CO2 concentration, and photosynthetic photon flux when the quarterand half lamps were turn on. The temperature and relative humidity were distributed for a largegradient in photoperiod when the all lamps were turn on because of shortage in air changes. Thisclosed system will be suitable for conventional micropropagation with supplying lower PPF, butneeded to increase the air changes or change the ventilation by supplying airflow from bothsidewalls and air return from ceiling when it will be applying for photoautotrophic micropropagation