Research On CO₂ Enrichment Method Applied In Sugar Free Plant Tissue Culture

At present, sugar free plant tissue culture has not been taken into use, mainly because of such reasons as CO₂ concentration can not be regulated precisely, no appropriable light source can be used, and there are not enough knowledge on the effect of CO₂ and light on tissue culture plantlets and on rule of plantlets contamination.On the base of current research in sugar free plant tissue culture, a kind of CO₂ enrichment system and a kind of photosynthesis measurement system were developed, effect of CO₂, light intensity, photo period and light type on the photosynthesis rate was investigated, and a kind of new lamp was selected for plant tissue culture. In the article, the layout of lamps, rule of respiration of tissue culture plantlets in darkness, rule of contamination, characteristic of production mode of plant tissue culture were investigated. At the end of the article, a scheme of sugar free plant tissue culture was brought out. The main content were as follows.(1) A kind of CO₂ enrichment system was developed. This system was consisted of hardware sub-system and software sub-system. Hardware sub-system was composed of computer, data access and control card, CO₂ enrichment controller, CO₂ concentration sensor, sugar free plant tissue culture box and gas source. CO₂ enrichment controller was designed and fixed by the author and it was composed of electrical source, pneumatic components and electronic equipment. The interface of the CO₂ enrichment controller was designed by rule of standardization and the user needn't know its composition in normal use.Software sub-system of CO₂ enrichment system was written with VC++6 language to control the hardware. This system had function of data collection, data analyse, data save and signal output. The original driver of the data access card was complicated and not well usable and the author rewrote it for easier use. As a result, the new driver was modularized written and was easily used in programming. With friendly interface the compiled program was easily manipulated and feasible to ordinary worker.Working accurately, CO₂ enrichment system had a max error not more than 100μL-L^-1 and the error was mainly from error of CO₂ sensor. Sugar free plant tissue culture with multi culture box was also investigated in the article.Beside usage in tissue culture, CO₂ enrichment system could also be used in greenhouse and other gas concentration regulating system after being altered.(2) Photosynthesis rate measurement system was developed. This system was composed of hardware and software. The main composition of hardware was the same as that of CO₂ enrichment system but with more precision and reliability and some other components were added to maintain the pressure of gas source.The software of the system has function of data save, data statistic, data analyse and data output. Calculating results can be output to interface precisely with time sequence. The interface of software was so friendly that user can easily adjust element of output to require best view and printing result.With this system photosynthesis rate of plantlets in any time can be calculated. So difference in photosynthesis can be compared in order to select more suitable environment for tissue culture plantlets. With this system situation that environment was judged only through measuring such physiological guideline as dry weight and fresh weight was improved and tissue culture experiment can be done faster and conveniently.With this system respiration of tissue culture plantlets can be investigated. Through analyzing change of CO₂ concentration in culture box in darkness, respiration rate of plantlets can be evaluated. In addition, with this system CO₂ saturation point and compensation point of plantlets can be evaluated.This system was characterized by automation, continuously measure and high precision and was more favorable in measuring photosynthesis of plant colony. After being altered, this system can be used to measure photosynthesis rate of field crops.(3) Effect of CO₂ on photosynth...