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To investigate the cultivating effects of several mineral matters used as root-zone media for higher plant growth in space.Four kinds of artificial and natural mineral matters were used as plant root-zone media based on lots of investigation and analysis. Nutrient liquid was delivered into the media by a long capillary material, and roots of plants obtained nutrition and water from the media. The related parameters such as plant height and photosynthetic efficiency were measured and analyzed.The growing effect in a mixture of coarse and fine ceramic particles with equal quantity proportion was the best, that in fine ceramic particles was the second best, that in clinoptilolite particles was the third and that in diorite particles was the last.The mixture of coarse and fine ceramic particles with equal quantity possesses not only fine capillary action, but also good aerating ability, and therefore is capable of being utilized as an effective root-zone media for higher plants intended to be grown in space.

To select suitable light source for higher plant cultivation in the controlled ecological life support system of the future space station.The experiment was carried out in the Space Higher Plant Cultivation Ground-based Experimental Facility (SHPCGEF); four combinations of two red and blue light-emitting diode (LED) were utilized as light sources; soilless cultivation technique with porous ceramic tubes and porous ceramic particles was utilized in the growth system.The plants grown under the shelf of pure red LED showed a lying-down state in early stage, and stood erect in later period with slender and long stems; the plants under various combinations of red and blue LED grew with nearly normal state, but the plants under the combination of 90% red and 10% blue LED possessed the best comprehensive indexes.The normal growth and development of plantlets needs two light sources of red and blue LED, and the combination of 90% red and 10% blue LED is the optimum one among those tested combinations.