A Summary of Porous Tube Plant Nutrient Delivery System Investigations From 1985 to 1991.

AbstractThe Controlled Ecological Life Support System (CELSS) Programis a research effort to evaluate biological processes at a oneperson scale to provide air, water, and food for humans in closedenvironments for space habitation. This program focuses currentlyon the use of conventional crop plants and the use of hydroponicsystems to grow them. Because conventional hydroponic systems aredependent on gravity to conduct solution flow, they cannot be usedin the microgravity of space. Thus, there is a need for a systemthat will deliver water and nutrients to plant roots undermicrogravity conditions. The Plant Space Biology Program isinterested in investigating the effect that the space environmenthas on the growth and development of plants. Thus, there is also aneed to have a standard nutrient delivery method for growing plantsin space for research into plant responses to microgravity. ThePorous Tube Plant Nutrient Delivery System or PTPNDS utilizes ahydrophilic, microporous material to control water and nutrientdelivery to plant roots. It has been designed and analyzed tosupport plant growth independent of gravity and plans areprogressing to test it in microgravity. It has been usedsuccessfully to grow food crops to maturity in an earth-boundlaboratory. This document includes a bibliography and summaryreports from the growth trials performed at KSC utilizing thePTPNDS.iii