ABSTRACT
Unlike airborne plant organs, plant roots are “hidden” in the ground and can be reached in their natural environment only by using special procedures or equipment. Unfortunately, environmental conditions vary with respect to space and time. Experimental layouts and treatments in field research are often masked by unforeseen changes in the environmental conditions. Therefore long-term observations and large numbers of replications are required for meaningful root research in the field. The processes and reactions of root growth can be studied under controlled conditions in laboratories, and by that the cost-intensive investments in such fieldwork can be avoided. However, growth conditions in laboratories can seldom represent natural environments. A compromise between field and laboratory research may be achieved by using so-called growth laboratories. These started out as simple underground glass windows and have since developed into high-technology rhizolaboratories.
