Methods of Studying Root Systems in the Field

Abstract

Growing plants require photosynthetically active radiation (PAR), water, 15 to 20 elements (37), and the absence of lethal factors. Although most of the water and mineral elements used by plants is absorbed by roots, root systems have been studied in much less detail than plant tops. Part of this deficiency may be due to the “out of sight, out of mind” syndrome, but most of the deficiency occurs because root studies usually are much more time-consuming, more labor-intensive, and more costly than shoot studies. As one example, several related experiments were conducted during the 1979 growing season to obtain insight into the reason(s) why narrow-row soybeans ( Glycine max L. Merr. ‘Wayne’) outyield soybeans grown in conventional meter-wide rows (2, 13, 16, 17, 21, 22, 25, 34). Much more data were collected above-ground than below the soil surface, but the above-ground measurements required only about one-half as much labor as the below-ground measurements.