Rooting Systems of Soybeans. I. Differences in Root Morphology among Varieties¹

Abstract

Abstract Field experiments were conducted to delineate morphological differences among root systems of 26 soybean varieties ( Glycine max (L) Merr.). ‘Aoda’ and ‘Harosoy 63,’ were selected from the 26 varieties and strains as representative of extremes in rooting patterns. A core sampling technique was used to quantitatively analyze the rooting systems in single‐plant plots. Harosoy 63 had a more extensive root system, including a nearly twofold greater root surface area, than Aoda. The rooting morphology in single‐plant and row plots was studied qualitatively by a soil monolith method. Both varieties lacked a distinctive taproot development below a zone of profuse branching. The disposition of primary branches in the soil was apparently influenced by intraspecific competition.