Quantitative assessment of the bacterial rhizosphere flora of Pinus contorta var. latifolia

Abstract

The bacterial flora associated with root systems of young and mature lodgepole pine was investigated by sampling forest-grown trees. Counts were performed and expressed on a surface-area basis to give a more realistic comparison of organism density or activity within the control soil, rhizosphere soil, and rhizoplane. On this basis, densities increased by an order of 10(4)- to 10(6)-fold from control soil to rhizoplane, with the degree of stimulation being inversely related to root radius.