Details

Autor(en) / Beteiligte

• LIM, GLORIA

Titel

Studies on the Physiology of Nodule Formation: VIII. The Influence of the Size of the Rhizosphere Population of Nodule Bacteria on Root Hair Infection in Clover

Ist Teil von

• Annals of botany, 1963-01, Vol.27 (105), p.55-67

Ort / Verlag

Oxford University Press

Erscheinungsjahr

1963

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• With an adequate inoculum the number of infected root hairs in three species of clover (Trifolium parviflorum, T. patens and T. glomeratum) increased ex ponentially with time in two phases; the increase was rapid during the first 8-10 days before nodulation begins, but slower afterwards. T. parviflorum had most infections and T. glomeratum the fewest. Experiments on varying inoculum size, using an avirulent mutant strain of Rhizobium trifolii as diluent, showed that root-hair infection was differentially limited by inoculum size during the two phases. Infection in all three species was about doubled by doubling the density of the virulent bacteria in the rhizosphere before nodulation begins. After nodulation bacterial density had to be increased much more than twice to double the number of infections. This increase in the infecting population was inversely related to the numbers of infections formed on the three host species. Early infection and nodulation were promoted by high bacterial density in the rhizosphere.