Effects of Mycorrhizal Inoculation and Phosphorus Application on the Nodulation, Mycorrhizal Infection and Yield Components of Faba Bean Grown Under Two Different Watering Regimes

Abstract

A field experiment was conducted in the 1994/95 and 1995/96 growing seasons to investigate the effects of mycorrhizal ino culation and phosphorus application on infection, symbiotic activity and yield of faba bean ( Vicia faba L.) grown under two watering regimes. Water stress significantly decreased nodule number, flower set, pod production and seed yield in both seasons. Sub stantial mycorrhizal infection occurred with low P concentration under both well - watered and dry soil conditions. However, at high soil P, mycorrhizal infection was not suppressed in the dry watering regime as it was in the well - watered treatment. Mycorrhi zal inoculation significantly increased nodule number, nodule dry weight, flower set, pod production and seed yield compared to non - mycorrhizal plants under both watering regimes, but P application alone had no significant effect on all the above mentioned parameters. The stimulation of faba bean symbiotic activity and seed yield by mycorrhizal inoculation was suppressed by the application of phosphorus.