Growth Response of Peanut (Arachis hypogaea L.) to Inoculation with Bradyrhizobium Conjugated with Rhizobacteria under Different Levels of Organic Fertilization on Sandy Soil

TWO FIELD experiments were conducted at the Agricultural Research Farm of the Higher Institute for Agriculture Co-Operation during 2008 and 2009 to study the response of peanut to inoculation with Bradyrhizobium either individually or in combination with PGPR (Pseudomonas fluorescens) under different levels of organic compost.
Regarding the response to inoculation with bacteria, results showed that there were significant increases in all peanut vegetative traits , due to inoculation with any tested bacterial strain. However, using the mixture strains (Bradyrhizobium + Pseudomonas fluorescens), surpassed other inoculated or uninoculated treatments .
The response of groundnut vegetative growth, to increasing the rate of organic fertilizer was significant. Using higher rate of compost 15-ton/fed (1 hectare = 2.4 feddan) showed higher values of all tested traits under the investigation in both seasons.
Spraying groundnut plants with humex significantly increased all tested traits under investigation compared with the non-sprayed plants in both seasons.
The effect of the first order interactions, i.e. compost x humex, compost x biofertilizers, biofertilizers x humex as well as the effect of the second order interaction (compost x humex x biofertilizers) on all studied traits of groundnut growth, were significant.