Role of biofertilizer on faba bean growth, yield, and its effect on bean aphid and the associated predators

Abstract

The role of biofertilizer on parameters of faba growth, nodulation, yield and also its effects on aphid infestation and the associated predators were studied. Field experiments were conducted at the Production and Research Station of National Research Center in El-Nobaria, Egypt in the 2005/06 season. Four treatments were carried out: inoculation with rhizobia alone (R), mixed rhizobia with pseudomonas (R + P), rhizobia + mycorrhiza (R + M) or rhizobia + pseudomonas + mycorrhiza (R + P + M) compared to the fifth treatment with recommended dose of chemical fertilizers NPK (150 kg: 150 kg: 200 kg/ha). There was a significant positive effect of rhizobia strains as evident from fresh and dry weight of leaves and stems, root/shoot ratio, pods/flowers ratio as well as the number and weight of nodules compared to NPK fertilizer plots. A total count of bacteria was higher significantly in mixed inoculant's strains than in single inoculant. Either single or mixed inoculants strains showed positive response on seeds weight compared to NPK plots. The highest number of pods was achieved in treatment of rhizobia mixed with mycorrhiza or pseudomonas. Three treatments were conducted for aphid's control. The percent of aphid reduction caused by aphid-control treatments was Pirimiphos-methyl (98%), m-pede (62%), and NeeemAzal T/S (50%). The mixed inoculants strains caused a good reduction percent of aphid population (71.3%) compared to single inoculation (64%). Therefore, we recommend using the mixed inoculants strains as commercial inocula for improving production of faba bean.