Effects of Arbuscular Mycorrhizal Fungi (AMF) and Bacterial Strains on Orobanche crenata Forsk, on Faba Bean

Abstract

Faba bean (Vicia faba L.) is an important grain legume crop in many countries and is severely constrained by infection by the weedy root parasite Orobanche crenata (crenate broomrape). The present work was carried out to evaluate the potential of arbuscular mycorrhiza fungi (AMF) and bacterial strains to suppress Orobanche crenata on faba bean. Orobanche infestation was influenced by the bacteria, AM fungi and the time the observation was made. Faba bean inoculated with the combination between bacterial strains (B2) {TAL 1399 plus A. brasilense}, B3 (TAL 1399 plus BMP{ Bacllius megathirium var phosphaticum }) alone or in combination with mycorrhiza fungi (AM) were completely inhibited Orobanche plant emergence. Time at which highest rate of Orobanche emergence occurred on faba bean was significantly delayed with AM fungi incorporated with each of the bacterial strains (B1, B2 and B3). The highest increment of faba bean shoot was obtained when AM fungi was incorporated with bacterial strains B3 as compared to control. Mycorrhizal (AM) fungi plus bacterial B2 root colonization were positively correlated with total dry matter of faba bean. With respect to nodule numbers results displayed that faba bean inoculated with bacterial B2 alone or in combination with AM fungi sustained the highest nodule numbers as compared to both controls. Adoption of an integrated approach encompassing AM fungi and bacteria inoculation may provide a novel, cheap and easy method to apply for O. crenata control under subsistence low-input farming systems.