Bacillus thuringiensis beyond insect biocontrol: plant growth promotion and biosafety of polyvalent strains

The entomopathogenic bacterium Bacillus thuringiensis is widely used for the control of many agricultural insect pests and vectors of human diseases. Several studies reported also on its antibacterial and antifungal activities. However, to our knowledge there were no studies dealing with its capacity to act as a plant growth promoting bacterium. This review surveys the potential of B. thuringiensis as a polyvalent biocontrol agent, a biostimulator and biofertiliser bacterium that could promote the plant growth. Also, discussed is the safety of B. thuringiensis as a bacterium phylogenetically closely related to Bacillus cereus the opportunistic human pathogen and Bacillus anthracis, the etiological agent of anthrax.