Abdelwahab, R., Leila, B., Nacera, T., Yousra, B., Fatm, N., Cruz, C. & Nabti, H. (2016) A Pseudomonas protegens with high antifungal activity protects apple fruits against botrytis cinerea gray mold.
Using beneficial bacteria to control plant pathogens has become an ecofriendly alternative to the excessive use of
chemicals. In this investigation, a bacterial strain RhiNA, isolated from an agricultural land in northern Algeria (Bejaia), was selected based on its ability to produce antifungal and plant growth promoting (PGP)-metabolites. It was then molecularly identified and screened for its antagonistic activity against B. cinerea, Mucor sp., A. niger and A. flavus. The isolate was also tested for its ability to attenuate gray mold caused by B. cinerea on apple fruits. This strain, identified as Pseudomonas protegens, produced several hydrolytic enzymes, IAA, siderophores, HCN, ammonia and showed potential inhibition of mycelial growth and spore fungal germination (PGI : 66,66,62 and 58% ; SGP : 14.32, 55.10, 28.92 and 10.15% against A. niger, Mucor sp., B. cinerea and A. flavus, respectively). Only 172.823 mm2 of each inoculated area on apple fruits were touched by B. cinerea-gray mold, compared to 529.74 mm2 of rotted zone in absence of the strain. P. protegens-RhiNA shows high efficiency against a virulent fungal strain of B. cinerea. Thus, it could be used as a biocontrol agent for a sustainable agriculture in future.