Plant Growth-Promoting Rhizobacteria (PGPR) as Biocontrol Agents for Viral Protection

Abstract

Sustainable agriculture, especially environmental sustainability, can be achieved without the use of chemical fertilizers that spoil fertility of the soil and biological diversity. There is a need for alternative measures to cope up with these problems using natural agents. The role of rhizosphere microbiology has great importance in sustainable agriculture as well as the world economy. Plant growth-promoting rhizobacteria (PGPR) is an alternative method to compete with stresses affecting the growth and development of a plant. PGPR-plant interaction is commercially used in sustainable agriculture, and their applications are studied in many horticultural and agronomic crops. There are different management strategies to control plant virus disease that include an amalgamation of selected cultural practices, using genetically resistant varieties, reducing insects’ vectors by applying the insecticidal spray, and a combination of all these. The most environmentally sound and economical option to minimize viral diseases is by far the use of genetically resistant varieties though not always available. The effective and economic measure to manage viral diseases is systemic acquired resistance (SAR), a kind of plant natural defense mechanism. Biological and chemical agents are used against viral infections. The use of PGPR and biocontrol agents (BCAs) is well-thought-out to be the most effective method to safeguard plants against plant pathogens. Many PGPRs and BCA are extensively studied against different plant pathogens and showed promising results to promote plant growth particularly against different viral diseases in various crops. There is an increasing demand of microorganism’s mixture against plant viruses in recent times where PGPR strains (individually or in combination) against numerous phytopathogens for biological control.