Application of beneficial microorganisms in agriculture to increase plant resistance to drought

Suša je eden izmed najbolj omejujočih dejavnikov kmetijske pridelave po svetu in bo z globalnim segrevanjem postajala vedno večji problem. Potrebne so številne prilagoditve in strategije, da rastlina preživi v sušnem stresu. Koristni talni mikroorganizmi, kot so na primer rizobakterije, ki spodbujajo rast rastlin (PGPR) in arbuskularne mikorizne glive (AMF), lahko z različnimi mehanizmi ublažijo učinke suše na rastline. PGPR lahko rastlini omogočijo boljši sprejem hranil, vplivajo na raven rastlinskih hormonov, kot so avksini, citokinini in etilen, inducirajo akumulacijo osmolitov in antioksidativne obrambne sisteme. S sintezo zunajceličnih polisaharidov (EPS) izboljšajo strukturo in vodno-retenzijske lastnosti tal ter na ta način v sušnih razmerah omogočajo boljše preživetje rastlin. AMF pomagajo rastlini ohraniti vodni potencial in pripomorejo k zaščiti rastline pred oksidativnim stresom. Poleg tega tudi izboljšajo sprejem vode in strukturo tal. Številne raziskave so pokazale povečano produktivnost rastlin po tretiranju s koristnimi mikroorganizmi, tako v optimalnih, kot tudi stresnih razmerah. Koristni talni mikroorganizmi imajo zato potencial pri uravnavanju fizioloških odzivov na pomanjkanje vode, saj rastlini lahko omogočijo preživetje v sušnih pogojih.Drought is one of the major constraints on agricultural productivity worldwide and is likely to increase even further with global warming. Several adaptations and mitigation strategies are required for plants to survive in drought. Beneficial soil microbes, for example plant growth promoting rhizobacteria (PGPR) and arbuscular mycorrhizal fungi (AMF), may alleviate drought stress with different mechanisms. PGPR affect the plant by improving nutrient acquisition, modulating the level of plant hormones, such as auxins, cytokinins and ethylene, inducing accumulation of osmolytes and antioxidants. With the production of extracellular polymeric substances (EPS) they may improve soil structure and water retention properties, thus enabling the plant to survive in drought conditions. AMF help maintain water potential of the plant and protect the plant from oxidative stress. Furthermore they improve water acquisition and soil structure.Various studies have documented the increased health and productivity of different plant species by the application of beneficial microbes under both normal and stressed conditions. Beneficial soil microbes therefore possess potential for modulating the physiological response to water deprivation, which may ensure plant survival under drought stress