Native arbuscular mycorrhizal fungi isolated from a saline habitat improved maize antioxidant systems and plant tolerance to salinity.
High soil salinity is a serious problem for crop production because most of the cultivated plants are salt sensitive, which is also the case for the globally important crop plant maize. Salinity stress leads to secondary oxidative stress in plants and a correlation between antioxidant capacity and salt tolerance has been demonstrated in several plant species. The plant antioxidant capacity may be enhanced by arbuscular mycorrhizal fungi (AMF) and it has been proposed that AM symbiosis is more effective with native than with collection AMF species. Thus, we investigated whether native AMF isolated from a dry and saline environment can help maize plants to overcome salt stress better than AMF from a culture collection and whether protection against oxidative stress is involved in such an effect. Maize plants inoculated with three native AMF showed higher efficiency of photosystem II and stomatal conductance, which surely decreased photorespiration and ROS production. Indeed, the accumulation of hydrogen peroxide, the oxidative damage to lipids and the membrane electrolyte leakage in these AM plants were significantly lower than in non-mycorrhizal plants or in plants inoculated with the collection AMF. The activation of antioxidant enzymes such as superoxide dismutase or catalase also accounted for these effects.
Departamento de Microbiología del Suelo y Sistemas Simbióticos. Estación Experimental del Zaidín (CSIC). Profesor Albareda n° 1, 18008 Granada, Spain.
Beatriz
B
Estrada
Ricardo
R
Aroca
José Miguel
JM
Barea
Juan Manuel
JM
Ruiz-Lozano
D000975:Antioxidants / Q000378:metabolism*; D002374:Catalase / Q000378:metabolism; D017753:Ecosystem; D004789:Enzyme Activation; D006861:Hydrogen Peroxide / Q000378:metabolism; D015227:Lipid Peroxidation; D038821:Mycorrhizae / Q000254:growth & development* / Q000378:metabolism; D018384:Oxidative Stress; D010788:Photosynthesis; D045332:Photosystem II Protein Complex / Q000378:metabolism; D010940:Plant Proteins / Q000378:metabolism; D018517:Plant Roots / Q000378:metabolism / Q000382:microbiology*; D018520:Plant Shoots / Q000378:metabolism; D054046:Plant Stomata / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D054712:Salinity; D055051:Salt-Tolerant Plants / Q000201:enzymology / Q000378:metabolism / Q000382:microbiology*; D013482:Superoxide Dismutase / Q000378:metabolism; D013559:Symbiosis; D003313:Zea mays / Q000201:enzymology / Q000378:metabolism* / Q000382:microbiology
D000975:Antioxidants; D045332:Photosystem II Protein Complex; D010940:Plant Proteins; D017382:Reactive Oxygen Species; D006861:Hydrogen Peroxide; D002374:Catalase; D013482:Superoxide Dismutase