Arbuscular-mycorrhiza-induced salt tolerance and resistance to Fusarium root rot in asparagus plants
Soil salinity affects the establishment, growth, and development of crops, causing important yield losses. On the other hand, several studies on the interactions between pathogens and salinity have indicated increased disease at higher salinities. These limitations can be overcome by the application of arbuscular mycorrhizal fungi (AMF). Mycorrhizal (Gigaspora margarita) asparagus (Asparagus officinalis L. Welcome) plants were subjected to 200 mM NaCl solution and Fusarium root rot pathogen (Fusarium oxysporum f. sp. asparagi MAFF 305556; Foa). After salt and Foa application, mycorrhizal plants showed better growth than non-mycorrhizal plants. In salt conditions, mycorrhizal plants showed reduced Na+ levels in shoots and roots compared with non-mycorrhizal plants. After Foa inoculation in mycorrhizal plants with salt stress, disease incidence and indices became lower. Therefore, better growth, lower accumulations of Na+, and a lower disease incidence and indices suggested alleviation of salt and Fusarium root rot. As for oxidative stress reduction, radical scavenging activity by enzymatic antioxidants superoxide dismutase (SOD) and non-enzymatic antioxidants 2,2-diphenyl-1-picrylhydrazyl (DPPH) also increased in mycorrhizal plants under dual stress conditions. From these findings, it was confirmed that arbuscular mycorrhiza improves salt tolerance and protects asparagus plants against Fusarium root rot. In addition, AMF symbiosis could alleviate common oxidative stress damages, resulting in the protection of asparagus against oxidation and improved growth under dual stress conditions.
Haque, S.I. and Matsubara, Y. (2018). Arbuscular-mycorrhiza-induced salt tolerance and resistance to Fusarium root rot in asparagus plants. Acta Hortic. 1227, 365-372
Gigaspora margarita, Fusarium oxysporum f. sp. asparagi, superoxide dismutase (SOD), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, symbiosis