Synergistic Interactions Between Salt-tolerant Rhizobia and Arbuscular Mycorrhizal Fungi on Salinity Tolerance of Sesbania cannabina Plants

Abstract

Legumes can host rhizobia and mycorrhizal fungi, and this triple symbiosis might be exploited to improve saline soil fertility. Therefore, a greater understanding of the interaction of rhizobia and arbuscular mycorrhizal fungus during legume growth in saline soil is required. We investigated the efficiency of salt tolerance conferred by rhizobia in mycorrhizal Sesbania cannabina. Greenhouse experiments were conducted in which S. cannabina plants inoculated with Glomus mosseae BGC NM03D (GM), and two rhizobia strains Agrobacterium pusense YIC4105 (4105) and Neorhizobium huautlense YIC4083 (4083), were exposed to 100 and 200 mM NaCl. Under 200 mM NaCl stress, plants inoculated with 4105, rather than 4083, showed significant increases in shoot and root dry mass compared with non-inoculated plants. Simultaneously, a significant increase over GM-inoculated plants in mycorrhizal colonization and dependency was recorded for 4105 ? GM-inoculated plants compared with 4083 ? GM-inoculated plants. In addition, under NaCl stress, significant increases in the number and mass of nodules, nitrogenase activity, and leghemoglobin content of nodules occurred in 4105 ? GM-inoculated plants compared with 4083 ? GM-inoculated plants. Furthermore, the activities of antioxidant enzymes in rhizobiainoculated plants were significantly higher in the GM ? 4105 group than the 4083 ? GM group. The malondialdehyde content of plants from the 4105 ? GM group was significantly lower than in the 4083 ? GM group. Thus, the results revealed a synergistic relationship among the 4105 and GM in alleviating salt stress in S. cannabina. Salt-tolerant rhizobia might improve the salinity tolerance of S. cannabina by enhancing the antioxidant system.

Effect of Salinity Stress and Microbial Inoculations on Glomalin Production and Plant Growth Parameters of Snap Bean (Phaseolus vulgaris)

“…Arbuscular mycorrhizal fungi also have the capability to improve plant nutrient uptakes by spreading their hyphae in the soil beyond rhizosphere [43]. In several studies, AMF and Rhizobium inoculations have been shown to increase nutrient uptake, water availability, and biological nitrogen fixation and thereby improve crop growth and overall relief from salt stress [11,52,53].…”

Short Communication: Growth response and dependency of endangered nedun tree species (Pericopsis mooniana) affected by indigenous Arbuscular Mycorrhizal Fungi inoculation

“…The results were in accordance with several previous studies on legumes, Sesbania aegyptiaca and Sesbania grandiflora , Cassia siamea (Giri et al 2005), Pisum sativum cv. avola (Geneva et al 2006), Albizia saponaria (Tuheteru et al 2011a,b), P. mooniana (Husna et al , 2016, Sesbania cannabina (Ren et al 2016), and Cicer arietinum L. (Garg and Singla 2016). The existence of AMF may supply P for the formation of nodules as well as increase the activity of N 2 fixation by Rhizobium (Geneva et al 2006).…”

Arbuscular Mycorrhizal Fungus Improves Rhizobium–Glycyrrhiza Seedling Symbiosis under Drought Stress

“…Several common signals and processes were involved in the establishment of these two symbiotic associations [13]. An increase in P content by mycorrhizal symbiosis could increase nitrogenase enzyme activity, leading to a higher N 2 fixation of rhizobial symbiont and in return a better mycorrhizal development [43]. In our study, rhizobia infection rate in plants co-inoculated with R. irregularis was much higher compared with single inoculated plants under drought stress conditions, which indicated that AM colonization stimulated nodule formation under stress conditions [44].…”