Microbial priming elicits improved plant growth promotion and nutrient uptake in pea

Abstract

Legume–microbial interactions focus mainly on Rhizobium. The present study aimed to evaluate the plant growth-promoting (PGP) potential of bacterial and cyanobacterial formulations and variety-specific differences following their inoculation in two varieties of pea (Pisum sativum L.), namely Arkel and GP-17. Providencia sp. PW5–Anabaena laxa CW1 treatment was the most promising, with an 11%–76% increase in defense enzyme activity in both varieties. Interestingly, Arkel responded better in terms of nitrogenase activity, which was enhanced several-fold in the inoculated treatments, and exhibited a significant correlation (r = 0.787, 0.778, 0.755; p < 0.05) with shoot length, fresh weight and nodule number per plant, respectively. Nodule number was significantly correlated (r = 0.74, 0.81; p < 0.05) with PAL and PPO activity, respectively, and with microbial biomass carbon, alkaline phosphatase and dehydrogenase activity (r = 0.582, 0.538, 0.666; p < 0.05), respectively. Variety GP-17, however, responded better in terms of increasing the polysaccharide and glomalin content of soil. This study reveals the promise of co-inoculation of PGPRs (plant growth-promoting Rhizobacteria) as synergistic partners for improving plant growth mobilization of major nutrients in pea. However, there is a need to study root exudate patterns to identify promising microbe–variety combinations.

Microbial Inoculants with Multifaceted Traits Suppress Rhizoctonia Populations and Promote Plant Growth in Cotton

“…also showed promise in terms of the high activity of dehydrogenase and enhancing carbon and polysaccharide content of the soil. Both glomalin and polysaccharides play significant roles in the aggregation and sequestration of organic matter (Purin and Rillig 2007), and our earlier studies in pea crop have shown similar increases in these two parameters (Verma et al 2016).…”

“…Analyses of glomalin content due to the application of cyanobacterial strains and biofilms used in this study revealed that they may contain 200-300 lg/g wet weight or 2400-3900 GRSPs/g dry weight (pers. Both glomalin and polysaccharides play significant roles in the aggregation and sequestration of organic matter (Purin and Rillig 2007), and our earlier studies in pea crop have shown similar increases in these two parameters (Verma et al 2016). Being a major component of soil organic matter (as much as 5% of soil C), glomalin is known to be reduced or inhibited when organic C is prevalent, especially under no-till conditions.…”

Boosting Alfalfa (Medicago sativa L.) Production With Rhizobacteria From Various Plants in Saudi Arabia

“…The superiority of strain JD-14 ( Acinetobacter pittii ) in this study may be due to increased phosphate solubilization and ACC deaminase activities, as our findings agree with those of Baig et al ( 2012 ), which reported better nutrient uptake for PGPR that displayed phosphate solubilization and ACC deaminase activities than for those that did not. Likewise, Ahmad et al ( 2016a ), Subhashini et al ( 2016 ), and Verma et al ( 2016 ) reported enhanced nutrient content and uptake in different crops with PGPR application.…”

Insights to plant–microbe interactions provide opportunities to improve resistance breeding against root diseases in grain legumes

“…Certain members of the microbial community play a crucial role in the expression of disease resistance of plants. Mechanisms by which beneficial microorganism protect crop plants from diseases include (a) enhancement of overall vigour (e.g., via nutrient mobilization), (b) direct antagonism via parasitism or antibiosis (feeding directly on phytopathogenic microbes or producing antifungal/antibacterial metabolites), (c) niche exclusion (e.g., competition for resources), and (d) induction of systemic and localized resistance (Conrath et al, ; Shoresh, Harman, & Mastouri, ; Sindhu, Dua, Verma, & Khandelwal, ; Verma, Adak, & Prasanna, ; Xue, ). For instance, Trichoderma belongs to one of the best‐studied genera with antagonistic activity against a wide range of root pathogens (Harman, Howell, Viterbo, Chet, & Lorito, ).…”

“…To overcome such limitations, it is necessary to consider complex plant-microbe interactions and develop screening systems that account for multiple interactions among pathogens, beneficial microbes, and the host plant genotype. (Conrath et al, 2006;Shoresh, Harman, & Mastouri, 2010;Sindhu, Dua, Verma, & Khandelwal, 2010;Verma, Adak, & Prasanna, 2016;Xue, 2003). For instance, Trichoderma belongs to one of the best-studied genera with antagonistic activity against a wide range of root pathogens (Harman, Howell, Viterbo, Chet, & Lorito, 2004).…”