Rhizobacteria and Acylated Homoserine Lactone-Based Nanobiofertilizer to Improve Growth and Pathogen Defense in Cicer arietinum and Triticum aestivum Plants

In the current study, we have developed a lightweight nanocomposite biofertilizer (NCB) consisting of a physical mixture of acylated homoserine lactone (AHL)-coated Fe-carbon nanofibers (Fe-CNFs) and bacterial (Panebacillus polymyxa) endospores immobilized in activated carbon beads. AHL/Fe-CNF is translocated to plants via apoplastic movement through roots to shoots and leaves, while the endospores are retained in soil, augmenting plant growth via siderophore and indole acetic acid production. We tested NCB on the leguminous (Cicer arietinum) and nonleguminous (Triticum aestivum) plants to corroborate its broad range applicability. The results show that plants grown for 30 days after supplementing NCB had a significant (p < 0.05) increase in biomass, root length, and chlorophyll as well as protein contents. In addition, the plants grown using NCB for 21 days developed a significant (p < 0.05) potential to resist Fusarium wilt of chickpea and root rot of wheat caused by Fusarium oxysporum f. sp. Cicero and Cochliobolus sativus, respectively. Overall, the developed material showed promising applicability in the plant growth-promoting activities and protection from common fungal disease in tested plant varieties.