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Abstract Soil salinity is a major environmental stressor impacting global food production. Staple crops like wheat experience significant yield losses in saline environments. Bioprospecting for beneficial microbes associated with stress-resistant plants offers a promising strategy for sustainable agriculture. We isolated two novel endophytic bacteria, Bacillus cereus (ADJ1) and Priestia aryabhattai (ADJ6), from Agave desmettiana Jacobi. Both strains displayed potent plant growth-promoting (PGP) traits, such as producing high amounts of indole-3-acetic acid (9.46, 10.00 µgml−1), ammonia (64.67, 108.97 µmol ml−1), zinc solubilization (Index of 3.33, 4.22, respectively), ACC deaminase production and biofilm formation. ADJ6 additionally showed inorganic phosphate solubilization (PSI of 2.77), atmospheric nitrogen fixation, and hydrogen cyanide production. Wheat seeds primed with these endophytes exhibited enhanced germination, improved growth profiles, and significantly increased yields in field trials. Notably, both ADJ1 and ADJ6 tolerated high salinity (up to 1.03 M) and significantly improved wheat germination and seedling growth under saline stress, acting both independently and synergistically. This study reveals promising stress-tolerance traits within endophytic bacteria from A. desmettiana. Exploiting such under-explored plant microbiomes offers a sustainable approach to developing salt-tolerant crops, mitigating the impact of climate change-induced salinization on global food security.

Euphorbiaceae is a highly diverse family of plants ranging from trees to ground-dwelling minute plants. Many of these have multi-faceted attributes like ornamental, medicinal, industrial, and food-relevant values. In addition, they have been regarded as keystone resources for investigating plant-specific resilience mechanisms that grant them the dexterity to withstand harsh climates. In the present study, we isolated two co-culturable bacterial endophytes, EP1-AS and EP1-BM, from the stem internodal segments of the prostate spurge, Euphorbia prostrata, a plant member of the succulent family Euphorbiaceae. We characterized them using morphological, biochemical, and molecular techniques which revealed them as novel strains of Enterobacteriaceae, Lelliotia amnigena. Both the isolates significantly were qualified during the assaying of their plant growth promotion potentials. BM formed fast-growing swarms while AS showed growth as rounded colonies over nutrient agar. We validated the PGP effects of AS and BM isolates through in vitro and ex vitro seed-priming treatments with wheat and tomato, both of which resulted in significantly enhanced seed germination and morphometric and physiological plant growth profiles. In extended field trials, both AS and BM could remarkably also exhibit productive yields in wheat grain and tomato fruit harvests. This is probably the first-ever study in the context of PGPB endophytes in Euphorbia prostrata. We discuss our results in the context of promising agribiotechnology translations of the endophyte community associated with the otherwise neglected ground-dwelling spurges of Euphorbiaceae.

The commercial processing of various biomaterials extensively uses azo dyes (including reactive, direct, acidic, and basic dyes). These industrial applications produce wastewater containing a large volume of solubilized azo dye and hydrolyzed by-products. The treatment of such wastewater is primarily carried out by chemical and, to an extent, physical methods, which lack selectivity and efficiency. Notably, the chemical methods employ free radicals and oxidizing agents that further increase the chemical waste and produce non-biodegradable side-products. Therefore, there is an increasing trend of using microbial-assisted methods. The current study identified a specific Agrobacterium strain (JAS1) that degraded the three structurally distinct azo dyes (Reactive Black 5, Methyl Orange, Congo Red). JAS1 can tolerate high concentrations and be used to perform the in-solution degradation of azo dyes, respectively: Methyl Orange (5.5 g/L and 5.0 g/L), Congo Red (0.50 g/L and 0.40 g/L), and Reactive Black 5 (0.45 g/L and 0.40 g/L). Our study elucidated the molecular mechanisms (primarily enzymatic degradation and adsorption) responsible for the JAS-1-assisted decoloration of azo dyes. The JAS-1-assisted degraded products from these azo dyes were found biodegradable as the germination and seedling growth of wheat seeds were observed. To enhance the scope of the study, JAS1-assisted decolorization was studied for cellulosic materials, indicating a potential application in de-inking and de-dyeing process in recycling industries.