Aneurinibacillus aneurinilyticus strain CKMV1 was isolated from rhizosphere of Valeriana jatamansi and possessed multiple plant growth promoting traits like production of phosphate solubilization (260mg/L), nitrogen fixation (202.91nmolethylenemL-1h-1), indole-3-acetic acid (IAA) (8.1μg/mL), siderophores (61.60%), HCN (hydrogen cyanide) production and antifungal activity. We investigated the ability of isolate CKMV1 to solubilize insoluble P via mechanism of organic acid production. High-performance liquid chromatography (HPLC) study showed that isolate CKMV1 produced mainly gluconic (1.34%) and oxalic acids. However, genetic evidences for nitrogen fixation and phosphate solubilization by organic acid production have been reported first time for A. aneurinilyticus strain CKMV1. A unique combination of glucose dehydrogenase (gdh) gene and pyrroloquinoline quinone synthase (pqq) gene, a cofactor of gdh involved in phosphate solubilization has been elucidated. Nitrogenase (nif H) gene for nitrogen fixation was reported from A. aneurinilyticus. It was notable that isolate CKMV1 exhibited highest antifungal against Sclerotium rolfsii (93.58%) followed by Fusarium oxysporum (64.3%), Dematophora necatrix (52.71%), Rhizoctonia solani (91.58%), Alternaria sp. (71.08%) and Phytophthora sp. (71.37%). Remarkable increase was observed in seed germination (27.07%), shoot length (42.33%), root length (52.6%), shoot dry weight (62.01%) and root dry weight (45.7%) along with NPK (0.74, 0.36, 1.82%) content of tomato under net house condition. Isolate CKMV1 possessed traits related to plant growth promotion, therefore, could be a potential candidate for the development of biofertiliser or biocontrol agent and this is the first study to include the Aneurinibacillus as PGPR.

Among the organophosphate pesticides, the wide and indiscriminate use of profenofos (PFF) in agricultural and horticultural crops has resulted in serious environmental and animal health concerns and therefore demands an urgent need to develop a biological solution for its effective removal from the environment. For the bioremediation of PFF, a strain PF1, capable of utilizing profenofos as the sole source of carbon and energy was isolated from the soil samples of apple orchards of Shimla region of Himachal Pradesh, India. Based on the biochemical, FAME, and 16S rRNA gene analysis the bacterium PF1 was identified as Bacillus altitudinis (GenBank: MH986176). The strain was able to degrade 50μg mL⁻¹ PFF up to 93% within 30 days of incubation at 28°C, pH 7.0. A linear regression analysis performed on the data-set revealed the statistical significance of the relationship between the growth of the bacterial population and the degradation of pesticides. The compound 4-Bromo-2-chlorophenol (BCP) was detected as one of the pathway metabolites which further were completely degraded to lower pathway metabolites. A probable PFF degradation pathway has been proposed which follows the path from PFF to BCP and ultimately enters into the TCA cycle. To the best of our knowledge, this is the first report of PFF biodegradation by any Bacillus species of western Himalayan origin exhibiting close phylogenetic association with Bacillus altitudinis. This indigenous bacterium can be useful to bio-remediate the PFF contaminated soil as this pesticide is extensively used in the different horticulture fields in Himachal Pradesh, India. GRAPHICAL ABSTRACT