Effectiveness of encapsulated plant growth-promoting bacteria, Acinetobacter sp. and organic supplements on the growth and nutrient contents enhancement in chilli plant

Aims: This study was aimed to determine the effectiveness of previously isolated plant growth-promoting bacteria (PGPR) ( Acinetobacter sp. SR R-12) and organic supplements on the growth and nutrient content of chilli plant during its vegetative growth phase. Methodology and results: The present study involved the encapsulation of a previously identified strain of Acinetobacter sp. (accession no: KB851199) using sodium alginate beads. A completely randomized design was employed, and four different treatments were administered, namely T0-encapsulated PGPR alone; T1-encapsulated PGPR + humic acid; T2-encapsulated PGPR + fish amino acid; and T3-encapsulated PGPR + humic acid + fish amino acid. After 5 days, these treatments were applied to chilli seeds that had already been sowed. The plants were harvested after 40 days after sowing, and various plant growth indicators and plant nutrient analyses were measured. The results showed that T2 treatment produced the highest plant height (55.75 cm), fresh weight (34.03 g) and dry weight (5.99 g) (P<0.05). On the other hand, treatment T3 resulted in the highest fresh root weight (5.43 g), dry root weight (1.28 g) and leaf area (46.60 cm2). 2 ). For plant nutrient analysis, T2 exhibited the highest levels of calcium (Ca) (9586.00 mg/kg), magnesium (Mg) (8747.75 mg/kg), iron (Fe) (188.90 mg/kg), zinc (Zn) (63.67 mg/kg), potassium (K) (50337.50 mg/kg), phosphorus (P) (8019.00 mg/kg), whereas T3 had the highest sodium (Na) (571.90 mg/kg) content. Overall, the findings suggest that T2 and T3 treatments have a significant positive effect on plant growth and development compared to the other treatments. Conclusion, significance and impact of study: This study demonstrated the effectiveness of plant growth-promoting bacteria (PGPR) Acinetobacter sp. SR R-12 and organic supplements on enhancing various plant growth parameters and nutrient contents in chilli plants. These findings highlight the potential use of Acinetobactersp. sp. SR R-12 and organic supplements as a sustainable approach to promote chilli plants' growth and nutrient uptake.