Combined effect of potassium fertiliser and potassium-releasing bacteria on the productivity of kodo millet under irrigated conditions

Potassium (K) is an essential macronutrient that is indispensable for sustaining crop growth, improving productivity and enhancing tolerance to environmental stresses. However, a large proportion of soil potassium remains unavailable to plants due to its occurrence in insoluble mineral forms. Potassium releasing bacteria (KRB) offer a sustainable approach to enhance potassium availability and improve nutrient-use efficiency. A study was undertaken across two consecutive rabi seasons (2024 and 2025) to assess the response of irrigated kodo millet to potassium fertilisation and potassium-releasing bacteria (KRB). Seven treatments comprising different potassium fertiliser levels (10 and 20 kg K ha-1), KRB inoculation (5 kg ha-1) and foliar application of 0.5 % K₂SO₄ were evaluated in a randomised block design (RBD) with 3 replications. The pooled results revealed that the integrated application of 40 : 20 : 10 kg NPK ha-1 + KRB at 5 kg ha-1 + 0.5 % K₂SO₄ foliar spray (T₆) significantly enhanced growth and yield attributes, resulting in the highest grain yield (1851 kg ha-1), straw yield (3270 kg ha-1), dry matter production (4895 kg ha-1) and harvest index (0.32). The same treatment also recorded the highest potassium uptake (69.08 kg ha-1), soil bacterial population (17.54 × 10⁶ CFU g-1 soil) and superior economic returns with a net profit of ₹24090 ha-1 and a BCR of 1.69. The study demonstrates that integrating moderate potassium fertilisation with KRB and foliar potassium supplementation is an effective and economically viable strategy for enhancing the productivity and profitability of irrigated kodo millet cultivation.