Effect of Zinc Solubilizing Bacteria (ZSB) in Paddy Growing Areas of Namchi District, Sikkim, India

Abstract

Zinc Solubilizing Bacteria (ZSB) play a vital role in improving zinc availability for rice, particularly in zinc-deficient soils. When applied as a root-dip treatment, ZSB help facilitate the conversion of insoluble zinc compounds into bioavailable forms, making it easier for rice plants to absorb this essential micronutrient. The present study was conducted in the year 2021-22 to highlights the clear advantages of technology-based agricultural practices over farmer practices in terms of crop performance, soil fertility, and economic returns. The trials were conducted in the paddy-growing areas of Rabitar and Sumbuk Village in the Namchi District of Sikkim to manage zinc (Zn) through root-dip treatment of paddy seedlings of Var. Sikkim Dhan-1. A mud slurry bed measuring 45 m² was prepared in one corner of the field. Approximately 5 kg of finely ground FYM, along with 3.5 kg/ha or 500 ml of the liquid formulation Zinc Solubilizing Bacteria (ZSB), was thoroughly mixed in the slurry bed. The roots of the paddy seedlings, free from adhering soil, were dipped into the slurry mud and incubated for 2 hours before transplanting in the entire field. Before transplanting the seedlings field was prepared following organic packages and practices of paddy. The Net return and B:C ratio were calculated for both experiments i.e. technology and farmers' practice. The results show that the average plant height at the harvest stage was 112 cm compared to the farmer’s practice of 108 cm. Other parameters, such as the average number of tillers per hill and the average number of panicles per hill, were 14.72 and 13.14, respectively, compared to the farmer’s practice of 11.33 and 10.30, respectively. The average yield was found to be 3.5 tons per hectare, compared to the farmer’s practice yield of 2.52 tons per hectare. The results also indicated that the soil's available zinc before cultivation was 0.84 mg/kg, whereas after harvest, there was a slight increase in the soil's available zinc, measuring 1.26 mg/kg. All other soil parameters also showed slightly higher nutrient availability compared to the farmer’s practice. The B:C ratio was 2.62 for this technology and 1.69 for the farmer’s practice. Higher organic carbon, phosphorus availability, and zinc levels indicate better soil health and nutrient retention under advanced management techniques. Net return and B:C ratio emphasize the profitability and efficiency of technology-driven farming.