Optimizing potash management for enhanced productivity and profitability in black rice (Oryza sativa) cultivation under SRI system

An agronomic investigation was carried out at Instructional-cum-Research Farm of Assam Agricultural University, Jorhat, Assam, during kharif season of 2019–20 and 2020–21 to assess the effect of potash on growth, yield and quality parameters of black rice under organic ecosystem of Northeast India. The experiment was laid out in a randomized block design (RBD) with three replications and twelve different treatments. The experimental data recorded during both successive years revealed that the growth and physiological attributes of organic black rice was significantly influenced by different potassium management practices. Among the different growth and physiological parameters, such as numbers of leaves hill-1, root length, root volume, chlorophyll content, stomatal index and phyllochron index were observed to be significantly higher with the application of recommended dose of fertilizer through banana pseudo stem vermicompost + mustard oil cake at 20 kg ha-1 (T8), which was statistically at par with T6. The lowest values were recorded under the control treatment (T1). Hence, it can be concluded that the integrated application of banana pseudostem vermicompost along with mustard oil cake at 20 kg ha-1 proved to be the most effective potassium management strategy for enhancing the growth, physiological performance and overall productivity of organic black rice under the agro-climatic conditions of North East India.