Kandali, Gayatri GoswamiDas, Dipika2024-09-232024-09-232023https://krishikosh.egranth.ac.in/handle/1/5810214812A pot culture experiment was carried out to study the “Phosphate dynamics in Maize (Zea mays) as influenced by zeolite enabled nano phosphatic fertilizer” during 2022-23. The aim of the experiment was to study the phosphate dynamics in maize and the release pattern of phosphorus for a period of 75 days at 15 days interval taking five treatments including treatments with Zeolite based nano-P fertilizers which was already synthesized and characterized. The treatments with nano fertilizers were 100% RDP through nano P fertilizer and reduced doses of 60% and 80% RDP through nano P fertilizer. These treatments were compared with an absolute control and a treatment where recommended dose of P was applied through chemical fertilizer taking the recommended dose of maize as the rate of phosphorus application. Three different types of soil collected from various locations of Jorhat, Titabar and Majuli representing different textural classes viz. silty clay loam, clay loam and sandy clay loam were taken for the study. Treatment receiving 100% RDP through nanofertilizer showed minimum concentration of available P from 0 days upto 15 days and thereafter it gradually increased reaching its maximum value in 60 days of interval period. Similar trend were observed for other treatments receiving nano P with reduced doses. Such trend was same for the two soils with textures sandy clay loam and silty clay loam whereas clay loam soil showed a gradual increase in available P throughout the cropping period reaching its peak at 75 days and thereafter declined. Highest concentration of P at 60 days interval was found in treatment receiving 100% RDP through nanofertilizer which was statistically higher than treatment receiving RDP through SSP. Significant difference in P release was found between 100% nano P and treatment receiving 60% of RDP through nano fertilizer in all the three type of soil. No significant difference in P release was found between treatments receiving 60% and 80% RDP through nano P. Significant difference in phosphorus content and uptake in grain and straw was found between absolute control, RDP through SSP and RDP through nano P fertilizer. However no significance difference was found between the treatments receiving 100% RDP through nano and the reduced doses of 60 % and 80% RDP through nano P. This trend followed in all the three types of soil. Correlation coefficients among soil available phosphorus concentration at 15 days with corresponding plant phosphorus concentration at 15 days was found to be non significant. However the same was found to be highly significant during the other days of interval.The first order kinetic constant was found to increase from T2 to T5 which might be due to less fixation of P by soil components. In case of second order kinetics, the decrease in rate constant value means increase in the release of P, which is dependent upon both soil solution and soil matrix. The parabolic diffusion equation was best fit for describing the P release as compared to the other two kinetic models.EnglishThesis