V. B. KuligodRubeena C. M2016-11-232016-11-232013http://krishikosh.egranth.ac.in/handle/1/87277A field experiment was conducted in the long-term trial on distillery spentwash application established since 2003 at the Main Agricultural Research Station, UAS, Dharwad. The study was carried out during kharif 2012 to know the response of maize to long-term biomethanated spentwash application under Vertisols of Northern transition zone of Karnataka. Experiment consisted of seven treatments and 3 replications. Results revealed that long-term application of 1½ recommended nitrogen through spentwash was superior with respect to the growth parameters like plant height, chlorophyll content and dry matter production and yield parameters like cob length, cob circumference, cob weight, number of rows per cob, number of seeds per row, number of seeds per cob and test weight. Both growth and yield parameters complemented each other in realising higher grain and stover yield. Spentwash application had also increased the nutrient uptake by the maize. Long-term application of spentwash improved the physico-chemical properties of the soil. Application of spentwash to supply 1½ recommended nitrogen significantly reduced the soil bulk density and increased porosity, aggregate stability and maximum water holding capacity. The soil reaction and soluble salts were not adversely affected by the long-term application of spentwash. Soil salinity remained within the critical limit of four dSm-1 even after nine years of spentwash application. The available nutrient status of soil was found to be higher in the plots applied with 1½ recommended dose of nitrogen through spentwash. The soil dehydrogenase and phosphatase enzyme activities increased due to the long-term spentwash application. Application of distillery spentwash to supply 1½ times recommended nitrogen recorded the highest net returns and B:C ratio.Thesis