The researchers studied how different types of organic manure and levels of nitrogen affected the growth and yield of Rabi maize in a rice-maize cropping system. They tested three organic manure options and seven nitrogen levels in a split plot design over two years. Results showed that using green manure or farm yard manure significantly improved plant growth and grain yield compared to no manure. The residual effect of nitrogen levels applied to rice did not significantly impact maize growth, but applying graded levels of nitrogen to maize increased plant height and dry matter production.