This study evaluated the chemical composition of two maize varieties at different levels of green manure application. The bucket experiment was laid in 2 × 3 factorial arrangement comprising two maize varieties (Oba super 2 and Suwan I) and three green manure application levels (0, 6.3 and 12.6 t/ha). The results showed that Oba super 2 had a lower (p < 0.05) Crude Protein (CP) (8.91 %) content, but had a higher (p < 0.05) ether extract (8.83 %) and ash (9.83 %) contents as compared to Suwan I. Maize fertilised with 6.3 t/ha of green manure had the highest CP (10.13 %) and ash (9.96 %) contents. Interaction effect of variety and level of green manure application showed that the least CP content (7.61 %) was recorded for unfertilised Oba Super 2 maize, whereas the highest CP content (10.21 %) was recorded for Suwan I maize fertilised with 12.6 t/ha of green manure. There were no significant (p > 0.05) differences in the Neutral Detergent Fibre (NDF), Acid Detergent Lignin (ADL), hemicellulose and cellulose contents of the two maize varieties evaluated. However, the Acid Detergent Fibre (ADF) content was significantly (p < 0.05) higher (32.33 %) in Oba Super 2 variety. The rising amounts of green manure applied significantly (p < 0.05) increased both the NDF and ADF. There was no consistent variation in the NDF content as influenced by interaction of both factors with the highest (60.67 %) NDF content recorded for unfertilised Oba Super 2 maize. Calcium, potassium and phosphorus contents declined with the increasing amount of green manure added. Our results show that the green manure application improved the nutritional qualities of the planted maize and should be used in practice.
