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Nitrous oxide (N₂O) is one of the main greenhouse gases and its emissions from vegetable production systems have brought a sustainability challenge. The objective of this study was to evaluate the potential of reducing N₂O emissions from silt loam soil by mixing nitrogen (N)-rich broccoli (<i>Brassica oleracea</i> var. <i>italica</i>) residue with wheat straw or water-washed wheat straw. An experiment was conducted in randomized complete block design with five treatments; unamended or control (BS), wheat straw (+S), broccoli residue (+CR), broccoli residue and wheat straw (+CR+S) and broccoli residue and washed wheat straw (+CR+Sw) and was replicated four times. The +CR and +S were added at the rate of 3.5 kg and 2.0 kg fresh matter m⁻² and their mixtures, +CR+S and +CR+Sw, were incorporated in 3.5 kg of silt loam soil at 60% water-filled pore space (WFPS) and packed in soil microcosms. Nitrous oxide emissions were measured once a day during the 14-day of study period. Daily fluxes of N₂O were found to be reduced on +CR+W and +CR+Sw when compared to single-amended +CR treatment. Similarly, N₂O fluxes on +CR+Sw (2772 µg N m⁻² h⁻¹) were significantly lower than +CR+S (3606 µg N m⁻² h⁻¹) soon after the amendment but did not vary significantly thereafter. Moreover, the amendment mixture, +CR+S and +Cr+Sw, resulted in lower net N₂O emissions by 73.3% and 74.2%, respectively, relative to +CR treatment. While the results clearly suggest that the +CR+S or +CR+Sw reduced N₂O emissions, it necessitated further studies, possibly by increasing the frequency of sampling to clarify if washed wheat straw would further mitigate N₂O emissions from the vegetable production system.