Yellow vegetable.
The item id for Corn in unturned is 335. You can use this ID with the commands below to spawn the item, give it to a player or buy it on a modded economy server.
Useable: Consumeable
Size_X: 1
Size_Y: 2
Size_Z: 0.35
Quality_Max: 50
Food: 20
Water: 10
Actions: 1
Action_0_Type: Blueprint
Action_0_Source: 336
Action_0_Blueprints: 1
Action_0_Blueprint_0_Index: 0
Action_0_Key: Craft_Seed
ConsumeAudioClip: Sounds/EatCrunchy.mp3