Unity Dynamic Batching

 public class test1 : MonoBehaviour {

     public GameObject prefab;

     void Start()
     {
         for (int i = ; i < ; i++)
         {
             GameObject tmp =  Instantiate(prefab) as GameObject;

             //Make sure you don't clone the material at runtime. If that's the case, then every object will have its own duplicated material.so they can't dynamic batching

             //For example, this kind of code causes a cloning:

             //renderer.material.color = Color.white;

             //In that particular case, vertex coloring is a workaround to change the color without duplicating the material.

             //Try to use only renderer.sharedMaterial or renderer.sharedMaterials.
             tmp.GetComponent<Renderer>().material.color = Color.red;
         }
     }
 }