NullReferenceException - Array of Transforms?

hello to all, sorry for my english, it is terrible, i know. I'm a very newbie with unity, and i'm making an android game. My problem is on my shooting script, i've isn't even finished him yet and i'm already getting errors D=

Here is my code:

 using UnityEngine;
 using System.Collections;
 
 public class ShooterBehaviour : MonoBehaviour {
 
 
     public Transform Bullet;
     public int bulletNumber;
     public float fireRate;
     public float currentRate;
     Transform[] bulletList;
 
     void Start () {
         Transform[] bulletList = new Transform [bulletNumber];
         for (int i = 0; i < bulletNumber; i++){
             bulletList[i] = Instantiate (Bullet, transform.position, transform.rotation) as Transform;
         }
     }
 
     void Update () {
         if(Input.GetKeyDown("space")){
             Debug.Log("was pressed!");
             Debug.Log("its time to fire!");
             bulletList[1].gameObject.SetActive(true);
         }
     }
 }

When i press the space bar, i was supposed to fire the first bullet from my array, but instead, i get one nullReferenceException. Does anyone can help me?