2D triggers not working Unity 4

Hi everyone, I am as new as it gets to Unity and I can't get this simple trigger collision to work.

I have a game with a player and a key, and I just want the player to be able to pick up the key when they get to it, but it looks like I can't even register the collision in the first place.

Anytime I move my Player over to the key, nothing is logged to the console.

PlayerController script on the Player object

Code (CSharp):

1. using UnityEngine;
2. using System.Collections;
3.  
4. public class PlayerController : MonoBehaviour {
5.  
6.     public float speed = 5.0f;
7.  
8.     void Start () {
9.     }
10.  
11.     void Update () {
12.         if (Input.GetKey(KeyCode.LeftArrow)) {
13.             transform.position += Vector3.left * speed * Time.deltaTime;
14.         } else if (Input.GetKey (KeyCode.RightArrow)) {
15.             transform.position += Vector3.right * speed * Time.deltaTime;
16.         } else if (Input.GetKey(KeyCode.UpArrow)) {
17.             transform.position += Vector3.up * speed * Time.deltaTime;
18.         } else if (Input.GetKey(KeyCode.DownArrow)) {
19.             transform.position += Vector3.down * speed * Time.deltaTime;
20.         }
21.     }
22. }
23.  

Collectible script on the Key object

Code (CSharp):

1.  
2.  
3. using UnityEngine;
4. using System.Collections;
5. public class Collectible : MonoBehaviour {
6.     void Start () {
7.  
8.     }
9.  
10.     void Update () {
11.  
12.     }
13.  
14.     void onTriggerEnter2D(Collider2D trigger) {
15.         Debug.Log ("trigger");
16.     }
17. }
18.  

Inspector view for each object:





Any help would be greatly appreciated. Thanks in advance

 

Collectible script should be on the player.
Also it's not "onTriggerEnter2D" but "OnTriggerEnter2D".

 

Thank you! I used your second suggestion and it works well.

Why do you suggest putting the script on the player, though?