This version of Unity is unsupported.
Removed

Component.particleSystem

Obsolete Property particleSystem has been deprecated. Use GetComponent<ParticleSystem>() instead. public Component particleSystem;

Description

The ParticleSystem attached to this GameObject. (Null if there is none attached).

using UnityEngine;

public class Example : MonoBehaviour { void Start() { GetComponent<ParticleSystem>().Emit(5); } }