In an ecosystem, the producers refers to the green plants, which are capable of making their own foods with the help of energy from the sun through a process called photosynthesis. The food made by the producer is the major source of food on which other living organisms depend. Also, during the process of photosynthesis, the producers usually release oxygen, which is used by humans to carry out the process of respiration. If there are no producers in the ecosystem, then there will not be food for other organisms to feed on and this will ultimately leads to the elimination of all living organisms from the earth. Also, there will be no oxygen to carry out respiration.