I'm assuming you meant subsistence farming? If so then yes, it would be a large problem because they would then not have enough food to feed themselves.
Then it is moving towards earth
Answer: Population growth can be defined as the increase in the number of individuals living within a political or geographical boundary.
The main factors affecting Population growth is basically birth rate, death rate, immigration, and emigration.
The single biggest factor that has contributed to the increase of population in the last 300 years is BIRTH RATE.
Nations with high population growth have low standards of living, while nations with low rates of population growth have high standards of living.