There are no link between government job and private college. For a government job one had to satisfy the condition or eligibility of the examination. If you satisfy it then you are eligible and it doesn't depend on the status of your college.

For most of the government exams the eligibility is a mere graduation in any subject from any recognized university.

For most of the agricultural officer jobs, one have to score at least 50% marks in three BSc Agriculture course.

To know more about Agricultural Officer job visit the link below:

https://www.careers360.com/careers/agriculture-officer

I hope this answer helps. All the very best for your future endeavors!