Biotechnology is a very research oriented field and since you have completed your M.Tech in Biotechnology you should go for this field only. As you have done B.Tech in Agriculture Engg, you can try for research in agricultural biotechnology. In India agriculture is the main topic of Biotechnological research, but mostly in government institutes. So keep looking for jobs in agribiotech companies, if you immediately want a job. Some agribiotech and seed manufacturing companies are available in our country.

If you want to go for research in agriculture biotechnology try to get registered yourself for PhD from any of the good institutes.

You may discuss this topic further at: forum.CareerAge.com

Hope that helps.
CareerAge Counselor