This guide covers a set of high-quality sources of information for Agriculture and Agricultural economics
It is a good starting point for your research.
Web of Science
The most important source in agricultural chemistry, agrochemicals, foods. SciFinder contains the complete Chemical Abstracts since 1907, including substance search, substructure search, reaction search, etc.
Scopus is the largest abstract and citation database of peer-reviewed literature: scientific journals, books and conference proceedings.
Google's search engine for scholarly and scientific literature.