According to studies by Yang Tsung-yuan of the department of Chinese at Sao Paulo University, it was back in 1812 (in the Chia- ch'ing period of the Ch'ing dynasty) that 400 Chinese tea workers were invited to Brazil by the then Prince Regent to open up tea plantations, in what must surely be a first for Chinese "agricultural technician diplomacy."
據聖保羅大學中文系教授楊宗元考證，早在西元一八一二年（清嘉慶年間），就有四百名中國茶葉工人應當時巴西攝政王唐將六世之邀，到巴西開墾茶園，算算這應是中國「農技外交」的老鼻祖了。