Google Scholar search after 2010..

http://scholar.google.com/scholar?as_ylo=2010&q=water+use+efficiency+tropical+plants&hl=en&as_sdt=0,10

for example, have attached one article

Dear Timoth,

contact Morgana Vaz da Silva. She worked with in water use efficiency at the Federal University of Viçosa - Brazil.

E-mail: [email protected] 

Dear Timothy Acidri

I recommended that you see the publications of Prof. Walter de Paula Lima (ESALQ/USP -Brasil) his Curriculu Vitae adress: http://lattes.cnpq.br/9771967944780464