I suggest you contact Dr. Ken Shackel, ([email protected])  from University of California. Davis. He has ample experience  on fruit tree water relations in various California crops.

Dear Shadman

Thank you so much for your answer. 

Best Regards

Dear Juan

Many thanks for your answer.

I will contact him. 

Best Regards. 

You can contact Professor Kang Shaozhong and Du taisheng from China Agriculture University, and also Professor Brent Clothier (New Zealand Institute for Plant & Food Research Limited) and  Professor Elias Fereres (Engineering University of Cordoba, Spain). They did many research works on deficit irrigation for fruit trees such grapevines, apple and peach.

Dear Dazhi

Many thanks for your kindly answer.

ok I will contact them. 

Best Regards. 

the basic principles of deficit irrigation always remained the same whether it is tomato or apple or mango or pistachio. 

Dear Bita, 

There are several studies on the effects of deficit irrigation on pistachio. In those studies you can find useful information about  the specific relationships between plant water stress and reproductive growth and development. Please chek the following article, which should be a good starting point before contacting Drs. Ken Shackel, or Elias Fereres.   

Best regards,

http://www.ucanr.org/files/47996.pdf

Dear Shashi

Many thanks for your answer.

Best Regards. 

Dear Arturo

Thank you so much for the article. 

Quantifying reductions in consumptive water use under regulated deficit irrigation in pistachio. Thank you so much. 

:)

Best wishes