**Acknowledgements**

I would like to thank Dr. Praneet Damrongphol, Mahidol University for providing advice on the experimental designs and constructive comments on this manuscript, Dr. Hirobumi Suzuki, Olympus Corporation for technical assistance, Dr.Yuvarin Boontop, Department of Agriculture, Bangkok for molecular data analysis and Dr. Parichart Laksanawimol, Chandrakasem Rajabhat University for field assistant. I especially thank Dr. Steven Wing for manuscript correction.

This study was financially supported by the Thailand Research Fund (TRF) (MRG5580177) and Kasetsart University Research and Development Institute (KURDI).
