Changes In Roots And Salt Sensitivity Of Rice Plants Over-expressing Aquaporin

Abstract

In the previous JSPP meetings, we have reported the identification and analysis of barley HvPIP2;1, and some characteristic of transgenic rice plants over-expressing HvPIP2;1. In this presentation, we report the root phenotype and salt tolerance of this transgenic rice plants. Over-expression of HvPIP2;1 increased 1) radial hydraulic conductivity of roots to 140 %, and 2) the mass ratio of shoot to root up to 150%. In these transgenic rice plants under salt stress of 100 mM NaCl, growth reduction was greater than in non-transgenic plants. A decrease in shoot water content was observed in transgenic plants after salt stress of 100 mM NaCl, and they withered and died 2 weeks after salt stress. These results indicated that over-expression of HvPIP2;1 makes rice plants sensitive to 100 mM NaCl.