Improvement of Salt Tolerance in Putatively Transgenic Rice Plants Overexpressing AFP1, a Vacuolar H~+-Pyrophosphatase

摘要

Alleviating salt stress in plants is an important aspect of crop improvement. Salt stress affects plant growth and development in many different ways. To maintain growth and productivity plants must adapt to stress conditions and exercise specific tolerance mechanisms. In the present study, AVP1, a vacuolar H~+-PPase gene from Arabidopsis thaliana was overexpressed in rice (var-Vikas) by Agrobacterium mediated In Planta transformation technique. To screen putative T_1 plants for salt tolerance, stringent salt screening test was followed and root and shoot growth of T_1putative transformants was used as a selection criterion. Some of the transgenics showed significantly higher root and shoot growth compared to wild type. PCR analysis confirmed the integration of the transgene in the rice genomic DNA. Physiological studies such as chlorophyll (Chi) estimation, membrane integrity, cell viability tests were also conducted to assess their levels of tolerance at T_1generation. Some of the T_1 transformants showed lower percent reduction in Chi content, higher cell viability after NaCl treatment compared to wild type (WT). These results clearly demonstrate that transgenic rice plants overexpressing AVP1 a vacuolar H~+ proton pump have better salt-tolerance.