Phenotypic evaluation of transgenic peas (Pisum sativum L.) harboring AtNHX1 demonstrates stable gene expression and conserved morphology in subsequent generations

Abstract

In recent years, transgenic approaches have played a significant role in improving traits that help plants overcome abioticstresses. Combined gene discovery and functional genomics have helped identify diversified mechanisms and gene families, whichimproved productivity under various abiotic stresses. We report on the genetic stability and persistent morphological features oftransgenic pea (Pisum sativum L.) plants harboring the dicistronic vector construct pG0229MASnhx1/luc over five generations. Inaddition to salt stress tolerance, the transgenic plants showed frost tolerance compared to wild-type (WT) plants. Frost tolerance ofAtNHX1 transgenic pea plants was unexpected and needs further investigation. We report morphological and molecular characteristicsof transformed plants after long-term storage at 30–50 °C. The transgenic plants were morphologically stable and genetic stability ofintegrated genes was confirmed prior to and after transfer of plants to a glasshouse. Leaf size, shape, and color, plant height, number oftendrils, flower shape, pod shape, and grains were morphologically similar to the WT counterpart in all transgenic generations. This isthe first report showing the genetic stability of transgenic pea plants harboring the salt stress tolerance gene (AtNHX1) from Arabidopsisthaliana in subsequent generations over a period of 6 years.