Enhanced nitrogen assimilation in transgenic mustard (<i style="mso-bidi-font-style:normal">Brassica</i> <i style="mso-bidi-font-style:normal">juncea </i>L.) overexpressing high affinity sulfate transporter gene

Abstract

Nitrogen is an essential macronutrient needed by the plants to grow and survive. Due to the metabolic coupling between nitrogen and sulfur metabolism, sulfur deficiency in plants leads to nitrogen deficiency as well. In the present paper, effect of higher assimilation of sulphur, because of overexpression of LeST<i style="mso-bidi-font-style:normal"> </i>1.1 gene (high affinity sulfate transporter), on nitrogen uptake and assimilation was studied in mustard [<i style="mso-bidi-font-style:normal">Brassica juncea</i> (L.) Czern. & Coss.] cv. Pusa Jai Kisan. Higher nitrogen uptake under both sulfur insufficient (50 µM) and sulfur sufficient (1000 µM) conditions was observed in the transgenic plants in comparison with untransformed plants. The transgenic plants also had higher nitrate reductase, soluble protein and total nitrogen content. The results thus obtained demonstrate a positive impact of overexpression of LeST1.1 gene on the uptake and assimilation of nitrogen in <i style="mso-bidi-font-style:normal">B. juncea</i>.