Salinity Effects on Potassium Accumulation and Transporters Expression in Grape (Vitis vinifera L.). Nayer Mohammadkhani1٭, Reza Heidari2 and Nasser Abbaspour2

Abstract

<span style="font-family: Calibri;"><span style="font-size: medium;"><span lang="EN-MY">Hydroponically grown </span><span lang="EN-MY">ten grape genotypes </span></span><span lang="EN-MY"><span style="font-size: medium;">(<em>Vitis vinifera</em> L.) were treated with different concentrations of NaCl. Chawga genotype accumulated K</span>^{<span style="font-size: small;">+</span>}<span style="font-size: medium;"> in its root and shoot even at high salinity</span></span><span lang="EN-MY"><span style="font-size: medium;">. The correlation between Na</span>^{<span style="font-size: small;">+</span>}<span style="font-size: medium;"> and K</span>^{<span style="font-size: small;">+</span>}<span style="font-size: medium;"> concentrations in root and lamina of all genotypes was negative (<em>P<0.05</em>, r</span>^{<span style="font-size: small;">2</span>}<span style="font-size: medium;">=-0.841) except for Chawga (<em>P<0.01</em>, r</span>^{<span style="font-size: small;">2</span>}<span style="font-size: medium;">=0.998). K</span>_{<span style="font-size: small;">m</span>}<span style="font-size: medium;"> calculated for K</span>^{<span style="font-size: small;">+</span>}<span style="font-size: medium;"> and Na</span>^{<span style="font-size: small;">+</span>}<span style="font-size: medium;"> uptake into root and shoot of Chawga showed that K</span>^{<span style="font-size: small;">+</span>}<span style="font-size: medium;"> and Na</span>^{<span style="font-size: small;">+</span>}<span style="font-size: medium;"> compete to enter the plant, especially through roots. Chawga accumulated K</span>^{<span style="font-size: small;">+ </span>}<span style="font-size: medium;">in plant parts in spite of external higher Na</span>^{<span style="font-size: small;">+ </span>}<span style="font-size: medium;">due to increasing</span><span style="font-size: medium;">salinity.</span><span style="font-size: medium;">Two KUP/KT/HAK-type potassium transporters are expressed highly in the grapevine during stress. <em>VvK1.1</em> could play a major role in K</span>^{<span style="font-size: small;">+ </span>}<span style="font-size: medium;">loading into grape tissues. Under salinity stress the expression of <em>VvKUP1</em> and <em>VvKUP2</em> transporter and <em>VvK1.1</em> channel increased significantly (<em>P<0.05</em>) in roots and leaves of Chawga genotype, but that increase was higher in roots than in leaves. </span></span></span>