Effect of exchangeable sodium percentage on the growth and mineral composition of ‘Thompson Seedless’ grapevines

Abstract

One-year-old rooted vines of ‘Thompson Seedless’ were grown in pots to assess their response to 6 levels of soil exchangeable sodium percentage (ESP), viz. 10, 15, 30, 45, 60 and 75. The growth of the vine was depressed with increasing levels of ESP. Symptoms of leaf burn appeared 4–5 weeks after sprouting at ESP levels of 45, 60 and 75. The concentration of leaf Na associated with injury symptoms was 0.55%. Mineral analysis of leaf, shoot and root samples showed increase in leaf N and decrease in shoot N with increasing ESP. No consistent trend was observed with respect to root N. Concentrations of P, K, Ca and Mg were reduced significantly with increasing ESP, except that of Mg in leaves and P in roots and shoots. Na concentration increased in all parts of the vine.