In vitro responses of grape rootstocks to NaCl

Abstract

An investigation was undertaken to adjudge the in vitro salt tolerance and biochemical changes due to NaCl on four grape rootstocks (Dogridge, SO4, H-144 and 3309C). The in vitro two-node micro-cuttings from the established cultures were sub-cultured on rooting medium comprising Murashige and Skoog (MS) basal medium supplemented with 0.5 μM indolebutyric acid (IBA), 200 mg dm⁻³ activated charcoal and different NaCl concentrations ranging from 0 to 125 mM. The surviving and proliferated cultures were further sub-cultured four times on respective media. Dogridge and H-144 tolerated 125 and 100 mM NaCl, respectively, while SO4 and 3309C survived only up to 75 mM NaCl. Contents of proteins, proline, K⁺ and Na⁺ in tissue increased in all genotypes due to NaCl supplementation, while contents of chlorophyll and total soluble sugars declined. Higher K⁺/Na⁺ ratio was registered in Dogridge and H-144 than in SO4 and 3309C. The relative NaCl tolerance for different grape rootstocks under study could be ranked as Dogridge > H-144 > SO4 and 3309C.