Morphological and Physiological Changes under NaCl Stress in Some Pyrus and Quince Rootstocks

Abstract

In this study, the aim was to determine some morphological, physiological, and biochemical changes in non-grafted plants of OHxF 97, OHxF 333, Fox 11, and BA 29 rootstocks under NaCl stress. NaCl (0 mM, 20 mM, 40 mM, and 80 mM) was applied to the rootstocks planted in 18-liter pots with irrigation water repeated over two years. Under NaCl stress, plant height, plant diameter, and leaf area decreased in all rootstocks. Additionally, Fox 11 and BA 29 rootstocks were more adversely affected by NaCl stress to leaf necrosis. The amounts of chl a, chl b, and total chl decreased in Fox 11 rootstock with moderate and severe stress treatments. Carotenoid content in the leaves, especially under severe stress conditions, showed a decrease in Pyrus rootstocks. Under NaCl stress, the leaves of Fox 11 were rich in proline. MDA content generally increased with NaCl stress compared to the control in Fox 11 and BA 29. Although significant changes in plant nutrients were generally not observed with NaCl, a significant decrease in the amount of K+ in the leaves of Fox 11 was identified. Consequently, Fox 11 and BA 29 rootstocks exhibit sensitivity to NaCl stress, whereas OHxF rootstocks demonstrate greater tolerance.