Influence of sodium and potassium on morphological growth responses of Ziziphus mauritiana and Syzygium cuminii under controlled conditions

Abstract

Ziziphus mauritiana and Syzygium cumini (Black plum) are important trees of India and Pakistan, where poor irrigation practices are responsible for the soil salinity. Their study was conducted in the wire-house of the Department of Forestry and Range Management, University of Agriculture, Faisalabad, during spring 2019 to assess the growth of these two species against salinity. About 6 to 8-month-old seedlings of uniform size were used for the trial. Five NaCl salinity levels were developed artificially by maintaining their EC, such as T₀= Control without NaCl- salinity (EC 1.25 dSm^-1), T₁= EC 05 dSm^-1 with NaCl, T₂= EC 10 dSm^-1 with NaCl, T₃: EC 15 dSm^-1 with NaCl and T₄= EC 20 dSm^-1 with NaCl. The results showed significant differences across various salinity levels. The shoot length was recorded as the maximum in Z. mauritiana (131.62 cm) and Syzygium cuminii (96.846 cm) without salinity, but in treatment (T₄), where NaCl concentration was 20 dSm^-1, it was (33.98 cm) and (21.722 cm) respectively. Diameter was recorded as maximum without NaCl-salinity application in Z. mauritiana (5.374 mm) and S. cuminii (4.164 mm). The minimum diameter was recorded in T4 i.e. (1.268 cm) and 4.144 cm. Similarly, all other parameters showed the same trend. Low K⁺ concentration was observed while higher Na⁺ in both species. Z. mauritiana is a moderately fast-growing species that showed luxurious growth in comparison with S. cuminii under saline conditions. It was concluded that Z. mauritiana is more tolerant the salinity as compared to S. cuminii.