Effects of cycocel on growth, some physiological traits and yield of wheat (Triticum aestivum L.) under salt stress

Abstract

In order to investigate changes in sodium ion (Na⁺), potassium ion (K⁺), dry matter mobilization and grain filling period of wheat (<em>Triticum aestivum</em> L.) under salinity stress, a factorial experiment was conducted based on randomized complete block design with three replications. Factors were salinity at four levels [no-salt (S₀) and salinity of 25 (S₁), 50 (S₂) and 75 (S₃) mM NaCl, equivalent of 2.3, 4.61 and 6.92 dS m⁻¹, respectively] and four cycocel levels [without cycocel (C₀) and application of 400 (C₁), 800 (C₂) and 1200 (C₃) mg L^-1 cycocel)]. Results showed that salinity stress decreased grain yield, chlorophyll index, grain filling period, stomata conductance and relative water content in plant shoots. But grain filling rate and dry matter remobilization from shoots increased. Application of cycocel at C₃ level led to the reduction of 36.36% and 5.75% in dry matter remobilization from shoot and stem, respectively. In the case of mineral content, Na⁺/K⁺ ratio was increased with increasing salinity level. At all salinity levels, cycocel application resulted in lower Na⁺ content and Na⁺/K⁺ratio. Higher K⁺ accumulation in the cycocel treated plants, resulted in a low Na⁺/K⁺ratio leading to their efficiency in salinity tolerance. It was concluded that cycocel can be a proper toolfor increasing wheat yield under salinity condition.