Seed priming with karrikinolide improves growth and physiochemical features of coriandrum sativum under cadmium stress

Cadmium (Cd) pollution in agricultural sites is an international issue which has been increasing continuously. It necessitates searching techniques for alleviation of Cd stress in crop plants. An in vitro experiment was performed to observe the role of karrikinolide (KAR1) in extenuation of cadmium (Cd) stress in Coriandrum sativum L. (coriander). Coriander seeds were primed with three different level of KAR1 solution (10−4 M, 10−6 M and 10−8 M) and kept in petri plates containing Cd spiked solution for 15 days. Cadmium-driven toxicity exhibited noticeable decreased growth in coriander seedlings. The results showed that Cd enhanced oxidative markers such as of synthesis of malondialdehyde, reactive oxygen species and extent of electrolyte leakage. Moreover, Cd negatively affected gas exchange attributes and amount of the relative water content in stressed seedlings. Nevertheless, seeds priming with 10−6 M KAR1 resulted improved germination rate and subsequent enhancement in photosynthesis, growth and biomass production of developed seedlings. Therefore, seed primed with KAR1showed improved relative water content, leaf osmotic potential and membranous stability index. Additionally, KAR1 treated seedlings showed improved gas exchange attributes and metal tolerance index. In summary, these findings advocate that KAR1 enhances plant stress tolerance by modulating the antioxidative machinery and reducing the level of stress biomarkers