Purpose: Anthropogenic factors have become the dominant cause of environmental pollution particularly salinity in soils resulting in alternation in plant's physiological and biochemical responses. Salinity-induced stress deleteriously affects crop productivity and has damaged about 6 million hectares in Pakistan. Sodium fluoride (NaF) has emerged as a prominent source of salinity stress and its accumulation in crops has become a major concern worldwide. Seed priming has marked its position as a beneficial technique for salt stress attenuation in various crops. Methods: The current research work was intended to scrutinize the valuable aspect of seed priming with 28-homobrassinolide (HBR) on morphological and biochemical attributes of Pisum sativum L. (pea) plants under NaF stress. P. sativum seeds were subjected to seed priming with three different concentrations of HBR (1 mu M, 5 mu M, and 10 mu M L-1). Results: Sodium fluoride-induced toxicity exhibited a significant decline in the growth of pea plants. The results showed that NaF negatively affected total chlorophyll content (25%), stomatal conductance (28%), and rate of transpiration (46%) and photosynthetic rate (28%) as compared to Control. Nevertheless, seed priming with HBR2 enhanced carotenoid content (65%) and consequent improvement in shoot length (64%), and root's dry biomass (59%) of plants as compared to Control plants were ascertained. All three treatments improved the above-mentioned traits but a maximum increment was observed in response to 5 mu M L-1HBR treatment as compared to the Control. Furthermore, HBR2 improved the gas exchange parameters and proline content (74%) under stress conditions. Conclusions: Although, plants under saline stress demonstrated a decline in morpho-physiological attributes of pea plants but these deleterious effects of salinity were alleviated by HBR priming of the pea seeds.
