Lentil is an important grain legume crop which is mostly grown on marginal soils that hamper its productivity. Improvement of salt tolerance in lentils is considered to be a useful strategy of utilizing salt-affected lands in an economic manner. This study was conducted to evaluate the effectiveness of seed priming using silicic acid and humic acid both seperately and in combination to improve salt stress tolerance among three different lentil varieties: IPL-316 (tolerant), PSL-9, and PDL-1 (susceptible). The concentrations and durations of treatments were standardized under the normal condition and the salinity stress condition. Salt stress hindered seedling emergence and biomass production and accelerated Na⁺ toxicity and oxidative damage at the seedling stage in untreated seeds. Nevertheless, chemical priming improved early seedling emergence, increased root length, shoot length, and seed vigor index I and II, and reduced the mean germination time. A significant quantitative change in biochemical parameters under normal and salinity stress conditions was observed in IPL-316,viz. Specifically, for IPL-316, the following parameters were observed (values under the normal condition and values under salt stress conditions, respectively): chlorophyll-a (16 and 13 mg/g Fw), chlorophyll-b (25 and 16 mg/g FW), total chlorophyll content (42 and 30 mg/g FW), relative leaf water content (92% and 82%), total soluble sugars (26 and 33 ug/g FW), free amino acid (10 and 7 mg/g FW), total phenol (26 and 24 mg of GAE/g FW), total protein (35 and 29 mg/g FW), carbohydrate (208 and 173 mg/g FW), superoxide dismutase (SOD) (29 and 35 unit/min./g FW), proline (0.28 and 0.32 u mol/g FW), catalase (CAT) (84 and 196 unit/mL/g FW), and peroxidase (POX) (217 and 738 unit/mL/g FW). Furthermore, histochemical analysis of H₂O₂ and O²⁻, micronutrients, and macronutrients also increased, while malondialdehyde (MDA) (0.31 and 0.47 nmol/mL FW) content decreased using silicic and humic acid priming under salt stress conditions. The combination of silicic and humic acids improved seedling growth and reduced oxidative damage in lentil plants under salt stress conditions. The combination of silicic and humic acid priming hastened seedling emergence, seed quality parameters, and biochemical parameters under salt stress over respective control. To the best of our knowledge, this is the first report of integrated chemical priming in lentils for salinity stress. In conclusion, chemical priming using a combination of silicic and humic acid performed better in terms of seed quality due to enhanced antioxidant machinery, better membrane stability and osmolyte protection, and enhanced nutrient uptake under salt stress conditions.

Seed priming has emerged as an innovative and economical technique to elevate seed quality, fostering uniform, swift, and robust germination under both stress and non-stress conditions. This study endeavors to scrutinize the effects of organic (silicic acid, SA) and inorganic (humic acid, HA) acids, alongside their synergistic combinations, on seed quality parameters in three distinct lentil (Lens culinaris) genotypes: IPL-316 (tolerant), PSL-9, and PDL-1 (sensitive). Critical parameters assessed encompass germination percentage, root and shoot length, seed vigor indices I and II, and dry weight under meticulously controlled laboratory conditions. The priming agents were standardized across a spectrum of concentrations and durations. Sterilized seeds were immersed in silicic acid (1, 2, 3, 4, and 5 mM), humic acid (100, 200, 300, 400, 600, 800, and 1000 ppm), and their combinations over varying durations (2 to 18 hours), including control and hydropriming treatments. Following treatment, seeds were air-dried and subjected to growth assessments. The findings reveal that priming significantly bolsters early-stage plant growth across all three lentil genotypes, with the combined application of silicic and humic acids yielding remarkable enhancements in all seed quality parameters, intricately influenced by genotype and treatment combination.

Seed priming enhances seed quality, and is crucial for plant development under stresses like salinity, heat, and drought. This study examines silicic and humic acid (HA+SA) treatment on lentil seeds under salinity stress, focusing on susceptible (PSL-9, PDL-1) and tolerant (IPL-316) varieties. Priming agents included silicic acid (3mM, 18 hours), humic acid (600 ppm, 18 hours), and their combination (100 ppm+1mM HA + SA, 16 hours). Seedling survival under salinity stress (100, 120, 140 mM) was evaluated under hydroponics conditions. Salinity stress significantly reduced seed quality and physiobiochemical parameters in unprimed control seeds, especially in PDL-1 and PSL-9, compared to IPL-316. Higher seedling percentage and growth were noted in IPL-316 seeds primed with HA + SA under salinity stress. This improvement is due to better photoactivation of PS-I and PS-II, ROS activity, and antioxidant availability, enhancing seedling growth under salinity. The study highlights the importance of SA and HA priming agents in promoting seedling growth under salinity stress.

Background: Lentil is second most important nutritionally dense pulse crop of India due to its ability to fix nitrogen, helps to maintain soil fertility and increase yield of other crops grown in rotations. Seed priming is a good innovative technology for improvement of emergence and plant stand under various stress conditions and also could enhance various defense mechanisms in seeds against biotic and abiotic stresses. The present study aimed to examine the effect of seed priming with silicic acid (3 mM @18 hr), humic acid (600 ppm @18 hr) and combination of humic and silicic acid (100 ppm + 1 mM @ 16 hr), that may reduce harmful effect of stress at seedling stage and improve early seedling vigor. Methods: In this field-laboratory investigation during 2022-2023, seed quality and yield quality attributing parameters i.e. germination percentage, seed vigor index-I and II, total chlorophyll, emergence percentage, final plant stand, final plant stand emergence, plant height, secondary branches, tertiary branches, number of pod per plant, average number of pod per plant, pod cluster, seed yield per plot and yield per plot were recorded in both laboratory and field conditions. Result: The results demonstrated a positive effect of seed priming on seed quality parameters against the stress. The highest seed quality and yield quality attributing parameter was recorded in treatment (T5) combination of humic and silicic acid as compare to control. The chemical priming with combination of humic and silicic acid was found to be most effective treatment to enhance plant stand establishment against stress.

Lentil (Lens culinaris Medik.) is a nutritionally valuable pulse crop that enhances food security and soil fertility through biological nitrogen fixation. However, its productivity is often constrained by poor germination and uneven seedling establishment. This study investigated biochar and humic acid as sustainable seed-priming agents to improve lentil seed performance. After preliminary optimization, the most effective concentrations of both agents were evaluated under controlled laboratory conditions. Germination percentage, seedling length, vigour indices, chlorophyll content, and oxidative stress response (DAB assay) were assessed. Both treatments significantly enhanced seed and seedling traits compared with unprimed controls (p < 0.05). Biochar priming increased germination by 14.7%, seedling length by 26.3%, and vigour index by 32.5% over control, alongside higher chlorophyll content and reduced hydrogen peroxide accumulation, indicating improved physiological efficiency and stress mitigation. Humic acid also improved performance, though to a lesser degree. The results demonstrate that biochar and humic acid priming enhance seed vigour and metabolic activity by promoting stress regulation and efficient energy utilization. Overall, biochar emerged as the superior and eco-friendly option for improving germination and early growth in lentil, offering a practical approach for sustainable pulse production and climate-resilient agriculture.