Showing 2 results for Nigella
Zeynab Savaedy, Abdol Mehdi Bakhshandeh, Seyed Ataollah Siadat, Amin Lotfi Jalal Abadi, Seyed Amir Moosavi,
Volume 10, Issue 2 (9-2023)
Abstract
Extended abstract
Introduction: Deterioration reduces the quality of seeds. Oilseeds like Nigella are highly susceptible to seed aging. Seed priming enhances the quality of deteriorated seeds by improving germination indices and increasing the activity of antioxidant enzymes. This research aimed to investigate the extent of damage caused by accelerated aging treatment on the germination characteristics and antioxidant enzyme activity of Nigella seeds and the possibility of mitigating the adverse effects of aging through hormonal priming with cytokinin.
Materials and methods: This research was carried out in the form of a completely random basic design with four replications in the seed technology laboratory of Khuzestan University of Agricultural Sciences and Natural Resources in 2017. The treatments included hormonal priming with cytokinin at five levels (0 (control), 10, 20, 40, and 80 m/l) for two durations (12 and 24 hours), and aging under 100% relative humidity and a temperature of 45 °C at five levels (no aging, 24, 48, 72, and 96 h).
Results: The analysis of variance results indicated that germination indices were only influenced by main and two-way effects at the 5% and 1% probability levels, while the three-way interactions, including aging, hormone concentration, and priming duration, were significant for plant growth and longitudinal and weight indices at the 1% probability level. Furthermore, it was evident that the priming treatment mitigated the negative effects of aging, with the concentration of 10 milligrams per liter of cytokinin for a duration of 12 h having the most significant impact among the hormone concentrations used on the measured traits. The highest germination percentage (88%) and the lowest germination percentage (63.33%) were observed at concentrations of 10 and 80 mg/l, respectively. The use of cytokinin at optimal concentration improved catalase activity and protein levels. The results showed that in the control conditions, the activity of the catalase enzyme was 0.76 units per mg of protein and the amount of protein was 0.51 mg/g, which reached 0.97 units per mg of protein and 0.79 mg/g with seed priming.
Conclusion: Based on the results obtained from this research, aging led to a reduction in germination indices, the activity of antioxidant enzymes, and seed protein content. The best treatment applied was cytokinin hormone priming for aged Nigella seeds at a concentration of 10 mg/l for 12 h. According to the results, the application of cytokinin at its optimal concentration (10 mg/l) improved the catalase enzyme activity and protein content. Therefore, it can be suggested that hormonal priming with cytokinin helps mitigate the adverse effects of aging in Nigella plants.
Highlights:
- The impact of hormonal priming with cytokinin at concentrations of 10, 20, 40, and 80 mg/L on aged Nigella seeds was investigated.
- The use of a concentration of 10 mg/l of cytokinin hormone for 12 hours was introduced as the best treatment.
- Cytokinin was introduced as a significant hormone that enhances the activity of antioxidant enzymes and physiological traits in aged Nigella seeds.
Akram Oraki, Ehsan Shahbazi, Keramatollah Saeidi, Fariba Rafiei,
Volume 12, Issue 2 (10-2025)
Abstract
Objective: This study evaluated the effects of polyethylene glycol (PEG)-induced drought stress on germination traits, seedling growth, and seed vigor across 24 Nigella sativa genotypes to identify drought-tolerant and -sensitive genotypes.
Method: The experiment was a factorial arrangement based on a completely randomized design (CRD) with three replications, conducted at the Crop Physiology Laboratory of Shahrekord University. The factors comprised 24 N. sativa genotypes and five drought levels induced by PEG at osmotic potentials of 0 (distilled water, control), -0.2, -0.3, -0.4, and -0.6 MPa. Measured traits included germination percentage and rate, mean germination time, root and shoot length, seedling length, seedling fresh and dry weight, and seed vigor.
Results: Analysis of variance (ANOVA) revealed that genotype, drought, and their interaction significantly affected all germination and early seedling growth traits. The strongest positive correlations were observed between seed vigor and seedling length, seedling length and root length, and seed vigor and root length. Principal component analysis (PCA) of the nine traits identified three components with eigenvalues >1, accounting for 87.91% of the total variance. Based on the PCA biplot and Ward's hierarchical cluster analysis, the genotypes were classified into three groups: tolerant (genotypes 3, 8, 11, 24), semi-tolerant (genotypes 1, 2, 9, 12, 14, 17), and sensitive (the remaining 14). Multivariate tests (Pillai's trace, Wilks' lambda, Hotelling-Lawley trace, and Roy's largest root) confirmed highly significant differences among the three groups (p < 0.01), validating the classification robustness.
Conclusions: The findings reveal significant genetic diversity among N. sativa genotypes under drought stress. Genotypes 3, 8, 11, and 24, which showed superior germination performance, are recommended for future breeding programs. Furthermore, clustering enables the selection of parental lines with greater genetic distance (e.g., tolerant genotype 3 and sensitive genotype 5) for hybridization, facilitating the genetic analysis of drought tolerance mechanisms and supporting trait improvement efforts.
Highlights:
- Rapid, cost-effective PEG screening replaces field selection
- Root length as a reliable indicator of seed vigor
- Identifying 4 superior Nigella genotypes for drought tolerance
