Plant Stress
Masoomeh Amerian; Gholamreza Gohari; Saeid Jalali-Honarmand; Sima Panahirad; Georgia Ntatsi
Abstract
Purpose: Salinity stress is one of the most important limiting factors affecting all plant processes, from seed germination to seedling development and plant growth. Seed priming is the most promising seed technique which quickens the germination process and enhances stand establishment. Therefore, seed ...
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Purpose: Salinity stress is one of the most important limiting factors affecting all plant processes, from seed germination to seedling development and plant growth. Seed priming is the most promising seed technique which quickens the germination process and enhances stand establishment. Therefore, seed priming with allantoin and serotonin was performed to investigate their effects on germination and growth of bitter melon seeds under salt. Research method: The experiment was conducted as a factorial experiment in a completely randomized design with three replications. The first factor consisted of three concentrations of salinity (0, 50 and 100 mM NaCl) and the second factor included seed priming (48 h) with modulators: control (distilled water), allantoin (1000 μM), serotonin (100 µM) and allantoin + serotonin. After 48 h of applying the priming treatments, the seeds were dried and placed in 9 cm diameter petri dishes lined with filter paper, moistened with the prepared salt solutions, and allowed to germinate at 25 °C. Germination percentage, seed vigor and selected growth characteristics including length, fresh and dry weight of seedling, shoot and root of bitter melon were evaluated. Findings: The results revealed that seed germination and seedling growth of bitter melon decreased in line with increasing salt concentrations: on the other hand, seed priming with allantoin (1000 μM) and serotonin (100 µM) alleviated this negative effect of salt stress. It was concluded that allantoin and serotonin, as seed priming agents, positively influenced bitter melon germination under salt stress. These findings may also be applicable to other plants and probably the observed stress tolerance might occur throughout the plant growth period. Research limitations: No limitations were identified. Originality/Value: Given the medicinal value of bitter melon, solving its germination problem, especially under salt stress conditions, will be of great help to those interested in cultivating this plant.
Ornamental Plants
Maryam Davoudi; Hassan Bayat
Abstract
Purpose: Seed germination and seedling growth are recognized as the most sensitive stages of salinity for the majority of plant species. This experiment aimed to characterize the impact of various salinity levels on selected ornamental plants from the Asteraceae family including Gazannia splendens, Rudbeckia ...
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Purpose: Seed germination and seedling growth are recognized as the most sensitive stages of salinity for the majority of plant species. This experiment aimed to characterize the impact of various salinity levels on selected ornamental plants from the Asteraceae family including Gazannia splendens, Rudbeckia hirta, Ageratum houstonianum, Gaillardia aristata, and Coreopsis grandiflora during the seed germination stage. Research method: Five independent experiments were conducted in a completely randomized design (CRD), comprising seven treatments with different concentrations of sodium chloride (0, 20, 40, 60, 80, 100, and 120 mM) in four replications using Petrie plates. Findings: The salinity of 120 mM significantly reduced the seed germination percentage in G. splendens, G. aristata, and C. grandiflora, compared to the other species. A. houstanianum exhibited a stimulating effect on seed germination percentage with salinity levels ranging from 20 mM to 80 mM. Salinity stress at a concentration of 120 mM had negatively affected vegetative traits in A. houstonianum, R. hirta, G. aristata, and C. grandiflora, inhibiting the growth of plumule in A. houstonianum and C. grandiflora. However, traits like plumule length and seedling length in G. splendens remained unaffected by salinity. Research limitations: No limitations were identified. Originality/Value: Results demonstrate varied responses of ornamental plants to different salinity levels. R. hirta exhibited superior performance in seed germination and early seedling stages compared to other plants.
