نشریه علوم و فناوری بذر ایران
سال دوازدهم شماره 1 (پیاپی 29، بهار 1402)

This research was conducted in order to investigate the effect of aqueous extract of different organs of harmel (Peganum harmala) on the growth and germination of Amaranthus retroflexus and Chenopodium album in two experiments (laboratory and greenhouse) respectively, based on CRD with three replications and RCBD with four replications. The treatments included aqueous harmel extracts in concentrations of 10% and 20% root, 10% and 20% Aerial organ and control. with increasing extract concentration, the growth traits and total chlorophyll of both plants decreased significantly. The highest and lowest levels of inhibition rates were associated with 20% stem extract and 10% root extract, respectively, but total soluble sugars and antioxidant activity of weeds increased with increasing levels of harmel root and stem extract. shoot extract decreased the germination speed in Chenopodium and Amaranthus by 87.35% and 91.22%, respectively, compared to the control. In Amaranthus the length index of the plant by 63.33% and 96.67% respectively. the highest root and shoot concentrations (20%) decreased. The length of root by 50.49 and 86.94%, In Amaranthus and 47.87 and 81.80% in Chenopodium compared to the control. The highest total soluble sugar was observed at the level of 20% of the stem, and Amaranthus had more total soluble sugar with an increase of 64.9% compared to the control. Most traits in Amaranthus were more sensitive to the allelopathic effects of harmel compared to Chenopodium. extract of shoot was stronger than the root extract, which can be used in the preparation of herbicides with natural sources.

This study was conducted as a factorial experiments based on a completely randomized design with two factors cultivars (Modena and Okapi), aging level (0, 24 and 72 hours at temperature of 40˚c and relative humidity of saturated) and four replications to evaluate germination rate and percentage (GP), vigor index (SV), electrical conductivity (EC), catalase (CAT), ascorbate peroxides (APX), glutathione reductase (GR) and S-nitrosothiol (SNO) at the Ferdowsi University of Mashhad, 2019-20. Accelerated Aging (AA) treatments made significant decline in germination indices and biochemical characteristics (except EC) of canola seeds. Also, Modena cultivar was stronger in germination traits while Okapi cultivar was better in biochemical activities, which can be explained by difference in the primary genetic of the cultivars. According to the results, in the treatments of 72 hours of AA compared to the control, GP has decreased by 86%, CAT 88%, APX 89% and SNOs 36%. On the top of that, there was a positive correlation between SNOs and enzymes. In conclusion, Nitric oxide (NO) is likely to indirectly affect the antioxidant enzymes by SNOs in aged canola seeds. Seed aging targets the cell physiology by reducing the activities of antioxidant enzymes and NO and therefore increasing the rate of cell mortality.

Environmental stresses, including drought and salinity stress can play an important role in reducing plant growth and yield especially in the seedling establishment stage in arid and semi-arid climates of Iran.Therefore, identification of range plants tolerance to drought and salt is very important.To assay the effect of different concentrations of drought and salinity on germination and early growth of camelthorn(Alhagi maurorum) two experiments were performed separately in a completely randomized design with three replications in the laboratory of Bardsir Faculty of Agriculture, Shahid Bahonar University of Kerman.30 uniform seeds were sterilized with 10% sodium hypochlorite solution for 30 seconds and after washing the seeds three times with distilled water, they were placed in 9 cm Petri dishes on Whatman No. 2 filter paper.In the first experiment, polyethylene glycol solution (PEG6000) with concentrations of -1, -1.5 and -2 MPa was applied to obtain the osmotic potential, and in the second experiment, NaCl with concentrations of 100, 150 and 200 mM was used.Distilled water was also applied to make zero stress(control)in both experiments. Results showed that camelthorn seeds were able to germinate at -2 MPa of drought potential and 200 mM salinity potential.However, increasing drought and salinity stress significantly reduced germination percentage and rate, seed vigor index, seedling dry weight, shoot length, root length, shoot dry weight and root dry weight.Assessing the response of this plant to different levels of drought and salinity in the germination stage and early growth of seedling is important for forage production, soil protection and medicinal value

TIn order to evaluate the effect of iron nanooxide synthesized from oregano on germination, growth and biochemical characteristics of corn seedlings, an experiment was carried out in a randomized complete block design with three replications. Experimental factors included synthesized iron oxide nanoparticles and the application methods of iron oxide nanoparticles. The results showed that iron oxide nanoparticles had a significant effect on germination, growth, and biochemical characteristics of seedlings. The highest germination rate, vigor index, seedling dry weight, and length were achieved with the application of 240 mg L-1 of iron oxide nanoparticles. Among the nanoparticle application methods, seed priming compared to the method of adding them to the planting medium had a greater effect on improving germination, growth, and increasing the vigor index. Using 240 mg L-1 of iron oxide nanoparticles as priming resulted in the highest germination percentage, germination synchrony index, mean daily germination, and the lowest MGT. In the case of adding nanoparticles to the planting medium, although it had less effect than the priming method, adding 360 mg L-1 of iron oxide nanoparticles to the planting medium also caused a significant increase in corn germination. The use of different concentrations of iron oxide nanoparticles in both methods of nanoparticle application caused a significant increase in the activity of antioxidant enzymes in seedlings. Therefore, the use of a concentration of 240 mg L-1 of iron oxide nanoparticles as a priming can be suggested to improve germination, growth, and biochemical characteristics of seedlings.

Ferula assa-foetida is one of the important medicinal plants of Apiaceae that has been exposed to extinction with repeated withdrawals from its natural habitat. Study of seed germination behavior of this species can lead to the development of cultivation and protection of its natural habitat. In order to optimal conditions determine for the standard germination test of Ferula assa-foetida seeds (which belongs to the heights of Yasuj city located in Kohgiluyeh and boyer-ahmad provinces), this experiment was designed as factorial in a completely randomized design in six treatments with different levels, with control treatment and in three replications. The experiment was carried out in 2021-2022 in the seed quality analysis laboratory of the Seed and Plant Registration and Certification Research Institute of Karaj, this factorial experiment was conducted based on a completely randomized design. For this purpose, Ferula assa-foetida seeds were evaluated under different temperature regimes (including 10, 15, and 20 °C) and different germination substrates (top of the paper (TP), between paper (BP), and sand (S)). Various pretreatments in the standard germination test process include stratification (for 14 and 35 days at 7 °C) and treatment with different substances (including gibberellic acid, kinetin, and potassium nitrate) as well as the seeds leaching for 24 hours. According to the results, kinetin pre-treatment (250 ppm) and TP seed germination substrate at 10 °C; optimal germination conditions of Ferula assa-foetida seeds were proposed for evaluation of different seed samples.

Suitable germination and crops establishment are one of the most significant and fundamental issues that overshadow the economic performance of the product. Improving the quality of seeds by relying on their pre-treatment is one of the issues that can be considered. Accordingly, the present study was performed to investigate the effect of pretreatment of sugar beet seeds using humic in factorial experiment in 2017. The first factor was humic acid including four levels of zero, 8.33, 12.50, and 25.00 mg per 100 g of seed, and the second factor, cultivar included two levels of Ekbatan and Paya. According to the results of the analysis of variance, the main effects of humic acid and cultivar had a significant effect on all evaluated characteristics except root dry weight at one and five percent probability levels. Humic acid-cultivar interaction was significant only for the three characteristics of mean germination time, root dry weight, and shoot dry weight. Based on the mean comparison results, the seed vigor (87.87%), germination rate (6.27 bud/day), seedling vigor length index (3.52) and seedling vigor weight index (1269.96) were assigned to seed pretreatment using 12.50 mg of humic acid per 100 grams of seeds. Seed pretreatment without significant difference in the amount of coating material increased the uniformity of seed germination. Among the two studied cultivars, the Ekbatan cultivar was superior to the Paya cultivar in terms of all studied characteristics. In general, the use of humic acid improved the germination characteristics and early growth of seedlings.