نشریه علوم و فناوری بذر ایران
سال یازدهم شماره 4 (پیاپی 28، زمستان 1401)

In this research, Sesame (Sesamum indicum L var.shevin) seed germination characteristics under drought stress conditions influenced by different seed priming treatments were investigated. In two separate experiments, germination responses to different temperatures (1, 5, 10, 15, 20, 25, 30, 35 and 40 ° C) and also different drought stresses (water potentials of -9, -11, -13 and -15 bar) were considered. Based on the results, 25 ° C was determined as optimum germination temperature. The -11 bar water potential was also determined as drought stress. Hydropriming and osmopriming of the seeds were performed at three temperatures of 20, 25 and 30 ° C. The duration of priming was determined based on the priming temperature and type. Calcium chloride osmopriming treatment was performed in three concentrations of 1, 2 and 3 mM. The seeds were primed using potassium nitrate in three concentrations of 0.1, 0.2 and 0.3%. After priming using the mentioned treatments, the seeds were dried out to initial seed moisture content and then subjected to drought stress (-11 bar) during germination period to determine the best priming treatments. Priming treatments significantly improved seed germination characteristics under drought stress. Overall, The results of this experiment demonstrated that use of hydropriming for the seeds of sesame had the highest germination features. So this treatment can be presented as an appropriate treatment for this plant as it is cost-effective, safe and eco-friendly.

Seed germination is one of the most important and basic stages of plant growth and development so it has great importance and effect on other stages of its growth. Cassia is a plant from the legume family and has many medicinal properties. Cassia propagation is done by seeds, but no study and report on the tolerance of these seeds to salinity stress in the country have been presented yet. Two factorial experiments were performed in a completely randomized design at the Seed Technology Laboratory of Agricultural Sciences and Natural Resources University of Khuzestan. In the first experiment, the effect of hormone priming treatment with gibberellin, halopriming with potassium nitrate, and hydro priming on Cassia seed germination was investigated. The results of this experiment showed that the highest seed vigor was obtained in the treatment of 50 mg/l gibberellin for 12 hours of priming. After selecting the best treatment (gibberellin 50 mg/l for 12 hours), germination characteristics of primed seeds compared with no primed seeds under salinity stress (0, 4, 8, 14, 16, and 20 dS/m). The results showed that seed tolerance to salinity stress at the germination stage increased significantly with seed priming. The highest seed vigor was observed in priming treatment at no salinity stress condition (339.89) while the lowest seed vigor of primed treatment was observed in 20 dS/m. Unprimed seeds could not withstand salinity stress beyond 4 dS/m.

In order to investigate the effect of humic acid, iron and silicon nanoparticles on quantitative and qualitative yield and filling components of wheat seed under salinity conditions, a factorial layout was carried out based on a randomized complete block design with three replications in the research greenhouse of University of Mohaghegh Ardabili during 2021. Treatments included salinity levels (without salinity as a control, salinity of 35 and 70 mM by NaCl and without salinity as a control), foliar application of nanoparticles at four levels (no foliar application as a control, foliar application of 0.8 per liter of nano iron, 40 mg / l nanosilicon spraying, combined application of iron nanoparticles and silicon nanoparticles and no foliar application as a control) and humic acid spraying (spraying with water as a control and spraying 3 g/l. The results showed that combined application of humic acid and foliar application of 40 mg of iron and nanosilicon nanoparticles in the absence of salinity, increased maximum seed weight, seed filling rate, length and effective seed filling period, Spike length, 100-seed weight, plant height, number of seeds per spike, chlorophyll index (56.60, 1.183, 39, 58.45, 58.5, 39.53, 2.51, 70.6, and 57.57 respectively) and increased the yield of single plant (46.97%) compared to the conditions of non-application of humic acid and nano-oxides under the salinity of 70 mm of soil. Nanooxides (iron and silicon) can increase wheat seed yield of wheat under salinity stress conditions by improving seed filling components.

Considering the environmental problems due to the usage of chemical herbicides, to control the weeds we can increase soil temperature by mulching. This research was conducted in Fasa in 2020. The experiment was performed as a factorial in a completely randomized design with three replications.The first factor was four varieties of weeds including Amaranthus retroflexus, Chenopodium album, Portulaca oleracea and Plantago lancoelata and the second factor was duration of mulching cover in 3 treatments including control, 20 and 40 days. After the periods of plastic mulching, the seeds were taken out of the soil depth and were examined based on standardized germination test. The results showed that the percentage and rate germination seeds, vigor and alpha and beta amylase decreased with the plastic mulching was used. 40 days of plastic mulching caused a reduction in germination speed comparing to the treatment which had no plastic mulching. By increasing the duration of the usage of mulching, the electric conduction of seeds showed an increase applying plastic mulching for forty days caused a decrease in seedling growth comparing to the treatment. The highest decrease in germination and seed vigor among the weeds was observed in Chenopodium album on the other hand plastic mulching treatment couldn't affect the germination in Plantago lancoelata. Overall, the results of this study showed that the parameters related to seed germination in different weed species was different based on the time of sun exposure under plastic mulch; So that solarization for 40 days is recommended to control weeds.

in this study, the effect of silver nanoparticles and humic acid on some morphological characteristics of quinoa seedlings under drought stress was investigated. The experiment was performed as a factorial experiment in a completely randomized design with three replications. The experiment consisted of three levels of silver nanoparticles (0, 10 and 20 mg L-1 AgNPs), three levels of humic acid (0, 100 and 300 mg L-1) and three levels of drought stress (0, -6 and -12 bar). In this study, Titicaca cultivar was used. The highest amount of seed vigor and seed germination rate were observed in the highest level of AgNPs and humic acid, which indicates the positive effect of AgNPs and humic acid on germination percentage, germination rate and quinoa seed vigor. According to the obtained results, drought stress led to a decrease in germination percentage and growth characteristics of quinoa seeds. AgNPs and humic acid had a positive effect on germination and growth characteristics of quinoa seedlings under drought stress conditions compared to control treatment. With increasing the concentration of AgNPs and humic acid, the amount of proline, soluble sugars, total phenol, flavonoids and catalase activity under drought stress increased, indicating the positive role of AgNPs and humic acid to increase drought tolerance in quinoa. Therefore, the use of humic acid at a concentration of 300 mg L-1 along with 20 mg L-1 AgNPs is recommended to improve germination and seed growth of quinoa under drought stress conditions

In the national standard for canola seed production, wild mustard is considered an illegal weed. Although canola and wild mustard can be distinguished by the morphological traits, it is not possible to distinguish the seeds of two species, especially the coated seeds. The present study was conducted to optimize the identification and detection of wild mustard seeds in rapeseed lots by morphological, chemical and molecular methods. The other seed count test was performed according to the rules of international seed test in rapeseed sampling. Chemical test design was performed under KOH treatment. The results of the chemical test were presented in five different status. Three specific markers of DA, DC and 5S rDNA were used, respectively. The Cruc marker is thought to be an internal control. Multiple polymerase chain reaction show amplification patterns of wild-mustard seed-specific markers with 5S rDNA amplified 190 bp that did not amplify in canola seeds. DA and DC markers in canola seeds amplified 239 and 625 bp, respectively, which did not amplify in wild mustard. According to molecular specific Profile and comparison with different status of rapeseed. Morphological limitation features and similarity of expression states of seed-related traits in wild mustard and rapeseed and factors such as seed coverage and chemical treatment restriction of wild mustard from rapeseed masses according International seed testing will not be possible, in which case DNA-based molecular tools will provide reliable results.