نشریه تحقیقات بذر
پیاپی 47 (تابستان 1402)

In a laboratory study, the effect of seed nutritional pretreatment on germination and seedling growth traits of lentil (Lens culinaris Med.) in the form of two separate experiments in the form of a completely randomized design with three replications for two pretreatment materials [prime with iron sulfate (FeSO4) and zinc sulfate (ZnSO4) ] were investigated. In each experiment and for each prime material, five levels of prime material concentration (30, 60, 90, 120 and 150 mM) were considered. The measured traits were germination percentage and speed, length of root and shoot, wet and dry weight of seedling, and longitudinal root index of seedling. The results of the data showed that in terms of the type of pretreatment, iron sulfate was superior to zinc sulfate and caused the major improvement of the germination indicators, except for the germination speed. Also, by increasing the concentration from 30 to 60 mM, the highest indicators of germination and seedling growth were obtained. However, with a further increase in the concentration of the pre-treatment material, a decreasing trend was observed in all the measured traits, which could possibly be due to the toxicity in the seeds under high concentrations of metals. In general, according to the obtained results, it seems that the use of these two substances, especially iron sulfate, with a maximum concentration of 60 mM, is beneficial for improving the germination and nutritional characteristics of seeds.

Several studies reported that drought stress in the soil, by reducing the germination indicators, causes a decrease in onion growth and yield. Ascophyum nodosum seaweed extract contains plant growth regulators such as auxin and cytokinin, high and low consumption nutrients, vitamins and antioxidants and can reduce various stresses on plants. For this purpose, different levels of seaweed extract and drought stress were investigated on the germination and growth indices of onion (Behbahan native cultivar). A factorial experiment was performed based on completely randomized design with 3 replications. The investigated factors include: algae extract at 4 levels (0, 3, 6, and 9 percent by volume) and drought stress at four levels non-stress, mild stress, moderate stress, and severe stress (including 0, -0.3, and 0.6 and -0.9 MPa). Drought stress was applied by PEG. The results of this research showed that in conditions non-drought stress, mild stress and moderate stress, the use of Ascophyllum nodosum algae extract (levels of 3% and 6%) caused a significant increase in traits such as germination percentage, germination vigor, seed vigor index, seedling length, plumule length and radicle length. In severe stress conditions, no significant difference was observed between the control levels, 3% and 6%. Considering the development of onion cultivation in Behbahan and the report of negative effects caused by drought stress on onion seeds (Behbahan native cultivar), the use of Ascophyllum nodosum seaweed extract in the soil is recommended to reduce the negative effects caused by drought stress. Algae extract improved the germination indicators, growth characteristics and proper establishment of seedlings , which can increase the yield of this plant.

In order to investigate the effect of different concentrations of KNO3 on physiological and biochemical properties of maize (Zea mays L.) under salinity stress a factorial experiment was conducted based on completely randomized design at the University of Mohaghegh Ardabili in 2021. Treatments included three salinity levels (0, 100 and 200 Mm) and three KNO3 levels (0, 1.5 and 3%). The results showed that the highest germination percentage (GP), germination rate (GR), germination uniformity (GU), radicle and plumule length (RL and PL) and radicle fresh and dry weight (RFW and RDW) was related to priming with KNO3 3% and without salinity. Mean of germination time (MGT) compared to the control showed a reduction about 53%. The activity of catalase, peroxidase and superoxide dismutase enzymes in priming with KNO3 3% and 200 mM salinity compared to the control showed an increase about 56, 68 and 67%, respectively. Salinity decreased the activity of amylase, but priming with KNO3 increased the activity of this enzyme. The total seed protein content in KNO3 3% pretreatment and without salinity was increased about 63%. In general, priming with KNO3 3% solution can be considered as the best treatment to improve the physiological and biochemical properties of corn under salinity stress.

This study aims to investigate the effect of priming treatments (control without priming, hydropriming, priming with 0.25% potassium nitrate and priming with 0.5% potassium nitrate) on the germination characteristics of sugar beet cultivars and growth characteristics under five levels of salinity (0, 4, 8, 12, and 16 dS/m) on germination and seedling growth in four replicates in a petri dish in laboratory conditions as a factorial experiment based on a completely randomized design. The results showed that the effect of seed priming and salinity stress on the average germination time, germination speed coefficient, germination variance, germination uniformity, root length, stem length, stem and root dry weight, water content relatively, chlorophyll a, chlorophyll b and carotenoids were significant. The results showed that in all three genotypes, the number of germinated seeds decreased with the increase in salinity level, and in the control levels and the use of water as a priming factor, this decrease was moderated. With the increase of salt concentration up to 12 ds level, the relative water content increased sigmoidally and showed a relatively stable trend at two levels of 12 and 16 ds. In most of the investigated traits, Shokofa variety has shown less reaction than other genotypes. In the investigation of the reaction process of genotypes to the speed, variance and homogeneity of germination in prime and salinity levels, it has shown a decrease with increasing salinity concentration.

This research was carried out to investigate the effect of seed storage temperature and moisture content on germination characteristics, growth and biochemical characteristics of Borago officinalis seedlings, In factorial arrangement in a completely randomized design with 4 replications. The treatments included five levels of seed moisture (5, 10, 15, 20, 25%) and eight temperature levels (10, 15, 20, 25, 30, 35, 40 and 45 degrees Celsius) and 12 storage levels (7, 14, 21, 28, 35, 42, 49, 56, 63, 70, 77 and 84 day). The results showed that with increase in storage time, percentage and seed germination rate, length decreased, and also the abnormal seedlings, amount of proline seedlings and activity of peroxidase enzymes were increased. The highest germination and seedling growth were obtained in the control treatment and 7 days after storage with 10% seed moisture after 7 days of storage. The lowest germination percentage was seen 84 days after storage with %15 seed moisture at 15°C. The maximum length of seedlings was obtained at 25°C temperature and 20% humidity with 7 days of storage. The results showed that at the temperature of 25 degrees, the peroxidase enzyme activity was the highest at the beginning of the storage period (28 days of storage), but with the continued influence of adverse conditions during storage, the enzyme activity decreased significantly. The results showed that the lowest amount of proline was obtained at a temperature of 15°C with a humidity level of 25% and at the 28th day of storage. Based on the results, with increasing storage time, the moisture content of seeds and the storage temperature of the quality of Borago officinalis seedlings are reduced. Since these seeds contain oil, it should be considered to be sufficient to store, survive and maintain its maximum quality.

One of the most important techniques for improving the quality and quantity of seedlings is the use of seed treatment with PGPR, which can increase the plant's resistance to adverse conditions. For this purpose, the effect of seed inoculation of Cerasus mahaleb in 10 forest provenances of Fereydunshahr city, Isfahan province with the most important rhizosphere bacteria that stimulate plant growth, on the components of seed germination in a factorial experiment in the form of a randomized complete block design It was done with three replications in the greenhouse, seed inoculation with five levels including no bacterial inoculation (as a control), inoculation with (Bacillus sp.), (Azotobacter sp.), (Pseudomonas fluorescens) and a combination treatment of three growth stimulating (MIX) and calculation of different components of Cerasus mahaleb seed germination was done. The results showed that mixed inoculation treatment (MIX) had the greatest effect on the indicators of germination speed (0.039 per day), seed germination (39.20), germination strength (20.38 percent) and The root length was (8.66 mm) compared to other treatments. P. fluorescens bacteria treatment also showed the best performance in germination percentage index (17.55%) and stem length (8.76 mm). On the other hand, the weakest performance among the bacterial treatments was related to the growth promoting bacteria (Bacillus sp.). Among the 10 areas of Cerasus mahaleb seed collection, Chal Khalil 1 and 2 forest reserve areas as well as Peshtkoh Som Durak 2 showed better seed germination indicators than other areas. In general, seed inoculation with PGPR can be a suitable solution for producing healthy and strong seedlings, better establishment, and also increasing the success of planting seedlings in disturbed and degraded habitats of Cerasus mahaleb in Zagros forests.