نشریه علوم و فناوری بذر ایران
سال چهارم شماره 1 (پیاپی 7، بهار و تابستان 1394)

To study the effects of drought stress and nitrogen fertilizer levels on some seed quality indices of two red kidney bean genotypes, a field experiment was carried out as a split factorial arranged in a randomized complete blocks design with three replications. The main plots were three drought stress levels [irrigation after 60 (without stress), 90 (mild stress) and 120 (severe stress) mm evaporation from open pan class A] and factorial combinations of N fertilizer at four levels (0, 50, 100, and150 kg N ha-1) and two red bean genotypes (Akhtar and D81083) were assigned in sub-plots. The seeds were evaluated by standard germination test and electrical conductivity (EC) test after harvesting at full ripeness. These experiments were carried out as factorial based on a completely randomized design. Results showed that drought stress decreased normal seedling percentage, root length, shoot length, root weight, shoot weight, and seedling vigor index. Also, application of nitrogen fertilizer increased EC value, root length, shoot length and seedling length vigor index. Generally, germination indices of D81083 in non-stress conditions were better than Akhtar but, there was not significant difference between two genotypes in terms of severe drought stress level

In order to evaluate the priming effects of gibberllic acid and potassium nitrate on germination and seedling growth characteristics of three populations Satureja sahendica،, an experiment was conducted. The treatments including plant populations (Majarition, Zeninjab and Osko), gibberllic acid (500, 250 ppm) and potasium nitrate (1%, 2%) and cold treatment in three replications arranged in factorial was carried out in greenhouse and laboratory conditions in Natural Gene Bank Group of Research Institute of Rangeland and Forestry in 2011- 2012. After seedling growth, traits including: percentage and speed of germination, root and shoot length , ratio of root length by shoot length, vigor index, normal seedlings, seedling length, fresh and dry weight and ratio of dry weight to fresh weight were measured in laboratory condition. Also in greenhouse, traits including: percentage and speed of emergence, root and shoot length , ratio of root length by shoot length, normal seedlings, seedling length, fresh and dry weight and ratio of dry weight to fresh weight were measured. Analysis of variance showed that there were significanc differences between populations, treatments and interaction of populations with treatments(5%) for all traits in both experimental conditions except for seed emergence percentage and shoot length in greenhouse condition. Comparing seed germination characteristics of three population showed that population of Mjarishen selected from East Azarbijan had higher vigor characteristics like seed germination (97%), speed of germination (15 sprout/day) and vigor index(41) than other populations in laboratory condition. In greenhouse condition, percentage and speed of emergence of Osko population as 17% and 1 sprout/day, respectively, were higher than other two populations. Effect of treatment on the populations showed that priming of the seeds with gibberllic acid were more effective for vigor traits like(germination speed, emergence speed and vigor index) than the other treatments in both experimental conditions.

In order to investigate the effects of increasing soluble phosphorus (P) on seed production and quality of black seed (Nigellasativa L.) in a calcareous soil, a field experiment was conducted at Faculty of Agriculture, Ferdowsi University of Mashhad, Iran, in 2013. Field experiment was conducted as factorial layout based on a complete randomized block design with four replications. The fertilizer resources (vermicimpost (V) + Tiobacilus (T), Sulfur (S) + T, V+S+T and control) and three levels of P (0, 30 and 60 kg.ha-1) were the first and second experimental factors, respectively. Seed vigor was also assessed by radicle emergence (RE) test for further evaluation of the effects of P on mother plant on the quality of producing seeds. A germination percentage at day 4 was used as seed vigor test. The resources of soil amendment (V+T, S+T and V+S+T) significantly decreased the P concentration in coat, P percentage of coat to seed and mean germination time. For instance, by applying V+S+T, P concentration in coat and mean germination time were decreased by 18 and 10%, as compared to control treatment.However, 1000 seed weight, seed vigor, P concentration in embryo and seed were significantly increased by applying the resources of soil amendment. There was a significant negative relationship between 1000 seed weight and P concentration in coat (R2= 0.66 **). It seems that under P-deficient conditions in soil, mother plant prefer to produce more longevity seeds, instead to increase theseed vigor, by increasing the P allocation to seed coat

In order to study of salinity effects on seed germination and seedling growth of milk thistle and thistle, an experiment was carried out. Experiment was factorial based on a completely randomized design with three replications. Treatments included seeds of wild species milk thistle and thistle and five salinity levels (0, 50, 100, 150 and 200 mM NaCl). Results showed that salinity leads to decrease in germination percentage, germination rate and increase in mean germination time that these changes were more in thistle compared to milk thistle. Seedling growth indices (length and fresh and dry weight of cotyledon and hypocotyl) were also affected by salinity. Most traits of thistle were not affected by salinity (50 mM) in comparison with milk thistle, whereas these changes were higher in levels of salinity and this result indicated more relative tolerance to salinity in thistle. However, salinity caused to decline primary and secondary vigor and seed reserve use efficiency, but seed reserve using rate decreased under stress condition. The amount of Na+, K+ and Ca2+ in radicle increased in low levels of salinity and decreased by enhancing of stress intensity.

In order to investigate the effect of temperature on the mobilization of protein reserves of wheat cultivars and seedling traits a factorial experiment conducted based on a completely randomized design at seed technology laboratory of  the Faculty of Agricultural sciences, University of Mohaghegh Ardabili with three replications. Treatments were three germination temperatures including 10, 20 and 30 ◦C and three wheat cultivars (Sardari, Finikan and MV17). Studied traits included germination percentage and rate, seedling dry weight, protease activity and protein content, respiration index and distribution of dry matter to seedling parts. Results showed that the highest germination percentage, rate and mean of germination time were related to 20 ◦C in all cultivars. The highest protein contentin in seed residual (8.7%) was observed in Sardari cultivar at 10 ◦C,but the lowest activity of protease (4.63 unit mg-1) was related to Finikan at this temperature. The highest amount of seed material lost as respiration (20.21) attained in MV17 cultivar at 30◦C. The highest seed reserves mobilization efficiency was related to Finikan and MV17 (1.23 and 1.2 respectively) at 20◦C. Seed dry matter distribution to radicle and plumule was different in cultivars and temperatures and the highest distribution to radicle (6.27%) and plumule (15.84%) were related to MV17 and Finikan cultivars, respectively at 20 ◦C. Seed protein reserves remobilization efficiency was the same in all cultivars at 20 ◦C, but MV17 at 10 ◦C and Finikan at 30 ◦C had the highest efficiency. In conclusion, higher germination percentage of MV17 at 20 ◦C can be related to the higher activity of protease

The assessment of medicinal plants tolerance is very important for cultivation of them in saline areas. Salicylic acid is a growth regulator which its role was investigated in plants tolerance to environmental stresses such as salinity.In order to evaluate the effects of salicylic acid on early seed germination andseedling growth of black cumin (Nigella sativa) under salt stress, an experimentwas conducted in a factorial arrangement based on a completely randomized design with 15 treatments and three replications. The experimental treatments were including different concentrations of salicylic acid (0, 0.25, 0.5, 0.75 and 1 mM) and salinity (0, 50 and 100 mM). The seeds of black cumin which were primed with different concentrations of salicylic acid for 24 hour, for germination test under salt stress, they transferred into sterile petri dishes which contain 10 ml NaCl. Results revealed a significant reduction in germination percentage and rate, seedling dry weight, seed vigor index, radicle length, radicle fresh and dry weight, shoot length, shoot fresh and dry weight with increasing salinity stress. Pretreatment with salicylic acid caused an increase of plant tolerance to salinity stress.  The application of salicylic acid greatly caused the increment of germination percentage and rateand enhanced fresh and dry weight of black cumin under salt stress. It seems that higher concentrations of salicylic acid (0.5 up to 1 mM) caused an increase of all mentioned traits under normal and stress conditions.

To study the influence of different priming methods (hardening, hydrothermal, hydro priming, KCl2, CaNO3, NaCl, KNO3 and control) and duration of priming (3 and 6 h) on seedling characteristics and germinationindices of Althaea Officinalis L. seeds, two laboratory and pot experiments carried out separately factorial arrangements based on a completely randomized design in the Agricultural faculty of Urmia University. Analysis of variance showedthat there were significant differences between priming methods, durations of priming and their interactions in respect of all traits. The seed priming methods as compared with control improved seedling and germination indices by 3 to 8 fold.On the other hand, it was confirmed that all of germination parameters improved along with increasing the duration of priming. Finally, it was found that CaNO3 priming for 3 and 6 hours had the mostpositive effects on the seedling and germination indices. Therefore, this priming can be used to prepare Althaea Officinalis seeds for planting.

This experiment was conducted as split factorial in a Randomized Complete Block Design (RCBD) with three replications in the research farm of Shahrekord University during 2010-2011 growing season. In this experiment irrigation treatments in three levels of: non water stress (irrigation after 50 mm evaporation from class A pan), moderate and sever water stress (irrigation after 70 and 90 mm evaporation from class A pan, respectively) were used as main factor, while factorial combination of Zn (spraying with pure water, spraying of 100 and 200 g Zn per hectare) and Mn (spraying with pure water, spraying of 150 and 300 g Mn per hectare) were used as sub-factor. The results showed that drought stress did not have any significant effect on germination rate, mean germination time, seedling length and dry weight while significant increases were obtained on germination percentage, coefficient of velocity of germination and seed vigor indices (I and II). Moreover, Mn foliar application in amount of 150 g per hectare had the highest germination percentage, germination rate, coefficient of velocity of germination,vigor indices (I and II) and the lowest mean germination time. The highest germination rate, seedling length and dry weight and vigor indices (I and II) was obtained for 100 g Zn per hectare

This experiment was conducted to study the effect of salinity and drought stress on germination and growth characteristics of wild mustard seedlings collected from irrigated wheat fields on the base of a complete randomized design in Iranian Plant Protection Research Institute. Different levels of salinity and drought stress included of 0 (control), -2, -4, -6, -8 and -10 bar were created by NaCl and poly-ethylene-glycol (PEG), respectively. Measured criteria included of final germination percentage, germination speed, seedling length, plumule length, radicle length and seedling vigor index. According to the results, mentioned stresses had negative significant effect on germination rate and percentage, length of plumule, radicle and seedling and seedling vigor index. More significant effect in drought stress than salinity stress showed higher resistance of wild mustard in salinity stress rather than drought stress. Both salinity and drought stress affected length of plumule more than length of radical. It means that length of plumule is more sensitive to mentioned stresses. According to fitted model, X50 (the potential caused to 50% reduction of final germination and germination rate of wild mustard) related to salinity stress (7.33 and 5.03, respectively) was significantly higher than X50 related to drought stress (4.47 and 2.90, respectively).

Proper nutrition of mother plant plays an important role in the production of seeds with high vigor. Therefore, a factorial experiment was done in a completely randomized design with 12 treatments and 3 replications to study the germination characteristics of cumin seeds which harvested from mother plants treated with different amounts of vermicompost and mycorrhiza fertilizers, in the Faculty of Agriculture, Yasouj University, Iran, in 2013. Vermicompost treatments consisted of three levels (0, 5 and 10 tons per hectare), and mycorrhiza fungi consisted of 4 levels (control, inoculation with Glomusmossae, inoculation with Glomusintraradices and inoculation with both species). For most of the germination traits, as well as seed nitrogen and phosphorus content, the effects of vermicompost and mycorrhiza were significant.  Results showed that the highest radicle length (2.57 cm), plumule length (1.61 cm) and vigor index (3.069) of the seeds was achieved by application of 10 ton vermicompost with G. mosseae, the highest seed nitrogen and phosphorus content observedin the application of 10 tons of vermicompost plus inoculation with two fungi, the largest seedling length was observed in application of 10 ton/ha vermicompost without mycorrhiza, the highest germination rate in the treatment of application 5 ton vermicompost without mycorrhiza and the highest germination percentage were obtainedin treatment of 5 tons vermicompost and G. mosseaeOverall, the results of this experiment showed that application of vermicompost and mycorrhiza especially combined treatment of 10  ton/ha verrmicompost plus G. mosseae and G.intraradices could increase uptake of nutritional elements such as nitrogen and phosphorous to seeds and  therefore enhance germination performance in cumin seeds.