This research was conducted for evaluation of germination treatments and favorite planting date of three medicinal plant species including Dorema (Dorema ammoniacum), Asafetida (Ferula assa-foetida) and Galbanum (Ferula gummosa) in Agricultural College of Ferdowsi University of Mashhad in 2008. Effect of different levels of temperature and washing on germination percent and rate of species were evaluated in first experiment. Temperature in 6 levels including 1, 4, 7, 10, 13 and 20 °C and seeds treatment in 3 levels including drench, washing and extract were surveyed. In the second experiment, emergence condition of species in four planting dates including first December, first January, first April and first May in pot and out door conditions were evaluated. Result showed that, optimum temperature for germination of Dorema, Asafetida and Galbanum plants were 7.83, 8.27 and 3.14 °C, respectively. Further, germination percent of each plant had a positive and significant relation

In order to study the effect of foliar application of zinc and iron on germination of soybaen seed under different level of irrigation, an experiment was conducted in 2009 at Shahrekord agricultural research center. Main factor was including of four levels of drought stress as irrigation (irrigation after 60, 80, 100 and 120 mm evaporation from class A evaporation basin) and sub factor was including of four levels of foliar applications (water, zinc sulfate, iron sulfate and combined of zinc and iron sulfate). Results showed that seed yield, seed zinc content, germination percent and rate and mean germination time and seedling and cotyledon dry weight were affected by the interaction of irrigation and foliar application. Irrigation after more eveporation significantly decreased 1000-seed weight. Foliar application of ironand combined of zinc and iron had significant effect on seed iron content. Germination percent in irrigation after 80 and 120 mm evaporation from the class A evaporation basin was not affected by foliar application, and iron foliar application in other levels of irrigation, let to the lowest germination percent. Foliar application of iron had the highest mean germination time. Foliar application of element. Root and shoot dry weight was increased by foliar application of zinc compared to water and combined of zinc and iron foliar application. Generally foliar application of zinc and combined zinc and iron, could improve most of the germination characteristics. High correlation coeficient between 1000-seed wieght and seed zinc content with most of the germination characteristics, showed that these traits had maximum effect on germination of soybean.

In order to study drought stress during flowering and seed maturity and normal irrigation effect on mother plant on some seed germination and seedling vigor related traits of 10 oilseed rape winter cultivars, an experiment was conducted as factorial, based on completely randomize design by four replications, during 2013 in experimental field of Seed and Plant Improvement Institute (SPII) and seed quality analysis laboratory of Seed and Plant Certification Research Institution(SPCRI) at Karaj. Experiment treatments were seeds produced under normal irrigation(S1) and drought stress exertion by non irrigation at flowering and maturity stage(S2) of 10 oilseed rape winter cultivars. One thousand weight, density and electrical conductivity of seeds measured and by standard germination test conduction, final germination percent, mean germination time, seedling length and dry weight were determined. Results indicated that mean germination time and seedling length were not affected by studied treatments and also final germination percent of studied cultivars had not significant difference. Highest thousand seed weight was related to Zarfam cultivar which seeds produced by normal irrigation treatment and Orient and SLM046 cultivars had highest seed density produced by normal irrigation treatment. Zarfam cultivar seeds produced by drought stress treatment had highest and Milena and Modena cultivars seeds produced by normal irrigation treatment had lowest electrical conductivity. Seeds produced by normal irrigation treatment had highest final germination percent. Highest seedling dry weight in normal irrigation condition belong to Geronimo and under drought stress condition related to Okapi cultivar. Generally, this experiment results showed that drought stress at flowering and maturity duration caused studied genotypes seed quality decrease, but under that conditions, Geronimo, Zarfam, Dexter and Licord cultivars had higher seed thousand weight, Orient, Modena and Dexter cultivars more seed density, Milena and Modena cultivars lower electrical conductivity and, Okapi and Modena cultivars higher seedling dry weight in comparison with other studied cultivars. Therefore can produce those cultivars having relatively optimum germination quality and seedling vigor traits seed.

In order to recognize effects of chemical and mechanical treatments on some of the most important features of seed germination of Myagrum, an experiment was conducted based on completely randomized design with four replications at Razi University. The experiment treatments were distilled water (control), sulfuric acid (98% for 2, 3 and 4 minutes), potassium nitrate (3%for 3, 4 and 7 days), hydrogen peroxide (30% for 2, 3 and 4 minutes) and scarification with sandpaper and prechilling (for 1, 2 and 3 weeks). Germination percent, germination rate, length and dry weight of epicotyl, length and dry weight of radicle, seedling total dry weight and vigor index were evaluated for Myagrum seed. Results showed that the most germination percent was related to hydrogen peroxide treatment for3 minutes (91 %) and scarification with a chilling for 3 weeks (84 %) and the lowest germination percent was observed in sulfuric acid treatment. The results of treatment group comparisons also showed that using hydrogen peroxide had the greatest impact on seed germination of Myagrum. The most germination rate (4.5) and epicotyl dry weight (1.6 g) was observed in hydrogen peroxide for 3 minutes. The most epicotyl length (22.7 mm), radicle length (36.6 mm), radicle dry weight (1.1 g), seedling dry weight (2.5 gr) and vigor index (49.9) were related to seed scarification along with chilling for 3 weeks. Our results also indicted that application of sulfuric acid due to extreme damage onembryo leaded to death of Myagrum seed. It seems that lack of appropriate germination in Myagrum seed could be due to embryo physiological factors because all evaluated treatments had more impact on seed metabolic and harmonic processes.

Artemisia is the most important bush plants in natural plant communities. This plant i due to essential medicine and aromatic compounds have economic value. In this study, two experiments were conducted. In first experiment, genetic diversity 19 genotype of four species Artemisia were evaluated using 15 RAPD primers. Primers mplified 108 locus and produced a total 998 bands. Primer "F" has the highest genetic diversity index (0.58). Genetic similarity was calculated by employing Dice index and cluster analysis was carried out according Complete linkage algorithm that showed a similarity range (0.4-0.8).The highest similarity between the two samples A.sieberi (nodoshan) and A.khorassanica-678 (0.80). Cluster analysis, classified genotypes into 3 main groups at 0.46 coefficient of similarity. There was little relationship between genetic divergence and geographical origins. The results indicated the existence of genetic variation among Artemisia genotypes and high efficiency of RAPD markers in the expression of genetic variation between species and within species of Artemisia. In second experiment, the germination characteristics of five genotypes from two species were studied in salinity stress. A factorial experiment was conducted with two factor; salinity (0, 3, 6 and 9 dSm-1) and five genotypes .The germination percent, germination rate and mean of germination time were measured. The result showed that germination percent and germination rate were reduced by increasing salinity. Species A. sieberi (nodoshan) has the highest germination percent and was the most tolerant accession.

An experiment was carried out to evaluate the allelopathic potential of various concentrations of (0, 10, 20, 30, 40, 50, 60, 70, 80, 90 and 100%) of Atriplex canescens and Atriplex lentiformis which were prepared by aqueous suspension of 10% at the flowering stage on some germination traits (Root length, shoot length, seedling growth, germination percent, speed of germination, vigor index), physiological (total chlorophyll content) and biochemical (total phenols content) shoot let and leaflet of Agropyron elongatum as a non native plant which is introduced on range management projects of the eastern Golestan province in laboratory of Hydro-ecology at Gonbad-e-Kavous University. The experiment was conducted in a completely randomized design with three replications. The ANOVA analysis showed that species, various concentrations and the interaction of species and concentrations had significant difference at 1% on radicle length, speed of germination, seedling vigor index, total chlorophyll and total phenol content from shoot let and leaflet of A. elongatum. The interaction of species and concentrations on germination percent was significant at 5%. While the effect of them on shoot and seedling lengths were insignificant. The mean comparison of interactions effect of species and various concentrations indicated that there were significant decrease on total chlorophyll content and, radicle length, germination percent, speed of germination and seedling vigor index with increasing concentrations of two species of Atriplex as compared to control. On the other hand, the amount of total phenols of seedling had a rising trend with increasing concentrations trend over control. 100% of concentrations aqueous extract of A. canesence had a maximum of Phenols content (194/38%) as compared to control.

According to the effect of seed size on seed quality, this study was conducted in the Seed and Plant Certification and Registration Institute (SPCRI) in 2009-10, based on completely randomized design and with three replications. Studied factors(16 treatments) consisted of two canola cultivars (Okapi and Talaye), four separated seed sizes (1.4, 1.6, 1.8 and 2 mm) and two levels of using and none using of gravity separator tool. Based on the results using of 1.6 mm sieve size accompanied to gravity separator tool is recommended for cleaning these two varieties seed while germination percent and seedling emergence was improved and also higher seed loss percent was attained by using of sieves with 1.8 and 2 mm size. Whatever lower seed loss percent was attained using 1.4 mm sieve size but percentage of seed purity was decreased and also number of weed seeds increased which resulted in rejection at standard seed certification process. So the best treatment was related to the sieve with 1.6 mm size that was standard in the aspect of physical purity and germination percent.

This study was a randomized complete block experimental design with four treatments and four replications to determine the suitable furrows width for in-furrow grain drill and also wheat yield. Treatments were planting wheat by in-furrow grain drill with furrows width of 60, 75 and 100 cm and planting wheat on raised bed by conventional grain drill with furrow width of 60 cm (control). In this project, the effect of in-furrow grain drill on EC, seeds germination percent, 1000 seeds weight and crop yield were studied. Results indicated that in-furrow grain drill affected distribution of salinity (EC) in soil profile, seeds germination percent and wheat yield. The salt concentration at the top-center of beds and at the sides of the beds increased by 50.7% and 17.1% compare to mid-furrow, respectively. In-furrow grain drill with furrow width of 75 cm increased seeds germination (43.1%), 1000 seeds weight (5.9%) and crop yield (39.3%) compare to planting wheat on raised bed.

To study the effects of chilling on dormancy breaking and the increased germination characteristics of Nepeta (germination percent and speed, seedling length, vigor index, wet and dry weight), a factorial experiment in a completely randomized design with 4 replications was implemented in a laboratory in 2014. Factor A was the chilling treatment in three levels (control, one-month and two-month pre-chilling of wet seeds at 4°C) and factor B was related to the seeds of 10 different species of genus Nepeta. After chilling, seeds of control were placed in a germinator for 15 days at 20°C and light-to-dark cycle of 16 hours light (1000 lux) to 8 hours dark. The results showed that chilling treatments had significant effects (p<0.01) on germination percent, germination speed, vigor index and fresh weight, but they had no effects on the seedling length. The chilling effects on germination percent showed that one-month chilling had a positive effect on N. haussknechtii with 40% and N. menthoides with 36.5% and two-month chilling had a positive effect on N. haussknechtii with 43%. The two-month chilling effect on germination speed was positive for most species. Generally, one-month chilling had positive effects on the increased seed vigor index of N. betonicifolia, N. haussknechtii and N. menthoidesand by 20.48%, 25.33% and 17.99%, respectively as compared to that of control treatment and two-month chilling had positive effects on the increased fresh weight of N. cataria, N. haussknechtii, N. pungens, N. menthoides andN. crassifolia.

In order to evaluation of some seed germination and vigour indices of soybean commercial cultivars to seedling field emergence a laboratory and field experiment was conducted in seed and plant certification and registration institute at Karaj. Experiment conducted as factorial based on complete randomize design with12 treatments, 3 primary germinability, standard(80 percent), over standard(upper most germinability of each cultivar sample) and under standard(lowest germinability of each cultivar sample) of 4 soybean commercial cultivars, Williams and Sari(JK) procuced in Mazandaran province and Telar and 033 produced in Golestan province by 4 replication. Seedling length, seedling dry mater, normal seedling percent, abnormal seedling percent, final germination percent, mean germination time, coefficient of velocity of germination, mean daily germination, mean daily germination rate, seed length and weight vigour indices measured by standard germination test and seedling growth analysis test conduction. Also seeds planted in field and primary and final seedling emergence percent, seedling emergence rate and seedling cumulative emergence rate and seedling vigour index and seedling dry weight in field determined. Results revealed that seedling length and dry weight, coefficient of velocity of germination and seed length and weight indices and primary and final seedling emergence percent and seedling vigour index in field affected by cultivar × primary germinability interaction and other studied indices affected by any of factors. Also seedling length and dry weight, normal seedling percent, daily germination rate and seed length vigour index increasing in high germinability seeds observed and these seeds had high and primary and final seedling emergence percent and seedling emergence rate at field and strong vigour seedlings. Generally Williams and 033 cultivars with over standard primary germinability seeds for almost laboratory and field indices significantly higher than in comparison of other cultivars. In standard germination test normal seedling percent in comparison of final germination percent had high correlation with final seedling emergence in field. Thereafter, seem normal seedling percent determination could suitable criterion of potential vigour of seeds for seedlings establishment in field.