Radicle Dry Weight Research Articles

A Study of Effects of Different Organic Origin Liquid Seaweed Doses on Germination Radicle and Plumule Growth in Winter Cereal Species

In this study, it was aimed to determine the effects of liquid seaweed on seed germination and radicle and plumule growth in some winter cereal species (Triticale (T), Barley (B) and Wheat (W)) were investigated. In the study, 6 different doses (Control (D0), 1000 ppm L-1 (D1), 2000 ppm L-1 (D2), 4000 ppm L-1 (D3), 8000 ppm L-1 (D4) and 16000 ppm L-1 (D5)) of seaweed were used. Germination index (number day-1), radicle and plumule fresh weight (g), radicle and plumule dry weight (g) and germinated seed number (number) were measured during the 14-day development period of cereal species at all seaweed doses. According to the study findings, apart from "number of germinated seeds in cereal species" and "germination index in species x dose interaction"; significant differences were found between the average values of all the properties examined in the grain types, fertilizer doses and species x dose interactions. Wheat among cereals had the highest values with regard to radicle dry weight and radicle fresh weight. D2 dose from the doses of seaweed fertilizer form has the highest values in germinated seed number, radicle dry weight, plumule dry weight, and radicle fresh weight, while D5 dose was the lowest. In terms of species x dose interaction, radicle fresh weight was found to be high in T x D1 interaction. Germinated seed number and plumule fresh weight were found to be high in H x D0 interaction. Germinated seed number and radicle dry weight were found to be high in W x D2 interaction. As a result, in the germination study with liquid seaweed, D2 dose for wheat, D1 and D2 doses for triticale, D0, D1 and D2 doses for barley were found as encouraging.

Effect of Artemisia vulgaris L. Aqueous Extract on Some Germination Properties and Seedling Growth of Wheat

A laboratory experiment was carried out during the winter season of 2021 in the Seed Technology Laboratory - College of Agricultural Engineering Sciences / University of Baghdad to find out the allopathic effects of aerobic and terrestrial aqueous extracts of artemisia on the seed germination and seedling growth of wheat. A factorial experiment according to a completely randomized design (C.R.D.)at three replicates was used; the first factor included the type of aqueous extract for plant parts, which were aerobic (stems and leaves) and terrestrial (root and rhizomes), while the second factor included five concentrations for each aqueous extract of plant part (0, 25, 50, 75 and 100%). The results showed a significant effect of aqueous extract types on the studied traits; the terrestrial aqueous extract gave the highest germination percentage (70.00%) and radicle dry weight (0.0487 g). Also, the concentration of 50% of artemisia aqueous extract was significantly superior and achieved the highest germination percentage (80.00%) and shoot dry weight (0.0500 g). In contrast, the concentration of 25% was significantly superior in the shoot length (7.47 cm) and radicle dry weight (0.0567 g), while the concentration of 75% was significantly superior in the radicle length (4.17 cm). The interaction between the two factors significantly affected the radicle length and dry weight only. Keywords: Artemisia, weed, allopathic effects, phenolic compound

Early Test of the Tolerance of Upland Rice to Drought in the Germination Phase

Climate change in the form of drought will reduce agricultural production, so it is necessary to develop superior drought-tolerant varieties. The study aimed to determine the drought-tolerant local upland rice cultivars at the germination stage. From September to December 2021, the study was carried out at the Seed Science and Technology Laboratory, Faculty of Agriculture, Tadulako University, Palu, Center Sulawesi, Indonesia. A completely random design (CRD) with a two-factor factorial pattern was employed in the study. Twelve cultivars comprised the first factor, while two superior drought-resistant variants served as comparators. The second factor is osmotic stress, namely P0 = control, P1 = -1 bar, P2 = -2 bar, and P3 = -3 bar, so there are 56 treatment combinations repeated four times, so there are 224 experimental units. The observed variables were maximum growth potential, germination rate, radicle length, plumule length, radicle dry weight, plumule dry weight, sprout dry weight, water volume, and germination rate. The results showed that drought stress through PEG – 1 bar did not affect germination. Using PEG down to -3 bar resulted in a significant reduction in germination. Pulut ko, logi and sina ponding are cultivars that have tolerance to drought stress.

تأثير المستخلص المائي للشيح المعمر في خصائص الانبات ونمو البادرة للكتان

A laboratory experiment was carried out during winter season of 2021 in the Seed Technology Laboratory- College of Agricultural Engineering Sciences/ University of Baghdad, to find out the allopathic effects of aerobic and terrestrial aqueous extracts of Artemisia vulgaris L. on the seed germination and seedling growth of linseed. A factorial experiment according to a completely randomized design (CRD)at three replicates was used; the first factor in clouded type of aqueous extract for two plant parts which were aerobic (stems and leaves) and terrestrial (root and rhizomes), while the second factor included five concentrations of each aqueous extract of plant part 0, 25, 50, 75 and 100%. The results showed that there was significant effect of aqueous extract types on the studied traits; the terrestrial aqueous extract gave the highest germination percentage 64.67% and germination speed 25.37%/d, whereas the aerobic aqueous extract gave a highest mean of radicle length 2.5936 cm. Regarding of aqueous extract concentrations of Artemisia vulgaris weed, the concentration of 25% of Artemisia aqueous extract was significantly superior and achieved the highest mean of germination speed 27.25 %/day, shoot length 3.98 cm, radicle dry weight 0.0043 g and shoot dry weight 0.0239 g, while the control treatment 0% was significantly superior in the germination percentage 100% and radicle length 2.6615 cm. The interaction between two factors had significant effect on the germination percentage and germination speed only.

Wheat seed deterioration stimulated by plant extracts

During 2019-2020, the experiment was conducted in the laboratory of the Department of Field Crop Sciences, Faculty of Agricultural Engineering Sciences - Baghdad University, to investigate the impact of soaking wheat seeds produced during the 2016 agricultural season with three plant extracts (licorice root extract 2%, 4% and 6%, Acadian and Humic(500, 1000, & 1500 mg L-1). Aside from the two control treatments (soaking in distilled water with dried seeds). The results show that the soaking treatment with licorice root extract outperformed the other therapies in conventional laboratory germination, root length, and seedling vigor index (95 percent and 3.42 cm 1207) compared to the two control treatments (soaking with distilled water and dry seeds). While all the Humic and Acadian soaking treatments at the concentrations (500 and 1000) mg L-1 did not significantly differ with the distilled water soaking treatment.The characteristics of standard laboratory germination percentage, root length, coleoptile length and seedling vigor index. Thus, we conclude that soaking wheat seeds with high concentrations of Acadian (more than 1000 mg L-1) leads to a deterioration in the vitality of the seeds. While soaking with licorice root extract enhances the vibrancy and activity of wheat seeds compared to the other extracts used. As a result, we propose soaking the somewhat old and low-vital wheat seeds in a concentration of at least 2% licorice root extract. Keywords: Radicle dry weight, Seedling vigor, seed germination, seed storage.

Effect of the physical mutagenesis with 60Co on jalapeño pepper seed quality

Physical mutagenesis with 60Co is a technique used in plant breeding to induce desired phenotypic characteristics. This research objective was to evaluate physical and physiological quality and protein content of jalapeño pepper (Capsicum annuum L.) seeds from plants that were selected as tolerant to water stress, these plants were derived from seeds irradiated with 60Co at 100 Gy dose (T1P2 and T1P5 both from tolerant plants to water stress). Control seeds were significantly superior to the mutants in the variable standard germination (90.66%), standard germination with accelerated aging (57.3%), normal seedlings (95.6%), 1000 seeds weight (6.349 g), hectoliter weight (51.97 kg hL-1) and radicle dry weight (18 mg). Mutant seeds were significantly superior to control seeds in seed length and width (4.356 mm in T1P2 and 4.256 mm in T1P5 for length; 3.544 mm in T1P2 and 3.632 mm in T1P5 for width). In seed thickness tests, germinated seeds aerial part fresh and dry weight, radicle fresh weight, the two mutants seed types and the control were significantly equal. In seed storage proteins content, T1P2 treatment had a higher globulins concentration. In the prolamin fraction, the two mutant seed types were superior to control. T1P5 treatment seeds had the highest glutelins concentration. Mutant seeds showed different characteristics as compared to control in physical, physiological and plantlet parts weight components.

Response of Fenugreek (Trigonella foenum-graecum L.) Genotypes for their Germination and early Seedling Parameters Grown Under Different Saline levels

Seedling establishment is a most critical stage that determined the crop production at later stages. An in vitro investigation was carried out at the Laboratory of the Department of Plant Breeding and Genetics, Sri Karan Narendra College of Agriculture, Jobner (Rajasthan) in Rabi season 2016-17 to study the response of fenugreek genotypes for their germination and early seedling parameters under five salt stress levels viz. 0.0 mM, 40 mM, 80 mM, 120 mM and 160 mM. Fifteen seeds of each genotype were sown in sterilized Petridish and seedling observations were recorded. Results revealed that the average value was found maximum in the control and minimum at higher salinity level for most of traits. Higher reduction was found at higher salinity levels for most of the characters viz., plumule length, radicle length, seedling length, plumule to radicle length ratio, plumule fresh weight, radicle fresh weight, plumule dry weight, radicle dry weight and seedling vigour index but germination percentage showed less reduction. The contrast between mean of various genotypes in control conditions (S0) versus Sm (mean of S1, S2, S3 and S4) for each character also showed that overall mean was highest in control as compared to the overall mean of salinity levels for all the traits. This investigation concluded that higher level of salinity (above 60 mM) adversely most affected to seed germination and other early seeding traits rather than (below 40 mM) lower salinity levels. Based upon the rank totals of genotype over different salinity levels S1, S2, S3 and S4 (Sm) and characters, the RMt-303 was found to be most desirable genotype followed by UM-385, RMt-143 and RMt-305. These lines would be used as a viable option under saline conditions and better exploit in hybridization programme.

Allelopathic Effect of Lamiaceae Plant Extracts on Seed Germination and Seedling Related Traits of Two linseed (Linum usitatissimum L.) Varieties

      A laboratory experiment was conducted during the 2017- 2018 growing season under laboratory conditions in the Biotechnology Laboratory/ Department of Biotechnology and Crop Science / College of Agricultural Engineering Sciences / University of Sulaimani/ Iraq. This factorial experiment conducted in a Randomized Complete Design with three replications. The first factor was two tested Linseed varieties (Local and Poland). The Second factor was aboveground biomass of three Lamiaceae plant species Spearmint (Mentha spicata), Peppermint (Mentha piperita) and Basil (Ocimum basilicum) The third factor was two kinds of dried (Spearmint, Peppermint and Basil) plant extracts methods (Aqueous and Alcoholic extraction). The fourth factor was three concentrations (1:1, 1:2 and 1:3) with control. Various germination attribute characters Germination Percentage (G%), Inhibition (-) /Stimulation (+) of Germination, Mean Germination Time (MGT), %, Coefficient Velocity of Germination (CVG), Germination Rate Index (GRI), Radicle Length (cm), Plumule Length (cm), Radicle Dry Weight (g), Plumule Dry Weight (g) were studied. From the results it was observed that Poland variety super passed Local variety in most of germination attribute characters, plant source Ocimum basilicum however had a higher allelopathic effect on inhibition of G% which lead to longer day of germination but gave higher plumule length and dry weight. Alcoholic extraction methods had a great effect on inhibition of G% which lead to longer germination time but gave higher CVG and plumule dry weight. (1:1) concentration gave higher inhibition of G% which leaded to longer days for germination while control gave maximum value for the rest of germination attribute characters. The obtained results from the interactions between all factors were various the most effective character was inhibition of G% which gave maximum values for each interactions between Poland variety and Ocimum basilicum, local variety and alcoholic extraction, Poland variety and (1:1) concentration, Ocimum basilicum and alcoholic extraction methods, Ocimum basilicum and (1:1) concentration, alcoholic extraction methods and (1:1) concentration, Local variety, Ocimum basilicum and alcoholic extraction methods, Local variety, Ocimum basilicum and (1:1) concentration, Ocimum basilicum, aqueous extraction and (1:1) concentration and Poland variety, Mentha piperita, alcoholic extraction and(1:1) concentration.

Hormopriming instigates defense mechanisms in Thyme (Thymus vulgaris L.) seeds under cadmium stress

Seed germination and root development are vital phases of the plant growth process; however, these steps are strongly influenced by the seed characteristics and environmental conditions. Seed priming provides a condition for uniform and rapid germination and plant establishment. Limited studies are available on the effect of seed priming to ameliorate cadmium (Cd) stress in thyme plants. Hence, the effect of seed hormopriming (salicylic acid and jasmonic acid, 100 mg.l−1) was evaluated. Hydropriming was done using double distilled water. Seed priming significantly increased the seed germination percentage (GP) and germination rate (GR) at all stress levels of Cd contamination. SA-primed seed showed the greatest increase in GP and GR at 30 mg.l−1 Cd by 26 and 37 %, respectively, compared with the control. Salicylic acid (SA) increased plumule and radicle length 29 and 43 %, respectively, at 30 mg.l−1 of Cd concentration compared with the control seeds. SA pretreatment increased plumule dry weight more than radicle dry weight. The leaf antioxidant enzyme activity was increased with increasing Cd concentration. Seed priming with SA increased superoxide dismutase (SOD) and peroxidase (POX) activity by 14 and 15 %, respectively. Leaf malondialdehyde (MDA) content was increased 15 % at 30 mg.l−1 Cd concentration compared with the control plants, but SA priming reduced leaf MDA content 18 % compared with the control seeds. The greatest leaf proline content was observed at 30 mg.l−1 Cd concentration and SA priming. Regardless of the priming treatment, the greatest leaf protein content was observed at 10 mg.l−1 Cd concentration compared with the control. Seed priming with SA diminished the adverse effects of Cd on germination process via enhancing the antioxidant activities and accumulation of osmolytes. Therefore, hormopriming of thyme seeds by SA can enhance the resistance of this valuable medicinal herb to cadmium stress.

Effect of different methyl jasmonate concentrations on pumpkin (Cucurbita pepo L.) seedling tolerance to chilling stress

اگرچه کشت زودهنگام محصولات بهاره برای استفاده از شرایط معتدل بهاری و همچنین رشد رویشی مناسب اهمیت زیادی دارد ولی وجود دماهای پایین در ابتدای دوره رشد ممکن است رشد گیاه را با تنش سرما مواجه نماید. این آزمایش به‌صورت فاکتوریل شامل شش غلظت متیل جاسمونات (صفر، 1، 5، 50، 100 و 150 میکرومولار) و سه سطح دما (8، 11 و 14 درجه سانتی­گراد) در قالب طرح کاملا تصادفی در شرایط کنترل‌شده در دانشگاه شهرکرد در سال 1395 اجرا شد. در روز یازدهم صفات مورفولوژیکی و بیوشیمیایی اندازه‎گیری شد. نتایج نشان داد که بیشترین طول ریشه‎چه در غلظت 50 میکرومولار متیل جاسمونات و دمای 11 درجه سانتی­گراد با 55.6 درصد افزایش نسبت به شاهد حاصل شد. در دمای 8، 11 و 14 درجه سانتی‌گراد بذرهایی که با متیل جاسمونات تیمار نشده بودند فاقد ساقه‎چه بودند. در دمای هشت درجه سانتی­گراد، غلظت پنج میکرو مولار بیشترین طول ریشه ­چه، طول ساقه­ چه و وزن خشک ساقه­ چه را داشت. در بین تیمارهای متیل جاسمونات، بیشترین میزان فعالیت آنزیم‎های گایاکول پراکسیداز و کاتالاز نیز در غلظت پنج میکرومولار مشاهده شد. در دمای 11 درجه سانتی­گراد، غلظت پنج میکرومولار به علت افزایش طول ساقه­ چه، وزن خشک ریشه­ چه، میزان فعالیت آنزیم کاتالاز نسبت به سایر غلظت‎ها برتری داشت و ازلحاظ طول ریشه ­چه و فعالیت آنزیم سوپر اکسید دیسموتاز در رتبه دوم قرار گرفت. در دمای 14 درجه سانتی­گراد، غلظت 50 میکرومولار دارای بیشترین وزن خشک ریشه­ چه، وزن خشک ساقه­ چه و میزان فعالیت آنزیم­ های سوپراکسیددیسموتاز، گایاکول پراکسیداز و کاتالاز بود. در دمای 14 درجه سانتی­گراد، بیشترین میزان طول ساقه ­چه و شاخص بنیه بذر در پنج میکرومولار مشاهده شد و از این لحاظ غلظت 50 میکرومولار در رتبه دوم قرار گرفت. به‌طورکلی نتیجه‎گیری می‎شود که کاربرد متیل جاسمونات باعث افزایش فعالیت آنزیم‎های آنتی‌اکسیدان و درنتیجه تحمل گیاهچه کدوی پوست‌کاغذی به تنش دمای پایین می­شود.

Efficacy of polyethylene glycol (PEG) induced drought on germination indices and photosynthetic pigments of sweet corn var.NSC-901B

Germination of seed is considered as the first and most fundamental stage of a plant life cycle so that, the achievement in growth and yield production also depends on this stage. Drought stress is one of the most important environmental factors that limit the growth, development and production of plants. The influence of drought stress (0, -.6, -1.2 and -1.8 bar) by polyethylene glycol (PEG) 6000 on seed germination indices and photosynthetic pigments in sweet corn was examined under laboratory conditions with triplicates. Results indicated that drought stress significantly reduced germination per cent (76%), radicle length (71%), plumule length (65%), radicle fresh weight (76%), plumule fresh weight (68%), radicle dry weight (78%), plumule dry weight (56%), chlorophyll a (67%), chlorophyll b (75%), total chlorophyll (69%) and carotenoids (72%). Overall, drought stress had a negative effect on all the parameters.

Sarcopoterium spinosum (L.) Spach aqueous extract inhibits seed germination and seedling growth of winter wheat (Triticum durum Desf.)

Aqueous extract of Sarcopoterium spinosum (L.) Spach was evaluated for phytotoxicity effect against winter wheat (Triticum durum) seed germination and seedling growth. Aqueous concentrations of 2, 4, 8 and 10% (w/v) of Sarcopoterium spinosum were used. The reduction in germination percentage was more than 40%, while the reduction in germination rate was almost 60%. The reduction in radicle length was more than 60%, while the reduction in radicle dry weight was almost 50%. The reduction in plumule length was more than 40%, while the reduction in plumule dry weight was more than 35%. The reduction of root dry weight was more than 60%, while the reduction of shoot dry weight was more than 35%. The reduction of chlorophyll content was more than 40% at the highest extract concentration compared with control. In conclusion, S. spinosum had strong phytotoxicity effect against winter wheat. Therefore, S. spinosum aqueous extract is a good candidate as a bio-herbicide against winter wheat.

Seed germination of dill (Anethum graveolens L.) in response to salicylic acid and halopriming under cadmium stress.

Seed priming is a technique which is potentially able to promote rapid and more uniform seed germination and plant growth as well. In this regards, the presowing effects of seed priming treatments were investigated on some physiological viz. seed germination, germination rate, radicle elongation, shoot elongation, radicle dry weight, shoot dry weight and vigor index. Seeds were subjected to two seed priming methods, hormopriming, and halopriming. Also, untreated seeds were used as control. Halopriming with -0.5 MPa of KNO3 and KCl and hormopriming with 100 mg/L of SA at 15 ˚C were used for 24 h in a factorial experiment with completely randomized design under laboratory conditions. The results showed that hormopriming (100 mg/L of SA) improved the germination rate (no significant difference with KNo3 and KCl), germination percentage, radicle elongation, plumule elongation, radicle dry weight, plumule dry weight, and vigor index under cadmium stress (30 mg/L) at 56.35, 11.9, 30.65, 30.33, 65.21, 71.42, and 46.16%, respectively. In all cadmium concentrations, the maximum of all germination parameters were related to the seeds primed with SA solution. While in primed seed by KNO3 and KCl treatments, exposure to 20 and 30 mg/L Cd decreased radicle length as compared to the control. Also, exposure to 30 mg/L Cd, KNO3 solution showed lower plumule length than control. The amount of reduction in radicle length in primed seeds with KNO3 solution and KCl solution was 11.88% and 6.18%, respectively, in 30 mg/L Cd. However, in all cadmium concentrations, germination percentage and rate were enhanced by KNO3 and KCl solubles.

Germination response of grasspea (Lathyrus sativus L.) and arugula (Eruca sativa L.) to osmotic and salinity stresses

AbstractThe use of genetic potential of forgotten plants such as grasspea and arugula is an appropriate strategy for increasing of plants tolerance to environmental stresses. Therefore, in this laboratory study the effects of different levels of osmotic (0, -2, -4, -6, -8, -10, -12 and -14 bar caused by PEG) and salinity (0, 50, 100, 150, 200, 250, 300 and 350 mmol induced by NaCl) stresses were evaluated on germination indices of grasspea and arugula in four separate experiments. Arugula showed a suitable tolerance to osmotic stress, so that its germination percentage and rate at treatment of -10 bar were similar to control. Arugula had 79% germination at osmotic level of -14 bar, but its germination rate at this level was 60% lower than control. In addition, its radicle length until -8 bar and radicle dry weight up to -14 bar were higher than control treatment. However, all levels of salinity stress particularly treatments of more than 100-150 mmol decreased the germination indices of arugula. Germination percentage of arugula in 150 and 200 mmol treatments was 22 and 56% lower than control treatment, respectively. Grasspea had partially suitable tolerance to osmotic stress until -6 bar, but then intensified the reducing trends of its germination indices and finally reached to zero at -14 bar treatment. Moreover, salinity stress especially treatments of higher than 100 mmol decreased all germination indices of grasspea. Overall, arugula was a more tolerant plant especially to osmotic stress; therefore this forgotten plant can be used in agronomic and breeding programs in areas affected by drought stress.

The effect of NaCl salinity and temperature on the germination of three thyme populations

A factorial experiment was performed in completely randomized design (CRD) with three replications to evaluate the effect of different densities of sodium chloride on germination traits of thyme plant seeds collected from three different habitats. The first factor was three different habitats, the second factor was different salinity levels (0, 50, 100, 150, 200 and 250 mM) and the third factor was different temperatures (15, 25, and 35°C). Analysis of variance showed that the effect of habitat was not significant on seeds germination characteristics. But temperature had a significant effect (P≤0.05) on germination percentage, germination speed, seed vigor, plumule length, radicle dry weight and plumule dry weight. Moreover, salinity had significant effects (P≤0.01) on germination percentage, germination speed, plumule length, seed vigor and ratio of plumule length / radicle length, plumule weight, and radicle dry weight. The maximum germination speed (1.02), germination percentage (45.4%), sees vigor (1.69), radicle length (3.99 mm), plumule length (2.66 mm), radicle dry weight (0.131 mg) and plumule dry weight (0.197 mg) was obtained in 15°C. Also, the maximum percentage of germination (69.5%), germination speed (1.34) and the radicle length (5.5 mm) was obtained from control treatment (without salinity stress).

Allelopathic Potential of Aerial and Root Extracts of Alfalfa Against Germination and Seedling Related Traits of Four Weed Species.

In this study, we investigated the effect of aerial and root water extract of Alfalfa
 (Medicago sativa) plant on seed germination and seedling growth of four weed species. This
 study was carried out in the phytochemistry laboratory/Faculty of Agricultural Sciences/Sulaimani
 University. Factorial experiment conducted in Completely Randomized Design (CRD) with 3
 replications, including five concentrations 2,4,6,8 and 10 g of aerial and root dry tissues of alfalfa
 (Medicago sativa L.) plants per 100ml of MeOH 70% v/v, against germination and seedling growth
 of four problematic weeds, which widely distributed in wheat fields, namely cephalaria (Cephalaria
 syriaca L.), rye grass (Lolium perenne L.), bitter vetch (Lathyrus linifolius L.) and black mustard
 (Brassica nigra L.). Results of experiment showed that extracts from dry tissue of aerial and root
 parts of alfalfa greatly inhibited seed germination and seedling growth of weeds at all
 concentrations compared to water control. Root extracts had the higher allelopathic potential
 toward imbibitions and germination of weeds compared to aerial extracts. Root extract reduced
 imbibitions by 61, 54, 61, 54 % and caused germination inhibition I%, by 51, 37, 34, and 47 % in
 cephalaria, rye grass, bitter vetch and black mustard respectively. Aerial extracts, significantly
 reduced hypocotyls, radicle length and dry weight compared to root extracts. The reduction of
 seedling traits of cephalaria, rye grass, bitter vetch and black mustard respectively due to aerial
 extracts compared to water control were 52, 52, 32, 35% hypocotyls length reduction, 41, 44, 33,
 48% radicle length reduced, 58, 61, 64, 76% hypocotyls dry weight losses and 60, 57, 58, 77% were
 losses in radicle dry weight. Allelopathicity increased for aerial and root tissues with increase in
 concentrations and the greatest inhibition was 80% equally for imbibitions and I%, which obtained
 by 10g dry root tissue per 100 ml MeOH extract occurred in cephalaria, while 10 g dry aerial tissues
 per 100 ml MeOH extracts shows the highest inhibition percentages of hypocotyls length by 78% in
 rye grass, radicle length by 79% in cephalaria, hypocotyls dry weight and radicle dry weight by
 90% both in black mustard.

Ascorbic Acid and It′S Effects on Alleviation of Salt Stress in Sunflower

Salinity, a severe environmental factor, has limited the growth and productivity of crops. Many compounds have been applied to minimize the harmful effects of salt stress on plant growth. A laboratory experiment was carried out to assess the effects of seed priming with ascorbic acid (ASA) on germination characteristics of sunflower ( Helianthus annuusL.). The seeds were treated with different concentrations of ASA (0, 1 and 2 mM) before germination, then theprimed seeds were germinated under salinity stress conditions using different concentrations of NaCl (0, 100 and 200 mM). Some germination characteristics including germination percentage, germination rate, seed stamina index, hypocotyl dry weight, radicledry weight, relative water content and ion leakage were measured after imposing salinity stress for 8 days. Salinity stress caused a significant reduction in germination and seedling growth of sunflower. Seeds primed with various concentrations of ascorbic acid proved to be effective in salinity tolerance at the germination stage of sunflower. In general, priming with 2 mM ascorbic acid was more effective than the other concentrations.

The Effects of Source of Priming and Post-priming Storage Duration on Seed Germination and Seedling Growth Characteristics in Wheat (Triticum aestivem L.)

This study was designed to investigate the effects of seed storing after priming on germination of two wheat cultivars (Cross Alborz and Sardari). The study consisted of five experiments. In experiments 1- 4 we tested seed priming with distilled water (hydro priming), potassium nitrate (KNO3), gibberellin (GA3), PEG-6000 (osmopriming) in different concentrations (50, 100 150 and 200 ppm for GA3) and (1%, 2%, 3% and 4% for KNO3) and times (12, 18, 24 and 30 hours). Germination tests were subsequently performed on all above mentioned seed priming methods. The best treatment (time and concentration of media) which emanated from experiments 1-4 was considered for experiment 5. In experiment 5, we tested the effects of storing duration after seed priming (0, 30, 45 and 60 days) on germination characteristics of wheat. Maximum stem and radicle length, stem and radicle dry weight and speed of germination in cv. Cross Alborz and cv. Sardari were observed in priming treatments when the seeds primed by GA3 50 ppm for 24h, KNO3 1% for 24h, hydropriming 12h and osmopriming 12h.The results showed that storing of primed seeds improved shoot and radicle length, shoot and radicle dry weight, germination percentage and speed of germination.