Seed priming to improve germination and seedling growth of ...

INTRODUCTION 

EurAsian Journal of BioSciences 

Eurasia J Biosci 6, 76-84 (2012) 

DOI:10.5053/ejobios.2012.6.0.9 

Seed priming to improve germination and seedling 

growth of safflower (Carthamus tinctorius) under 

salt stress 

Mohamed Aymen Elouaer*, Cherif Hannachi 

Department of Horticultural Sciences, High Institute of Agronomy, 4042 Chott-Mariem, Tunisia 

*Corresponding author: aymenouaer@gmail.com 

Abstract 

Background: Salinity affect germination and seedling growth of several crop species, many 

techniques are used to improve tolerance and development of plants. Priming is an effective 

technique that improves germination of several vegetables crop under saline condition. That’s why, 

this experiment was carried to study the effect of seed priming with 5 g/L NaCl and KCl on 

germination and seedlings growth of safflower (Carthamus tinctorius) exposed to five levels of 

salinity (0, 5, 10, 15 and 20 g/L). 

Materials and Methods: Safflower seeds were soaked in solutions of NaCl (5 g/L for 12 h) and KCl 

(5 g/L for 24 h) at 20°C. Primed and non primed seeds were put to germinate in petri dishes and 

irrigated with saline solutions of five concentrations of NaCl (0, 5, 10, 15 and 20 g/L). 

Results: NaCl and KCl priming have improved germination parameters (germination percentage, 

mean germination time, germination index and coefficient of velocity) and growth parameters 

(radicle and seedling length, seedling fresh and dry weight and Vigour Index) of safflower under 

saline condition. 

Conclusions: The present study revealed that, under salt stress, NaCl and KCl priming could be used 

as a method to improve safflower seed germination. However, further studies are needed to 

highlight effects of NaCl and KCl seed priming on future growth and development of the culture. 

Keywords: Carthamus tinctorius, germination, priming, salinity, seedling growth. 

Abbreviations: CV, Coefficient of Velocity; GI, Germination Index; MGT, Mean Germination Time; RL, Radicle 

Length; SDW, Seedling Dry Weight; SFW, Seedling Fresh Weight; SL, Seedling Length; TG, Total Germination; VI, 

Vigor Index. 

Elouaer MA, Hannachi C (2012) Seed priming to improve germination and seedling growth of 

safflower (Carthamus tinctorius) under salt stress. Eurasia J Biosci 6: 76-84. 

DOI:10.5053/ejobios.2012.6.0.9 

Salinity has an adverse effect on seed 

germination of several vegetables crops, by creating 

an osmotic potential outside the seed inhibiting the 

absorption of water, or by the toxic effect of Na + and 

Cl- (Khajeh-Hosseini et al. 2003). Osmotic and saline 

stresses are responsible of the inhibition and delay 

of germination and plant growth (Almansouri et al. 

2001). Water uptake during the imbibition’s phase 

decreases and salinity induces an excessive 

absorption of toxic ions in the seed (Murillo-Amador 

et al. 2002). Priming improves germination and 

emergence of several seed species (Singh 1995). This 

approach has proven it’s effectiveness to improve 

crop establishment on saline soil (Ashraf et al. 2001, 

Basra et al. 2005). Cayuela et al. (1996) working on 

tomatoes, Pill et al. (1991) working on asparagus and 

tomatoes, Passam and Kakouriotis (1994) working 

© EurAsian Journal of BioSciences 

on cucumber have concluded that priming improves 

seed germination and plant growth under saline 

condition. Sivritepe et al. (2003) have reported that 

NaCl seed priming of melon increases the 

emergence level and dry weight of plants under 

saline condition. Safflower is a moderately tolerant 

species to salinity (Maas 1986), however, it was 

reported that the crop is sensitive to salinity during 

germination phases affecting its growth and future 

development (François and Bernstein 1964). For this 

reason, this study attempt to investigate the 

germination behaviour of safflower seed and to 

highlight the effect of priming on germination and 

seedling growth under salt stress. 

Received: February 2012 

Accepted: July 2012 

Printed: August 2012 

76

EurAsian Journal of BioSciences 6: 76-84 (2012) 

Germination experiment was conducted in the 

laboratory of High Institute of Agriculture Chatt 

Mariem, Tunisia. Safflower seeds were primed with 5 

g/L NaCl and KCl solutions for 12 and 24 h 

respectively, at 20°C. After priming, seeds were 

washed with distilled water and than left to dry in air 

between two filter papers. Primed and non-primed 

seeds were placed in 9 cm petri dishes on a layer of 

filter paper (Whatman # 41). Twenty seeds were 

placed in each Petri dish. Petri dishes were irrigated 

with five different saline solutions consisted of 0, 5, 

10, 15 and 20 g/L concentrations of NaCl. The Petri 

dishes were placed in germinator at 20°C. The 

experiment was a factorial with two factors which 

are salinity at 5 levels (0, 5, 10, 15 and 20 g/L) and 

priming with 3 levels (non primed seeds (control), 

NaCl priming, KCl priming), arranged in a completely 

randomized design with five replications and 20 

seeds per replicate. Seed germination was recorded 

daily up to day 7 after the start of the experiment. A 

seed was considered germinated when the radicle 

emerged by about 2 mm in length. 

Parameters measured in this experiment were: 

• Total germination (TG) measured in the seventh 

day using the formula TG (%)= (total number of 

germinated seeds/ total seed) x 100. 

• Mean germination time (MGT) calculated 

according the formula of Ellis and Roberts (1981). 

MGT= ∑ (ni/di). With ni: number of germinated seeds 

and di: day of counting. 

• Germination index (GI) according to the 

equation of Kader and Jutzi (2004). GI= ∑(TiNi). Ti: 

number of day after sowing and Ni: number of 

germinated seeds in the day. 

• Coefficient of velocity (CV)= (number of 

germinated seeds per day) according to Kader and 

Jutzi (2004) formula. CV= (∑Ni /100) x (∑ Ti Ni). 

• Seedling length (SL) in (mm), Radicle length (RL) 

in (mm), Seedling fresh weight (SFW), Seedling dry 

weight (SDW). Seedling dry weight was determined 

after placing seedlings, after the 7th day, in oven to 

dry at 70°C for 48 h. 

• Vigour Index (VI) using the formula of Abdul- 

Baki and Anderson (1970). VI= [TG (%) x seedlings 

length (mm)]/100. 

77 

MATERIALS AND METHODS 

Elouaer and Hannachi 

All the data were subjected to an analysis of 

variance, using SPSS 13.0 software and the 

difference between means were compared by 

Duncan tests (P


Table 1. Analyses of variance of different parameters. 

*Significant at 0.05 according to Duncan test 

Table 2. Means comparison of the traits for primed and non-primed seeds of safflower. 

*Means with the same letters in each column are not significantly different at 0.05 according to Duncan test 

Table 3. Means comparison of the traits under different salinity levels. 

*Means with the same letters in each column are not significantly different at 0.05 according to Duncan test 

Results showed that salinity significantly (P


Fig. 1. Effect of different salinity levels on germination 

percentage (a) and mean germination time (b) of primed 

(NaCl and KCl) and non-primed (control) seeds of safflower. 

seeds, when exposed to salinity stress. 

Increasing salinity causes a significant decrease 

(P


Fig. 3. Effect of different salinity levels on seedling and 

radicle length of primed (NaCl and KCl) and non-primed 

(control) seeds of safflower. 

g/L to reach 0.84 g at 20 g/L (Table 2). However, primed 

seed showed the better performance than nonprimed 

seeds. Data in Table 3 shows that NaCl seed 

priming enhanced safflower seedling fresh and dry 

weight of about 83.38% and 71.42% respectively as 

compared to control (Fig. 4). This value was significantly 

higher for NaCl seed priming (2.09 g) and KCl 

seed priming (1.89 g) than control seeds (1.68 g). 

DISCUSSION 

The present study has investigated the effect of 

salinity and seed priming on germination and 

seedling growth of safflower. Data showed that 

salinity had significantly affected safflower 

germination. This study demonstrated that 

germination recorded from primed seeds were 

significantly different from un-primed seeds when 

exposed to different salinity levels. Similar findings 


Fig. 4. Effect of different salinity levels on seedling fresh 

and dry weight of primed (NaCl and KCl) and non-primed 

(control) seeds of safflower. 

were reported by Kaya et al. (2006). Primed seeds 

had better efficiency for water absorption from 

growing media, that’s why metabolic activities in 

seed during germination process commence much 

earlier than radicle and plumule appearance (Hopper 

et al. 1979). In general, increasing salinity causes a 

decrease in safflower germination; this may be due 

to the toxic effects of Na + and Cl - in the process of 

germination (Khajeh-Hosseini et al. 2003). It seems 

also that, salinity stress affects seed germination via 

the limitation of seed water absorption (Dodd and 

Donovan 1999), excessive use of nutrient pool 

(Bouaziz and Hicks 1990) and creation of disorders in 

protein synthesis. Mean germination time increased 

significantly with increasing salinity. NaCl and KCl 

primed safflower seeds germinated earlier than unprimed 

ones as it has been reported by Ashraf and 

Rauf (2001) working with other priming treatments, 

such as polyethylene glycol (PEG), inorganic salts or 

80


even ABA. According to Bewley and Black (1982), 

seed priming leads to the initiation of primary 

metabolic processes, so the time required for 

germination is reduced. This positive effect is 

probably due to the stimulatory effect of priming on 

later stages of the germination process through the 

mediation of cell division in germinated seeds 

(Sivritepe et al. 2003). Argerich and Bradford (1989) 

found that the swelling of the embryo inside primed 

tomato seed may speed up germination by 

facilitating water absorption. Indeed, the priming is 

an effective technique that increases seed vigor and 

improves germination and seedling growth 

(Jumsoon et al. 1996). Results found in our trial were 

consistent with the research work in this area. 

Several studies have shown that seed priming 

homogenized seed germination in a short period of 

time (Khajeh-Hosseini et al. 2003). The maximum 

coefficient of velocity of germination were found in 

the low salinity treatment and decreased with 

increasing salinity. Similar results were reported by 

Okcu et al. (2005). 

The findings of Ruan et al. (2002a) demonstrated 

that priming the rice seed with KCl and CaCl2 had 

improved results for germination index. Greater 

efficiency of seed priming with KCl is possibly 

related to the osmotic advantage that K + has in 

improving cell water saturation, and that they act as 

co-factors in the activities of numerous enzymes 

(Taiz and Zeiger 2002). 

In the present study, salt stress causes a 

significant reduction in seedling and radicle length, 

seedlings fresh and dry weight and vigor index. 

Reduction in seedling growth as a result of salt 

stress has been reported in several others species 

(Achakzai et al. 2010, Akram et al. 2010). Salinity has 

both osmotic and specific ionic effects on seedlings 

growth (Dioniso-Sese and Tobita 2000). Similarly, 

toxic ion accumulation (Na + and Cl - ) negatively affect 

plant metabolism (Grieve and Fujiyama 1987). It has 

also been reported that salinity suppresses the 

uptake of essential nutrients like P and K (Nasim et 

al. 2008), which could adversely affect seedlings 

growth. Cicek and Cakirlar (2002) have reported that 

salinity reduced shoot length, fresh and dry weight 

of maize seedlings. Result indicated that seed 

81 


priming significantly improved safflower seedling 

growth at different salinity level. Similarly, Katembe 

et al. (1998) investigated the effect of seed priming 

as a method to improve seedling growth of two 

Atriplex species under salt stress. Significant 

improvement in root and shoot length may be 

attributed to earlier germination induced by primed 

over un-primed seeds (Farooq et al. 2005), which 

resulted in vigorous seedlings with more root and 

shoot length than the seedlings from un-primed 

seeds. Our results confirm the findings of Stofella et 

al. (1992), who reported that priming of pepper 

seeds significantly improved radicle length. 

In our study, seedling fresh and dry weights 

decreased linearly with increasing salinity. The same 

results were also obtained by other researchers 

(Mansour et al. 2005). Increased seedling fresh and 

dry weight in primed seeds over the un-primed 

seeds were also observed by Sivritepe et al. (2003) 

who reported an increase in seedling dry weight in 

NaCl primed melons seeds under saline conditions as 

compared to the un-primed seeds. Seed priming 

improve significantly safflower vigor index under 

saline conditions. Similar results were found by Ruan 

et al. (2002b) who reported that primed rice seeds 

showed higher vigor index than non-primed ones. 

It is clear from these results that priming improves 

germination and growth of many crops. In this 

present study, safflower seed showed differential 

response to salinity and priming treatments. Reduction 

in germination parameters and seedling growth 

was more profound in control seeds than primed 

seeds. NaCl and KCl seed priming increase germination 

of safflower seeds. Thus, the priming may be an 

effective method to meet the demands of farmers 

during the installation of the culture in the field and 

especially in conditions of salt stress. For this reason, 

further studies are needed to assess the efficacity of 

seed priming during the later stages of the culture. 

ACKNOWLEDGEMENTS 

This work was supported by the High Institute of 

Agriculture, Chatt Mariem and Department of 

Horticultural sciences of the university; we wish to 

thanks all staff for their technical assistance.


REFERENCES 


Abdul-Baki AA, Anderson JD (1970) Viability and leaching of sugars from germinating barley. Crop Science 10: 31-34. 

Achakzai AK, Kayani SA, Hanif Z (2010) Effect of salinity on uptake of micronutrients in sunflower at early growth stage. 

Pakistan Journal of Botany 42: 129-139. 

Akram M, Ashraf MY, Ahmad R, Waraich EA, Iqbal J, Mohsan M (2010) Screening for salt tolerance in maize (Zea mays 

L.) hybrids at an early stage. Pakistan Journal of Botany 42: 141-151. 

Almansouri M, Kinet JM, Lutts S (2001) Effect of salt and osmotic stresses on germination in durum wheat (Triticum 

durum). Plant and Soil 231: 243-254. doi:10.1023/A:1010378409663 

Argerich CA, Bradford KJ (1989) The effects of priming and ageing on seed vigour in tomato. Journal of Experimental 

Botany 40: 599-607. doi:10.1093/jxb/40.5.599 

Ashraf M, Rauf H (2001) Inducing salt tolerance in maize (Zea mays) thorugh seed priming with chloride salts: Growth 

and ion transport at early growth stages. Acta Physiologiae Plantarum 23: 407-414. doi:10.1007/s11738-001-0050- 

9 

Ashraf M, Qureshi AS, Ghafoor A, Khan NA (2001) Genotype-environment interaction in wheat. Asian Journal of 

Biological Sciences 1: 356-367. 

Basra SMA, Afzal I, Rashid RA, Hameed A (2005) Inducing salt tolerance in wheat by seed vigor enhancement 

techniques. International Journal of Biotechnology and Biology 1: 173-179. 

Bewley JD, Black M (1982) Physiology and Biochemistry of Seeds in Relation to Germination. Vol. 2, Viability, Dormancy 

and Environmental Control, Springer-Verlag, Berlin. 

Bouaziz A, Hicks DR (1990) Consumption of wheat seed reserves during germination and early growth as affected by 

soil water potential. Plant and Soil 128: 161-165. doi:10.1007/BF00011105 

Cayuela E, Perez-Alfocea F, Caro M, Bolarin MC (1996) Priming of seeds with NaCl induces physiological changes in 

tomato plants grown under salt stress. Physiologia Plantarum 96:231-236. doi:10.1111/j.1399-3054.1996.tb00207.x 

Cicek N, Cakirlar H (2002) The effect of salinity on some physiological parameters in two maize cultivars. Bulgarian 

Journal of Plant Physiology 28: 66-74. 

Dioniso-Sese ML, Tobita S (2000) Effects of salinity on sodium content and photosynthetic responses of rice seedlings 

differing in salt tolerance. Journal of Plant Physiology 157: 54-58. doi:10.1016/S0176-1617(00)80135-2 

Dodd GL, Donovan LA (1999) Water potential and ionic effects on germination and seedling growth of two cold desert 

shrubs. American Journal of Botany 86: 1146-1153. 

Ellis RA, Roberts EH (1981) The quantification of ageing and survival in orthodox seeds. Seed Science Technology 9: 

373-409. 

Farooq M, Basra SMA, Saleem BA, Nafees M, Chishti SA (2005) Enhancement of tomato seed germination and seedling 

vigour by osmopriming. Pakistan Journal of Agricultural Sciences 42(3-4): 36-41. 

François LE, Bernstein, L (1964) Salt tolerance of safflower. Agronomy Journal 54:38-40. 

Grieve C, Fujiyama MH (1987) The response of two rice cultivars to external Na + /Ca + ratio. Plant Soil 103: 345-250. 

Hopper NW, Overholt JR, Martin JR (1979) Effect of cultivar, temperature and seed size on the germination and 

emergence of soybeans (Glycine max). Annals of Botany 44: 301-308. 

Jumsoon K, Jeuonlai C, Ywonok J (1996) Effect of seed priming on the germinability of tomato (Lycopercicon esculentum 

Mill.) seeds under water and saline stress. Journal of Korean Society of Horticultural Sciences 37: 516-521. 

Kader MA, Jutzi SC (2004) Effects of thermal and salt treatments during imbibition on germination and seedling growth 

of Sorghum at 42/19°C. Journal of Agronomy and Crop Science 190: 35-38. doi: 10.1046/j.0931-2250.2003.00071.x 

Katembe WJ, Ungar IA, Mitchell JP (1998) Effect of salinity on germination and seedling growth of two Atriplex species 

(Chenopodiaceae). Annals of Botany 82: 167-175. 

Kaya MD, Okgu G, Atak GY, Kolsarici O (2006) Seed treatments to overcome salt and drought stress during germination 

in sunflower (Helianthus annuus L.). European Journal of Agronomy 24: 291-295. doi:10.1016/j.eja.2005.08.001 

Khajeh-Hosseini M, Powell AA, Bimgham IJ (2003) The interaction between salinity stress and seed vigor during 

germination of soybean seeds. Seed Science Technology 31: 715-725. 

Maas EV (1986) Salt tolerance of plants. Applied Agriculture Research 1: 12-26. 

Mansour MMF, Salama KHA, Ali FZM, Abou Hadid AF ( 2005) Cell and Plant Repsonses to NaCl in Zea mays L. Cultivars 

Differing in Salt Tolerance. General and Applied Plant Physiology 31(1-2): 29-41. 

82


83 


Murillo-Amador B, Lopez-Aguilar R, Kaya C, Larrinaga-Mayoral J, Flores-Hernandez A (2002) Comparative effects of 

NaCl and polyethylene glycol on germination, emergence and seedling growth of cowpea. Journal of Agronomy 

and Crop Science 188: 235-247. doi:10.1046/j.1439-037X.2002.00563.x 

Nasim M, Qureshi R, Aziz T, Saqib M, Nawaz S, Sahi ST, Pervaiz S (2008) Growth and ionic composition of salt stressed 

Eucalyptus camaldulensis and Eucalyptus teretcornis. Pakistan Journal of Botany 40: 799-805. 

Okcu G, Demir M, Ataka M (2005) Effects of salt and drought stresses on germination and seedlings growth of pea 

(Pisum sativum L.). Turkish Journal of Agriculture 20: 237-242. 

Passam HC, Kakouriotis D (1994) The effects of osmoconditioning on the germination, emergence and early plant 

growth of cucumber under saline conditions. Scientia Horticulturae 57(3): 233-240. doi:10.1016/0304- 

4238(94)90143-0 

Pill WG, Frett JJ, Morneau DC (1991) Germination and seedling emergence of primed tomato and asparagus seeds 

under advers conditions. Horticultural Science 26: 1160-1162. 

Ruan S, Xue Q, Tylkowska K (2002a) Effects of seed priming on germination and health of rice (Oryza sativa L.) seeds. 

Seed Science and Technology 30: 451-458. 

Ruan S, Xue Q, Tylkowska K (2002b) The influence of priming on germination of rice Oryza sativa L. seeds and seedling 

emergence and performance in flooded soil. Seed Science Technology 30: 61-67. 

Singh BG (1995) Effect of hydration-dehydration seed treatments on vigor and yield of sunflower. Indian Journal of 

Plant Physiology 38: 66-68. 

Sivritepe N, Sivritepe HO, Eris A (2003) The effects of NaCl priming on salt tolerance in melon seedlings grown under 

saline conditions. Scientia Horticulturae 97(3-4): 229-237. doi:10.1016/S0304-4238(02)00198-X 

Stofella PJ, Lipucci DP, Pardossi A, Toganoni F (1992) Seedling root morphology and shoot growth after seed priming 

or pre-emergence of bell pepper. Journal of American Society of Horticultural Sciences 27: 214-215. 

Taiz L, Zeiger E (2002) Plant Physiology. 3rd ed, Sinaure Associates, Inc. Publishers, Su and Land, Massachusetts.



Tuz Stresi Altındaki Aspir (Carthamus tinctorius) Bitkisinde Çimlenme ve Fide 

Büyümesinin İyileştirilmesi İçin Tohum Hazırlanması 

Özet 

Giriş: Tuzluluk bazı tahıl bitkisi türlerinde, çimlenmeyi ve fide büyümesini etkilemektedir. Bitkilerin toleransını ve 

büyümelerini iyileştimek için bir çok teknik kullanılmaktadır. Hazırlama, tuzluluk şartları altında bazı ürün bitkilerinin 

çimlenmesini iyileştiren etkili bir tekniktir. Bu yüzden bu deney, beş farklı tuzluluk seviyesine (0, 5, 10, 15 ve 20 g/L) 

maruz bırakılan yalancı safran (Carthamus tinctorius) bitkisinde, 5 g/L NaCl ve KCl ile tohum hazırlamanın çimlenme ve 

fide büyümesi üzerine etkilerini incelemek için gerçekleştirildi. 

Materyal ve Metot: Aspir tohumları, 20°C’de NaCl (5 g/L, 12 s) ve KCl (5 g/L, 24 s) çözeltilerinde ıslatıldı. Islatılmış ve 

ıslatılmamış tohumlar, çimlenmeleri için petri kaplarına kondu ve beş farklı NaCl konsantrasyonu (0, 5, 10, 15 ve 20 g/L) 

içeren tuz çözeltisi ile sulandı. 

Bulgular: NaCl ve KCl ile ıslatma, tuzluluk şartları altındaki yalancı safranda, çimlenme (çimlenme yüzdesi, ortalama 

çimlenme zamanı, çimlenme indeksi ve hız katsayısı) ve büyüme parametrelerini (kökçük ve fide uzunluğu, fide yaş ve 

kuru ağırlıkları ve canlılık indeksi) iyileştirdi. 

Sonuç: Mevcut çalışma, tuz stresi altında, yalancı safran tohum çimlenmesini iyileştirmede NaCl ve KCl ile 

hazırlamanın, bir yöntem olarak kullanılabilceğini ortaya koymuştur. Ancak, NaCl ve KCl ile tohum hazırlamanın, kültür 

ortamında sonraki büyüme ve gelişme üzerindeki etkilerinin gösterilebilmesi için daha fazla çalışmaya ihtiyaç vardır. 

Anahtar Kelimeler: Carthamus tinctorius, çimlenme, fide büyümesi, hazırlama, tuzluluk. 

84

Seed priming to improve germination and seedling growth of ...

Create successful ePaper yourself

Delete template?

Save as template?