International Journal of Farming and Allied Sciences
Available online at www.ijfas.com
©2013 IJFAS Journal-2013-2-S2/1379-1383
ISSN 2322-4134 ©2013 IJFAS
The effects of seed size and salinity on seed
germination characteristic in wheat (var. Chamran)
Seyed Nader Mosavian1* and Morteza Eshraghi-Nejad2
1. Faculty member, Department of Agricultural sciences, payame Noor University, Tehran, Iran
2. Ph.D Student of agronomy, Agriculture and Natural Resiurces of Ramin University, Khozestan, Iran
Corresponding author: Seyed Nader Mosavian
ABSTRACT: Salinity is a determining factor for seed germination. Germination and seedling growth are
the most susceptible stages of plant to salinity stress. In order to the investigation of seed size and
salinity stress on wheat, an experiment was done with three sizes (small, medium and large) of wheat
(var. Chamran) and six level of salinity (0, 25, 50, 75, 100 and 125 mmol NaCl) as a factorial experiment
based on completely randomized design with three replications. The effect of seed size was significant
on RL, SDW and VI2. The effect of seed size was not significant on other traits. Based on LSD test,
small seeds have the GU (46.88 h) and RL (10.79 Cm), but have least SDW (0.01 g) and VI2 (0.89). The
results of ANOVA showed that salinity has the significant effect on Gmax, RL, SL and VI1 (table 1). The
results of regression analysis showed that with increasing salinity levels all of those traits were
decreased linearly (R² varied between 0.6081** to 0.8417**). Therefore using small seeds could help to
use less seed per unite of area. This issue can reduces costs of farmers per unit of area and larger
seeds because of Market-friendly used with factories for oil production and food.
Keywords: germination rate, mean germination time, root length, salinity, seed size, shoot length, Vigor
Index
INTRODUCTION
Salinity is a determining factor for seed germination (Waisel, 1972).Salinity is reported not only to delays, but
also decreases germination of most crops. Lower levels of salinity delay germination, whereas higher levels reduce
the final percentage of seed germination (Ghoulam and Fares, 2001). Salinity due to the toxic effects of salt and
restrict water uptake and root growth, prevent seed emergence (Dellaquila and Spada, 1993). Soltani et al (2002)
showed that salinity affect seedling growth rate, root and shoot length in pea.
Germination and seedling growth are the most susceptible stages of plant to salinity stress. Each plant that
indicate more resistance in these stages, can survive first growth stage successfully (Kent and Lauchil, 1985).
Seed size is an important physical indicator of seed quality that affects vegetative growth and is frequently related
to yield, market grade factors and harvest efficiency (Rukavina et al., 2002). It is affected by variety, environment
and management practices (Robinson, 1978); and so it is commonly variable depending on variation within
population, even in a plant. Opening of all Robinson (1974) found that large seeds produced more vigorous
seedlings compared to small seeds while superiority of crops produced from large seeds was not determined on
seed yield, hectoliter weight and oil percentage. Sung (1992) showed that soybean seed size had a direct effect on
seed germination and vigor. Some researchers showed that large soybean seeds are preferable in stress condition
(Hanley et al, 2007). However, these results varied widely between species. Most investigators have reported a
positive relationship between seedling vigor, improved stand establishment and higher productivity of cereal crops
with plants originating from large seed compared to those grown from smaller seed. With increased seed size
higher germination and emergence were determined in triticale (Kaydan and Yamur, 2008). Effect of seed size on
Intl J Farm & Alli Sci. Vol., 2 (S2): 1379-1383, 2013
germination characteristics of six oat (Avena sativa L.) cultivars under water stress condition were showed that
germination was increased with increasing seed size in oat cultivars (Willenborg et al., 2005). Results of a study
showed that higher vigor that occurred in larger seed is due to the larger food reserves in these seeds (Amico et
al., 1994). Saranga et al. (1998) emphasized that seed vigor was negatively correlated with embryo mass but large
seeds germinated and emerged later than small seeds. Large seed of pearl millet (Pennisetum glaucum L.)
produced higher germination and emergence compared to small seed (Kawade et al., 1987). Similarly, Weimarck
(1975) reported that large seeds germinated better than medium and small seeds, and seedlings from large seeds
had a higher survival rate than smaller seeds under field conditions. Moreover, seed size is positively correlated
with seed vigor, and larger seeds tend to produce more vigorous seedlings (Ries and Everson, 1973). In wheat,
seed size not only influence emergence and establishment but also affected yield components and ultimately grain
yield (Baalbaki, and Copeland, 1997). Other researches demonstrated different results. For instance Rastegar and
aghighi (2011) concluded that Seed size had shown significant effect just on germination uniformity. Peterson et al
(1989) also showed that soybean seed size had not significant effect on rate and the percent of emergence
seedlings.
This research focuses on determining the differences in seed size for germination, seedling growth and seed
vigor. Also, the study aimed to expose the performance of different sized seeds of wheat under saline conditions.
MATERIALS AND METHODS
This study was carried out on wheat seeds (var. Chamran) at the seed laboratory of the Ramin University of
Agriculture and Natural Resources, Iran. This experiment was done with two factors and four replications at
completely randomize design. First factor included of three levels of seed sizes; large seeds (50.60 g), medium
seeds (39.30 g) and small seeds (32.33 gr). Second factor included of seven levels of salinity (0, 25, 50, 75, 100
and 125 mmol nacl). For Standard Germination test, seed samples were sown top paper and kept at a temperature
of 20 °C ± 0.5 in the dark and on the eighth day, normal seedlings were counted and data were expressed as
percentage. For germination rate test, seeds from standard germination test were observed daily and considered
-1
germinated when the radicle was approximately 2 mm long or more. Germination rate (R 50, h ) was then calculated
as (Soltani et al. 2001):
R50 = 1/D50
(1)
Where D50 is the estimation of time taken for cumulative germination to reach 50% of maximum where interpolated
from the germination progress curve versus time.
After 7 days, all germinated seeds were dried at 65ºC in order to dry matter measuring. Maximum of germination
(Gmax), mean germination time (MGT), stem length (SL), root length (RL), seedling dry matter (SEDM) and stem
dry matter (STDM) were measured. Vigour index I and II were calculated as below (Vashisth and Nagarajan,
2010):
VI= Gmax × SL (2)
VI= Gmax × SDM
(3)
Where Gmax, SL and SDM are maximum of germination, seedling length as Cm (stem length+root length) and
seedling dry matter, Respectively.
Mean germination time (MGT) was calculated as equation 4:
MGT= ∑(F.X) ∕ ƩF
(4)
Where F and X were the new germinated seeds at day xi of computation and day’s of computation, respectively
(Matthews & Khajeh-Hosseini, 2007).
All experiments were conducted with the use of a completely randomized design with three replications. The
data were subjected to regression analysis using REG procedures and LSD test was used using GLM procedures
in Statistical Analysis System (SAS) for significantly different at ρ≤0.05 between treatments (SAS Institute 1989).
For salinity treatment that was a quantity factor regression analysis was done.
RESULTS AND DISCUSSION
Seed size. As shown in table 1, the effect of seed size was significant on RL, SDW and VI2. The effect of seed
size was not significant on other traits.
1380
Intl J Farm & Alli Sci. Vol., 2 (S2): 1379-1383, 2013
Table 1. ANOVA analysis of seed size, salinity and their interaction on germination rate to 50% germination (R50), maximum of
germination (Gmax), root length (RL), shoot length (SL), seedling dry weight (SDW), vigor index I (VI1), vigor index II (VI2) and
mean germination time (MGT)
Source
Z
S
S*Z
Error
C.V
DF
2
5
10
36
R50
0.000009 ns
0.000002 ns
0.00004 ns
0.000005
8.58
Gmax
18.074ns
145.541**
24.474 ns
30.222
6.134
RL
21.500**
49.313**
1.885ns
2.980
17.835
Means of Errors
SL
SDW
0.452 ns
0.00001**
**
11.957
0.000001 ns
2.283ns
0.000001 ns
1.824
0.000001
15.891
22.403
VI1
200320.399 ns
1157069.048**
60016.378 ns
75124.363
16.747
VI2
0.807**
0.022 ns
0.064 ns
0.075
24.061
MGT
0.703 ns
2.328 ns
0.799 ns
0.948
9.199
Based on LSD test, small seeds have the higest GU (46.88 h) and RL (10.79 Cm), but have least SDW (0.01
g) and VI2 (0.89) (Fig. 1). Rukavina et al., 2002, reported that in barley, germination was range 97.5% - 98.5% in
four groups of seed sizes and there was no significant difference between them. Also some researchers found
small seeds of sunflower and oat germinated faster compared to large seeds (Kaya and Day, 2008; Saranga et al.,
1998). Rastegar and aghighi (2011) concluded that Seed size had shown significant effect just on germination
uniformity. Peterson et al (1989) also showed that soybean seed size had not significant effect on rate and the
percent of emergence seedlings that conforms this results. The results of Ghorbani et al., (2008) in a research
about the effect of salinity and seed size on response of wheat germination and seedling growth are in line with our
findings. They reported that seed size had significant effect on seedling dry weight. Reported by Al-Karaki (1998)
that lentil seedlings from large seeds had higher root lengths than those from small seeds at intermediate soil water
potential. Therefore, larger seeds had an advantage of seedling establishment in low soil moisture condition due to
larger root system (Leishman and Westoby, 1994). Ghorbani et al., (2008) and Sadeghi et al (2011) reported that
seed size had significant effect on seedling dry weight. Reported by Al-Karaki (1998) that lentil seedlings from large
seeds had higher root lengths than those from small seeds at intermediate soil water potential. Zareian et al. (2013)
showed that seed size had no significant impact on germination percentage
Figure 1. LSD test between seed sizes on germination uniformity (GU), root length (RL), seedling dry weight (SDW) and vigor
index II (VI2)
Salinity effect. The results of ANOVA showed that salinity has the significant effect on Gmax, RL, SL and VI1
(table 1). The results of regression analysis showed that with increasing salinity levels all of those traits were
decreased linearly (fig. 2). Root length was decreased as salinity level was increased (y = -1.0514x + 12.308; R² =
0.7062**). At control level RL equaled to 12.308 and with one unit increasing in salinity, it was decreased -1.0514
units. SL was decreased linearly with increasing in salinity level (y = -0.5516x + 9.8785; R² = 0.8016**). Gmax has
1381
Intl J Farm & Alli Sci. Vol., 2 (S2): 1379-1383, 2013
a negative relation to salinity levels and negatively decreased with increasing in salinity levels (y = -1.6762x +
93.82; R² = 0.6081**). In control level (salinity=0), maximum of germination equaled to 93.82%. With increasing of
salinity, Gmax was declined as negative linearly (-1.6762). The regression equation between VI1 and salinity
showed that there was negative linear relation as (y = -175.83x + 2076.3; R² = 0.8417**), namely with increasing in
salinity level from 0 to 120, vigor index I decreased from 2076.3 with slop of -175.83. Rastegar and aghighi (2011)
reported that Salinity levels hadn’t significant effect of germination percent and uniformity but salinity affects
seedling dry weight. Dodd and Donovan (1999) reported that conditions with higher NaCl contents and water
deficient condition reduces germination due to limited water uptake by the seeds.
Figure 2. Regression analysis of salinity effect on root length, shoot length, maximum of germination (Gmax) and vigor index I
(VI1). Note that this analysis was don only on traits that the salinity effect on it was significant in Anova analysis
The results of this study showed that, seed size has the significant effect on GU, RL, SDW and VI2, but no
significant impact on R50, Gmax, SL, VI1, and MGT. According to this experiment results it is obvious that large
seeds had not special advantages over small ones. Therefore using small seeds could help to use less seed per
unite of area. This issue can reduces costs of farmers per unit of area and larger seeds because of Market-friendly
used with factories for oil production and food.
REFERENCES
Al-Karaki GN, 1998. Seed size and water potential effects on water uptake, germination and growth of lentil. J Agron Crop Sci 181 4: 237-242.
Amico RU, Zizzo GV, Agnello S, Sciortino A, Iapichino G. 1994. Effect of seed storage and seed size on germination, emergence and bulbelt
production of Amaryllis belladonnal L. Acta. Hortic ISHS 362: 281-288.
Baalbaki RZ, Copeland LO. 1997. Seed size, density and protein content effect on field performance of wheat. Seed Sci Technol 25: 511-521.
Dellaquila A, Spada P. 1993. The effect of salinity stress upon protein synthesis of germinating wheat embryos. Annuls of Botany 27:97-101.
Dodd GL, Donovan LA. 1999. Water potential and ionic effects on germination and seedling growth of two cold desert shrubs. Am J Bot 86:
1146-1153.
Ghorbani MH, Soltani A, Amiri S. 2008. The effect of salinity and seed size on response of wheat germination and seedling growth. J Agric Sci
Natur Resour 14(6). 44-52
Ghoulam C, Fares K. 2001. Effect of salinity on seed germination and seedling growth of sugar beet (Beta vulgaris L.). Seed Sci Technol 29:
357-364.
Hanley ME, Cordier PK, May O, Kelly CK. 2007. Seed size and seedling growth: differential response of Australian and British Fabaceae to
nutrient limitation. New Phytologist 174: 381-388.
Kawade RM, Ugale SD, Patil RB. 1987. Effect of seed size on germination, seedling vigor and test weight of pearl millet. Seed Res 15: 210-213.
1382
Intl J Farm & Alli Sci. Vol., 2 (S2): 1379-1383, 2013
Kaya MD, Day S. 2008. Relationship between seed size and NaCl on germination, seed vigor and early seedling growth of sunflower
(Helianthus annuus L.). African Journal of Agricultural Research 3: 787-791.
Kaydan D. Yamur, M. 2008. Germination, seedling growth and relative water content of shoot in different seed sizes of triticale under osmotic
stress of water and NaCl Afri J Biot 7: 2862-2868.
Kent LM, Lauchil A. 1985. Germination and seedling growth of cotton; salinity-calcium interaction. Plant Cell Environ 8:155-159.
Leishman MR, Westoby M. 1994. The role of seed size in seedling establishment in dry soil conditions -experimental evidence from semi-arid
species J Ecol 82(2): 249-258.
Matthews S, Khajeh-Hosseini M. 2007. Length of the lag period of germination and metabolic repair explain vigor differences in seed lots of
maize (Zea mays). Seed Science Technology 35: 200-212.
Peterson CM, Kalepper B, Rickman RW. 1989. Seed reserves and seedling development of wheat. Agronomy Journal 81: 245-251.
Rastegar Z, Aghighi MSK. 2011. The effect of salinity and seed size on seed reserve utilization and seedling growth of soybean (Glycin max).
International journal of Agronomy and Plant Production 2 (1), 1-4.
Ries SK, Everson EH. 1973. Protein content and seed size relationships with seedling vigor of wheat cultivars. Agron J 65: 884886.
Robinson RG. 1974. Sunflower performance relative to size and weight of achenes planted. Crop Sci 14:616-618.
Robinson RG 1978. Production and Culture. In: Sunflower Science and Technology. (Ed. J.F. Carter). Wisconsin, USA pp 89-132.
Rukavina H, Kolak I, Sarcevic H, Satovic Z. 2002. Seed size, yield and harvest characteristics of three Croatain spring malting barleys.
Bodenkultur, 9 53: 1.
Sadeghi H, Khazaei F, Sheidaei S, Yari L. 2011. Effect of seed size on seed germination behavior of safflower (Carthamus Tinctorius L.). ARPN
Journal of Agricultural and Biological Science 6 (4): 5-8,
Saranga Y, Levi A, Horcicka P, Wolf dS. 1998. Large sunflower seeds are characterized by low embryo vigor. Journal of American Society of
Horticultural Science 123: 470-474.
SAS Institute, SASSTAT user's guide, SAS Institute Inc, Cary, 1992.
Soltani A, Zeinali E, Galeshi S, Latifi N. 2001. Genetic variation for and interrelationships among seed vigor traits in wheat from the Caspian Sea
coast of Iran.Seed Science and Technology 29: 653-662.
Soltani A, Galeshi S, Zeinali E, Latifi N. 2002. Germination, seed reserve utilization and seedling growth of chickpea as affected by salinity and
seed size. Seed Sci & Technol 30: 51-60.
Sung FJM. 1992. Field emergence of edible soybean seeds differing in seed size and emergence strength. Seed Science and Technology
20:527-532.
Vashisth A, Nagarajan S. 2010. Effect on germination and early growth characteristics in sunflower (Helianthus annuus) seeds exposed to static
magnetic field. Journal Plant Physiology 167: 149-156.
Waisel Y. 1972. Biology of Halophytes. New York, NY: Academic Press. 396 pp.
Weimarck A. 1975. Kernel size and frequency of euploids in octoploid triticale. Hereditas 80: 69-72.
Willenborg CJ, Wildeman JC, Miller AK, Rossnaged BG, Shirtliffe SJ. 2005. Oat germination characteristics differ among genotypes, seed sizes
and osmotic potentials. Crop Science 45: 2023-2029.
Zareian A, Hamidi A, Sadeghi H, Jazaeri MR. 2013. Effect of Seed Size on Some Germination Characteristics, Seedling Emergence
Percentage and Yield of Three Wheat (Triticum aestivum L.) Cultivars in Laboratory and Field. Middle-East Journal of Scientific
Research 13 (8): 1126-1131
1383