全 文 ：Study on Characters of Hard Seeds of
Amphicarpaea edgeworthii Benth. (Leguminosae)
and Methods for Breaking Dormancy
Lifeng ZHANG, Xingwen WU, Yuehui SHE*
College of Agronomy, Sichuan Agricultural University, Chengdu 611130, China
Supported by the Twelfth Five-Year Key Project for Crop Breeding of Sichuan
Province (YZGG 4-6); the Special Support Program for the Scientific Research
Personnel of Sichuan Agricultural University.
*Corresponding author. E-mail: syuehui@sina.com
Received: May 28, 2012 Accepted: August 10, 2012A
Agricultural Science & Technology, 2012, 13(9): 1885-1890
Copyright訫 2012, Information Institute of HAAS. All rights reserved Agronomy and Horticultrue
Abstract [Objective] This study aimed to understand the characters of hard seeds of
Amphicarpaea edgeworthii Benth. (Leguminosae) and explore the methods for break-
ing dormancy. [Method] For both aerial and subterranean seeds of A. edgeworthii,
the morphological characteristics were observed and the appropriate temperature for
germination was explored. For aerial seeds of A. edgeworthii, the characters of hard
seeds were studied, and concentrated sulfuric acid treatment, hot water soak treat-
ment and mechanical damage treatment were compared to explore the methods for
breaking seed dormancy. [Result] The aerial seeds were oblate and averaged 3.38
mm in length, 3.02 mm in width, 1.88 mm in thickness, 15.32 g in thousand grain
weight, with a hard seed rate after of up to 98% natural maturation. The subter-
ranean seeds were approximately oblate with a maximum diameter of 15 mm and a
hundred grain weight of (50.08 -58.26 g); among all the treatments for breaking
hardseededness, cutting seed coat treatment and concentrated sulfuric acid treatment
for 20 minutes were the most effective methods, whereas hot water soak treatment
was the least effective method; constant temperature between 20 and 30 ℃ was op-
timum for the germination of aerial seeds, and alternative temperature of 30/20 ℃
was most appropriate for the germination of subterranean seeds. [Conclusion] Cutting
seed coat treatment and concentrated sulfuric acid treatment for 20 minutes were
the most effective methods to break the hardseededness of A. edgeworthii.
Key words Amphicarpaea edgeworthii Benth. (Leguminosae); Breaking dormancy;
Germination; Hardseededness; Seeds
A mphicarpaea edgeworthii Be-nth., also called Sanziliang-xingdou, Yinyangdou, Shan-
badou, belongs to Amphicarpaea in
Faboideae of the Leguminosae family,
which is an annual twining herb[1]. It is
widely spread across the country, of-
ten distributed along hillside with an
altitude of 300-1 800 m and roadside,
in open field and grassland with strong
shade tolerance. According to records
in Compendium of Chinese Medicinal
Material Resources and Medicinal
Flora of Jiangxi, the seeds can be
used as medicine for curing gynaeco-
logic diseases. Both aerial and Sub-
terranean parts of A. edgeworthii can
seed. The seeds containing isoflav-
ones have anti-inflammatory, antioxi-
dant, antineoplastic and antibacterial
functions[2]. Hardseededness, a com-
mon phenomenon in Plantae, is a form
of seed dormancy, which is a charac-
ter beneficial for the continuation and
transmission of plant species. To date,
reports on hardseededness of A. edg-
eworthii has not been seen yet. This
study explored the physical properties,
the methods for breaking hardseeded-
ness, and germination temperature of
A. edgeworthii seeds, with the goal to
provide theoretical references for the
exploitation and utilization of A. edge-
worthii resource, as well as the do-
mestication and cultivation of this
species.
Materials and Methods
Experimental materials
Aerial seeds of A. edgeworthii
were collected from the shady slope of
Laoban Mountain in Ya’an City of
Sichuan Province. After air drying at
room temperature in the laboratory,
the seeds were placed in a storage
box for later use at 5℃.
Measurement items and methods
Measurement of morphological ch-
aracteristics, thousand grain wei-
ght and hard seed rate ① Morpho-
logical characteristics measurement.
The color and shape of seeds were
observed visually; the size of 50 seeds
selected randomly was measured by a
vernier caliper, and then the average
was calculated. ② 1 000-grain weight
measurement. A hundred seeds were
selected randomly, and weighed. The
average of five repetitions was calcu-
lated. ③ Hard seed rate. A hundred
seeds selected randomly were placed
in a small beaker and immersed in
distilled water for 24 h. Subsequently,
the non-imbibed seeds were counted
for calculating the hard seed rate.
The average of three repetitions was
calculated.
Measurement of water absorption
rate After weighed, two hundred
seeds without any treatment and the
same number of seeds with a small
part of seed coat cut for each were
placed in a small beaker with 20 ml of
warm water at 45 ℃ , and stirred until
cooling, respectively. Then the beak-
ers were transferred into an incubator
for soaking seeds at 25℃. After 6, 12,
24, 36, 48, and 72 h, the seeds were
taken out of the beaker. After absorb-
ing the floating water on the surface by
a filter, the seeds were weighed and
DOI:10.16175/j.cnki.1009-4229.2012.09.029
Agricultural Science & Technology
Agricultural Science & Technology Vol.13, No.9, 2012
2012
the data was recorded. Each treat-
ment was replicated three times, and
the average was calculated. Water ab-
sorption rate was determined by the
following formula:
Water absorption rate(%)= ［(Seed
weigh after water absorption - Seed
weigh before soaking) / Seed weigh
before soaking］×100%
Treatments for breaking hardseed-
edness ① Concentrated sulfuric
acid treatment.Aerial seeds of A. edg-
eworthii were soaked in 98% concen-
trated sulfuric acid for different time (5,
10, 15, 20, 25 and 30 min) with con-
stant stir. After that, the seeds were
immediately washed under tap water,
followed by immersion in tap water for
30 minutes. Subsequently, the seeds
were sowed in moist sterilized sands
to conduct a germination test in an illu-
minating incubator at 25℃ under con-
dition of 12 light hours per day(S). The
germination potentials and germina-
tion rates were investigated and cal-
culated. Each treatment with 50 seeds
was replicated three times.② Hot wa-
ter soak treatment. Aerial seeds of A.
edgeworthii were soaked in hot water
with constant temperature of 90, 80,
70 and 60 ℃ for 30 min. After soak,
the seeds were sowed in moist steril-
ized sands to conduct a germination
test in an illuminating incubator at 25
℃ under condition of 12 light hours per
day (S). The germination potentials
and germination rates were investigat-
ed and calculated. Each treatment with
50 seeds was replicated three times.
③ Grind with sands treatment: Aerial
seeds of A. edgeworthii and coarse
sands were mixed together at a ratio of
2:1 by volume, and grinded in a mortar
until the seed surface was tarnished.
Then, the seeds were immediately
washed under tap water, followed by
immersion in tap water for 30 minutes.
Subsequently, the seeds were sowed
in moist sterilized sands to conduct a
germination test in an illuminating in-
cubator at 25 ℃ under condition of 12
light hours per day (S). The germina-
tion potentials and germination rates
were investigated and calculated.
Each treatment with 50 seeds was
replicated three times. ④ Seed coat
cut treatment. A small proportion of the
seed coat was cut at the back of the
hilum. Then, the seeds were im-
mersed in tap water for 30 min. Subse-
quently, the seeds were sowed in
moist sterilized sands to conduct a
germination test in an illuminating in-
cubator at 25 ℃ under condition of 12
light hours per day (S). The germina-
tion potentials and germination rates
were investigated and calculated.
Each treatment with 50 seeds was
replicated three times. ⑤ Control
treatment. Aerial seeds of A. edge-
worthii were immersed in distilled wa-
ter for 30 min, and sowed in moist
sterilized sands to conduct a germina-
tion test in an illuminating incubator at
25 ℃ under condition of 12 light hours
per day (S). The germination poten-
tials and germination rates were in-
vestigated and calculated. Each treat-
ment with 50 seeds was replicated
three times.
Determination of optimum tempera-
ture for the germination of A.
edgeworthii seeds ① Aerial seeds.
According to the optimal result of dif-
ferent treatments for breaking hard-
seededness, the seeds were first im-
mersed in 98% concentrated sulfuric
acid, and then sowed in moist steril-
ized sands to conduct the germination
test in an illuminating incubator. The
germination test were conducted un-
der constant temperatures(10, 15, 20,
25, 30 ℃ ) and alternative tempera-
tures(20/10℃, 25/15℃), respectively.
The germination potentials and germi-
nation rates were investigated and
calculated. Each treatment with 50
seeds was replicated three times. ②
Subterranean seeds. Subterranean
seeds of A. edgeworthii were sowed in
moist sterilized sands to conduct the
germination test in an illuminating in-
cubator. The germination test were
conducted under alternative tempera-
tures(20/10 ℃, 25/15 ℃ and 30/20 ℃)
with light hours of 12 h per day (S).
The germination potentials and germi-
nation rates were investigated and
calculated. Each treatment with 50
seeds was replicated four times.
Data processing
Germination potential and germi-
nation rate of seeds were determined
by the following formulas:
Germination potential of seeds
(%)= The number of normally germi-
nated seeds in the first 7 days / The
number of experimental seeds ×100%
Germination rate of seeds (%)=
The total number of normally germi-
nated seeds in 15 days / The number
of experimental seeds ×100%
The EXCEL 2003 software was
adopted to process and analyse the
data, testing for significant difference
was accomplished by one-way ANO-
VA and SSR methods.
Results and Analysis
Morphological characteristics of
A. edgeworthii seeds
External characteristics of aerial
seeds The aerial seeds were oblate
and dark brown with black and brown
spots. The hilums were white and
cotyledons were light yellow. The seed
coats were leathery with waxiness,
smooth, lustrous and hard(Fig.1). The
seeds averaged 3.38 mm in length,
3.02 mm in width, 1.88 mm in thick-
ness, 15.32 g in thousand grain weight.
Naturally, the hard seed rate reached
up to 98% after maturation.
External characteristics of subter-
ranean seeds The subterranean
seed was wrapped by a thick sepia-
colored pericarp which was densely
covered with brown tomentum. After
the removal of pericarp, it was the
seed coat with purple spots of different
size, which contains one, sometimes
two seeds inside, with light yellow
cotyledons and radicle (Fig.2). The
embryo had two hypertrophic cotyle-
dons. After dried, the pericarp shrunk
and separated from the seed coat
without dehiscence. The subterranean
seeds were approximately oblate in
shape, different in size and ranged
from 50.08 to 58.26 g in hundred grain
weight, with maximum diameter of up
to 15 mm and minimum diameter of 4-
5 mm.
Water absorption law of A. edge-
worthii aerial seeds Water absorp-
tion rate of aerial seeds without any
treatment rose slowly with the increase
of time, and reached only 5.99% within
6 -72 h. While the seeds after seed
coat cut treatment showed a linearly
increasing trend within 6 h, and then
flattened afterwards. The seeds after
seed coat cut treatment absorbed a lot
more water than those without any
treatment. After 72 h, water absorption
rate of the seeds after seed coat cut
treatment reached up to 109.2%, 18.2
1886
Agricultural Science & Technology
Vol.13, No.9, 2012 Agricultural Science & Technology
2012
Table 1 Germination capacity of the aerial seeds of A. edgeworthii after concentrated
sulfuric acid treatment
Time∥min Germination potential∥% Germination rate∥% Germination index
0 7.3 eF 7.3 gF 4.93 eE
5 50.0 dE 54.7 fE 42.99 dD
10 76.0 bcBC 88.0 cC 77.12 abAB
15 81.3 abBA 94.7 bB 77.17 abAB
20 85.3 aA 99.3 aA 86.18 aA
25 68.7 cCD 82.0 dC 69.82 bBC
30 58.7 dDE 72.0 eD 59.17 cC
Different lowercase letters represent significant differences at 0.05 level; different capital
letters represent significant differences at 0.01 level, according to SSR test.
Table 2 Germination capacity of the aerial seeds of A. edgeworthii after hot water soak
treatment
Temperature∥℃ Germination rate∥% Germination potential∥% Germination index
CK 8.7 b 8.0 a 6.87 a
60 9.3 ab 8.0 a 8.10 a
70 11.3 ab 8.7 a 9.95 a
80 12.0 a 7.3 a 7.12 a
90 11.3 ab 10.0 a 8.89 a
Different lowercase letters represent significant differences at 0.05 level, according to SSR
test.
Fig.3 Water absorption curve of A. edge-
worthii aerial seeds
times as high as that of seeds without
any treatment (Fig.3), indicating that
seed coat was the major barrier a-
gainst imbibition of A. edgeworthii
aerial seeds.
Effect of different treatments on the
germination of A. edgeworthii aerial
seeds
Effect of concentrated sulfuric acid
treatment on the germination of
aerial seeds The germination ca-
pacity of aerial seeds revealed a signif-
icant improvement after concentrated
sulfuric acid treatment compared with
the control (Table 1). The germination
potentials of treated seeds were sig-
nificantly higher than the control (P<
0.05), with increase of 42.7%, 68.7%,
74.0% , 78.0% , 61.4% , 51.4% after
treatment for 5,10, 15, 20, 25 and 30
min, respectively, showing significantly
differences (P<0.01). The germination
rates of seeds after concentrated sul-
furic acid treatment were extremely
significantly higher than the control (P<
0.01). The smallest and the largest in-
creases of germination rate were
47.4% and 92%, respectively, in the 5
and 20 min treatments. In treatments
for 10, 15, 25, and 30 min, the germi-
nation rates of treated seeds were
80.7%, 87.4%, 74.7% and 64.7% high-
er than the control, respectively. After
treated with concentrated sulfuric acid,
the germination indexes of aerial
seeds were significantly higher than
the control (P<0.05). In treatments for
5, 10, 15, 20, 25 and 30 min, the in-
crease were 38.06%, 72.19%, 72.24%,
81.25% , and 64.89% , respectively,
showing extremely differences with the
control (P<0.01). Among them, germi-
nation index of 20 min treatment was
highest, showing extremely significant
differences with 5, 25 and 30 min
treatments and no significant differ-
ences with 10 and 15 min treatments
(P >0.05). In addition, there were no
significant differences among 15, 10
and 25 min treatments (P>0.05). The
germination index of 5 min treatment
was extremely significantly higher than
the control, while extremely significant-
ly lower than the other treatments. The
germination potential, germination rate
and germination index all revealed ris-
ing trend with the increase of time
within 5-10 min, and reached the peak
in 20 min treatment, followed by a de-
clining trend afterwards. Therefore, it
can be concluded that concentrated
sulfuric acid treatment of aerial seeds
was able to improve the water perme-
ability of seed coat and promote seed
germination effectively.
Effect of hot water soak treatment
on the germination of aerial seeds
After hot water soak treatment of A.
edgeworthii aerial seeds for 30 min
under different temperatures, there
were no significant differences of ger-
mination rates, germination potentials
and germination indexes either be-
tween two treatments or between a
treatment and the control, except in
the treatment at 80 ℃ which showed a
significant difference with the control
(P<0.05). The germination capacity of
each treatment was low, with a highest
germination rate of 12% (Table 2).
Therefore, in terms of A. edgeworthii
aerial seeds, hot water soak treatment
was not the most effective method for
breaking seed dormancy caused by
hardseededness.
Effect of mechanical damage treat-
ment on the germination of aerial
seeds Mechanical damage treat-
ment was able to break seed dorman-
cy caused by hardseededness effec-
tively, and improved the germination
A, seed coat; B, hilum.
Fig.1 Morphological characteristics of A.
edgeworthii aerial seeds
A, subterranean pod; B, morphological
characteristics of subterranean seed C,
radicle; D, cotyledon.
Fig.2 Morphological characteristics of A.
edgeworthii aerial seeds
1887
Agricultural Science & Technology
Agricultural Science & Technology Vol.13, No.9, 2012
2012
Table 3 Germination capacity of the aerial seeds of A. edgeworthii after mechanical
damage treatment
Treatment Germinationrate∥%
Germination
potential∥% Germination index
Control 7.3 cC 7.3 cC 4.93 cC
Grind with sands treatment 81.3 bB 62.0 bB 49.19 bB
Seed coat cut treatment 99.3 aA 88.7 aA 63.92 aA
Different lowercase letters represent significant differences at 0.05 level; different capital
letters represent significant differences at 0.01 level, according to SSR test.
Table 4 Germination capacity of aerial seeds under different germination temperatures
Temperature∥℃ Germination rate∥% Germination potential∥% Germination index
15 92.7 abAB 73.3 cC 42.2 cB
20 96.7 aA 96.7 aA 96.6 aA
25 97.3 aA 97.3 aA 116.7 aA
30 87.3 bAB 87.3 bB 112.7 aA
20 ／ 10 68.7 cC 40.0 eD 38.4 cB
25 ／ 15 74.7 cC 60.7 dC 53.8 bB
Different lowercase letters represent significant differences at 0.05 level; different capital
letters represent significant differences at 0.01 level, according to SSR test.
Table 5 Germination capacity of subterranean seeds under alternative temperatures
Temperature∥℃ Germination rate∥% Germination potential∥% Germination index
30 ／ 20 98.33 aA 88.33 aA 21.31 aA
25 ／ 15 71.67 bB 38.33 bB 9.26 bB
20 ／ 10 65.00 bB 15.00 bB 5.31 cC
Different lowercase letters represent significant differences at 0.05 level; different capital
letters represent significant differences at 0.01 level, according to SSR test.
capacity of A. edgeworthii aerial seeds
noticeably (Table 3). Compared with
the control, the germination rates, ger-
mination potentials and germination
indexes of the treatments with the two
mechanical damage methods were
extremely significantly higher than that
of the control (P<0.01). There were al-
so differences of germination rates,
germination potentials and germina-
tion indexes between treatments with
two different mechanical methods.
Germination rate in seed coat cut
treatment was extremely significantly
higher than that in grind with sands
treatment, as well as germination po-
tential and germination index (P<0.01).
It thus proved that the major cause for
the dormancy of A. edgeworthii seeds
was the impermeability of seed coats.
Mechanical treatments can damage
seed coats, improve the permeability,
and thus enabling embryos to imbibe
smoothly, which further promoted
seed germination.
Effect of germination temperature
on the germination capacity of aeri-
al seeds Germination temperature
had significant effect on the germina-
tion capacity of aerial seeds (Table 4).
Under constant temperatures, the ger-
mination rates, germination potentials
and germination indexes rose with the
increase of temperature, and reached
the peak at 25 ℃, followed by a declin-
ing trend. The germination potential
and germination rate of treatment at
25 ℃ were 97.3% and 97.3%, respec-
tively. The former was significantly
higher than that of treatment at 15 and
30 ℃ , but showed no significant dif-
ference with that of treatment at 20 ℃.
The latter was significantly higher than
that of treatment at 30 ℃ (P<0.05), but
showed no significant difference with
that of treatment at 15 and 20 ℃. Un-
der conditions of alternative tempera-
tures, there was no significant differ-
ence between the germination rates of
treatments with two different tempera-
ture combinations. However, under al-
ternative temperature condition of 20
℃ /10 ℃ , seeds germinated obviously
slowly, showing an extremely signifi-
cantly lower germination potential than
that of treatment at 25 ℃ /15 ℃ (P<
0.01). The germination rates and ger-
mination potentials under conditions of
two different combinations were ex-
tremely significantly lower than that of
treatments under constant tempera-
tures (P<0.01). Therefore, it can be in-
ferred that the optimum temperature
for the germination of aerial seeds lay
between 20-25 ℃, and constant tem-
perature was more favorable for the
germination of aerial seeds than alter-
native temperature within the tempera-
ture range designed in our experiment.
Effect of germination temperature
on the germination capacity of sub-
terranean seeds Under alternative
temperature conditions, the germina-
tion rates, germination potentials and
germination indexes of subterranean
seeds were significantly different be-
tween different temperature treat-
ments (Table 5). As can be seen from
Table 5, the germination rates, germi-
nation potentials and germination in-
dexes of subterranean seeds in treat-
ment under 30 ℃/20 ℃ condition were
the highest, extremely significantly
higher than that of treatments at 20
℃ /10 ℃ , 25 ℃ /15 ℃ (P <0.01). The
germination rate, germination potential
and germination index of Subter-
ranean seeds in treatment under 20
℃/10 ℃ were lowest. The germination
rate and germination potential be-
tween treatments under 20 ℃ /10 ℃
and 25 ℃ /15 ℃ were not significant,
but the germination index of treatment
under 20 ℃ /10 ℃ were significantly
lower than that of treatment under 25
℃/15 ℃(P<0.01) .Therefore, it can be
concluded that combination of higher
alternative temperatures is more bene-
ficial for the germination of A. edge-
worthii subterranean seeds.
Conclusion and Discussion
Breaking hardseededness of A. ed-
geworthii aerial seeds to promote
seed germination
Seed dormancy refers to the phe-
nomenon that when a viable seed is
placed under favorable conditions, it
fails to germinate. Seed dormancy
mainly includes embryo dormancy,
seed coat barrier and existing in-
hibitory matter, as well as hardseed-
edness. As a common phenomenon in
legumes, hardseededness is predomi-
nantly caused by the impermeability of
seed coats[3]. Hardseededness is ben-
eficial for the continuation and trans-
1888
Agricultural Science & Technology
Vol.13, No.9, 2012 Agricultural Science & Technology
2012
mission of plant species, however,
which also brings inconvenience to the
utilization and research. There are
many factors causing hardseeded-
ness [4-7]. Uniform germination of hard
seeds can only be guaranteed after
certain treatment. The germination
rate of untreated aerial seeds of A.
edgeworthii is extremely low with a
value of 7.3% ; however, it can be in-
creased to 99.3% after cutting seed
coat, indicating that a primary reason
for seed dormancy of A. edgeworthii
aerial seeds is the impermeability of
seed coats.
Methods for breaking hardseed-
edness mainly include three general
categories: physical, chemical and bi-
ological methods. Among them, con-
centrated sulfuric acid treatment is the
most common chemical method with a
remarkable effect of breaking hard-
seededness, and thus frequently used
to break the hardseededness of
legumes, especially in wild ones [8 ] .
However, time for treating of hard
seeds varies in different legume
species. According to Qiao et al . [9],
concentrated sulfuric acid treatment
for 8-10 min could promote the germi-
nation of Glycine soja Sieb. et Z.
seeds, with germination rate of up to
98% . In another study on Lespedeza
floribunda Bunge, a wild flower plant,
ZHEN et al.[10] discovered that concen-
trated sulfuric acid treatment for 10-30
min could effectively improve the ger-
mination rate, germination potential
and germination index. Xu et al.[11] also
found that concentrated sulfuric acid
treatment for 20 min worked best to
break the hardseededness of Les-
pedeza inschanica (Maxim.) Schindl.
Ma et al. [12] studied the hardseeded-
ness of three wild pasture legumes in
Northwest, and discovered that con-
centrated sulfuric acid treatment for 10
min was enough to break the hard-
seededness of Astragalus fenzelianus
L. effectively, and 30 min was enough
for Astragalus satoi Kitag, while for As-
tragalus floridus Benth, treatment for
40 min was enough to achieve the op-
timal effect of breakdown. In addition,
different strains of the same species
required different time of concentrated
sulfuric acid treatment. For example,
Zhao et al. [13] explored the effect of
concentrated sulfuric acid treatment
on breaking the hardseededness of
Melissitus ruthenica L., and found that
the optimal immersion time for strain
93 -21, strain 90 -36, strain 00 -61,
strain 00-81 was 20, 25, 30 and 40
min, respectively. This may be related
to the different structure and con-
stituents of seed coats in different
plant species or strains. In this study,
taken germination rate, germination
potential and germination index into
consideration, the optimal acid etching
time is 20 min, which is consistent with
the results from Xu and Liu et al[14].
Damaging seeds mechanically is
also one of the effective methods to
break hardseededness. Both the two
methods adopted in our experiment
can improve the germination capacity
of A. edgeworthii aerial seeds with dif-
ference between the results. The ger-
mination capacity of seed coat cut
treatment was significantly higher than
that of grind with sands treatment.
However, the former was time-con-
suming, and thus suitable for treat-
ment of small amounts of seeds. Dur-
ing the grind with sands, the embryos
were damaged or the seed coats were
not damaged effectively for a small
proportion of seeds, due to the uncer-
tain strength and intensity of grind with
sands, which is probably the primary
reason why the germination capacity
of grind with sands treatment was low-
er than that of seed coat cut treatment.
Hot water soak treatment is able
to soften seed coat, remove the waxi-
ness and grease, and thus improving
the permeability and leaching in-
hibitory matter. However, the optimum
temperature varies for different seeds,
and soak time should be determined
based on seed size, seed coat thick-
ness and water temperature[3]. Hot wa-
ter soak treatment of Indigofera am-
blyatha Craib seeds for 25 min at 60℃
worked best [15]. The effect of 30 min
soak treatment of Lespedeza bicolor at
90℃ was better than treatments at the
other temperatures [16]. The effect of
treatment at 80 ℃ was significantly
worse than that of treatments at 90 ℃
and 100 ℃ for Lespedeza formosa
Koehneat seeds [14], and the effect of
treatment at 100 ℃ was the best. For
Kummerowia stipulacea (Maxim.) Ma-
kino seeds, treatment at 80 ℃ had a
bad damage, and insulation treatment
at 50 ℃ for 15 min or at 60 ℃ for 10
min was the optimal method [17]. In our
experiment, the effect of hot water
soak treatment on breaking seed dor-
mancy was not conspicuous. Treat-
ment with boiling water at 100℃ for 30
min has also been tried to break the
hardseededness of aerial seeds, how-
ever, the seeds completely lost the vi-
tality with a germination rate of 0% .
Therefore, hot water soak treatment
was not suitable to break seed dor-
mancy caused by hardseededness.
Optimum temperature for seed ger-
mination
Optimum temperature for seed
germination is directly related to the
choice for sowing period in field.
Seeds with short germination time
germinate early, rapidly and uniformly,
together with high germination rate
and germination index in field, and
thereby it is of great significance to ex-
plore the optimum temperature for
seed germination. Optimum tempera-
ture varies with different plants, both
higher and lower temperatures can re-
duce germination rate, or even induce
seed dormancy. Thermopsis lanceola-
ta seeds germinated best under alter-
native temperature of 23 ℃ /15 ℃ , or
constant temperature of 20℃ or 25℃,
whereas showed a low germination
rate at 15 ℃ or 30 ℃ [18]. Germination
rate of Savia miltiorrhiza seeds re-
vealed a gradually rising trend as tem-
perature increased from 15 to 30 ℃ [19].
Constant temperature of 20 ℃ and al-
ternative temperature of 20 ℃ /30 ℃
could cause Sorbus pohuashanensis
Hedl seeds to produce dormancy,
while lower temperature led to a good
germination effect [20]. The optimal tem-
perature for seed germination of Les-
pedeza floribunda Bunge, a wild flower
plant, was 25 ℃, and germination rate
gradually declined when temperature
exceeded. This study indicated that
constant temperature between 20 ℃
and 30 ℃ was optimum for the germi-
nation of aerial seeds, and alternative
temperature of 30/20 ℃ was most
appropriate for the germination of
subterranean seeds. The reason for
germination temperature difference of
A. edgeworthii seeds requires further
exploration.
1889
Agricultural Science & Technology
Agricultural Science & Technology Vol.13, No.9, 2012
2012
两型豆种子硬实特性及其休眠破除方法
张立峰，吴兴文，佘跃辉 * （四川农业大学农学院，四川成都 611130）
摘 要 [目的] 了解两型豆（Amphicarpaea edgeworthii Benth.）种子硬实特性，探讨破除种子休眠的方法。[方法] 以两型豆种子为材料，观察种子
形态特征，并采用浓硫酸处理、热水烫种、机械损伤等方法处理两型豆地上种子，探讨了两型豆地上种子的硬实特性和破除种子休眠的方法，同时
探讨了两型豆种子萌发的适宜温度。[结果]两型豆地上种子为扁圆形，长 3.38 mm，宽 3.02 mm，厚 1.88 mm，千粒重为 15.32 g，自然成熟后硬实率
高达 98%，地下种子近扁球形，最大直径可达 15 mm，百粒重 50.08～58.26 g；破除硬实方法中，以划破种皮和浓硫酸处理 20 min效果最好，热水
烫种处理效果最差；20 ℃～30 ℃恒温条件下萌发是两型豆地上种子萌发的最适温度，而 30/20 ℃变温为两型豆地下种子萌发的最适温度。[结论]
破除两型豆种子硬实效果最好的方法是划破种皮和浓硫酸处理 20 min。
关键词 两型豆；破除休眠；萌发；硬实；种子
基金项目 四川省“十二五”农作物育种攻关项目（YZGG 4-6），四川农业大学双支计划项目。
作者简介 张立峰（1983-），男，内蒙古赤峰人，硕士研究生，研究方向：作物遗传育种，E-mail: zhlf_1983@163.com。*通讯作者，教授，博士，从事
作物遗传育种方面的研究，E-mail: syuehui@sina.com。
收稿日期 2012-05-28 修回日期 2012-08-10
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Responsible editor: Fujuan QI Responsible proofreader: Xiaoyan WU
References
[1] China Flora Editorial Board(中国植物志
编委会). China flora Vol.41(中国植物志
第 41 卷)[M]. Beijing: Science Press(北
京: 科学出版社), 1995: 257.
[2] HUANG Y(黄芸), QIN MJ(秦民坚 ), YU
GD(余国奠). The distribution of isoflavone
compound in plant and pharmacological
action(异黄酮类化合物在植物界的分布
及药理作用)[J]. Chinese Wild Plant Re-
sources (中国野生植物资源), 2001, 20
(1): 5-7.
[3] YANG QH(杨期和), YIN XJ(尹小娟), YE
WH (叶万辉 ). Dormancy mechanism
and breaking methods for hard seeds
(硬实种子休眠的机制和解除方法 )[J].
Bulletin of Botany (植物学通报), 2006,
23(1): 108-118.
[4] YANG WX(杨文秀), YANG ZR(杨忠仁),
LI HY (李红艳 ), et al. Study on seed
dormary breaking(促进植物种子萌发及
解除休眠方法的研究)[J]. Journal of In-
ner Mongolia Agricultural University (内
蒙古农业大学学报), 2008, 29 (2): 221-
224.
[5] GUO B(郭彪), LEI JZ(雷金芝), MA JL(马
景 林 ). Investigation on soybean hard
seed formation and different varieties
hard seed rate(大豆硬实的形成及不同品
种硬实率的调查)[J]. Modernizing Agri-
culture(现代化农业), 2002(7): 6.
[6] NIU LJ (牛连杰). Causes of seed rigid-
ness and factors related (浅析种子发生
硬实的原因及影响硬实形成的因素)[J].
Seed World(种子世界), 2004(9): 32.
[7] CAO BH (曹帮华), ZHAI MP (翟明普),
GUO JJ(郭俊杰). Study on vigor differ-
ence of seeds with different hard de-
gree in Robinia pseudoacacia(不同硬实
程度的刺槐种子活力差异性研究 ) [J].
Scientia Silvae Sinicae (林 业 科 学 ),
2005, 41(2): 46.
[8] XU BM (徐本美), GU ZH (顾增辉). The
effect of sulphuric acid on hard seed(硫
酸 处 理 硬 实 种 子 的 效 果 ) [J]. Plant
Physiology Communications (植物生理
学通讯), 1985(2): 22-25.
[9] QIAO YK(乔亚科), LI GL(李桂兰), GAO
SG(高书国), et al. Influences of different
methods for treating wild soybean seed
on germination (不同处理方法对野生大
豆种子萌发的影响)[J]. Journal of Hebei
Vocation -Technical Teachers College
(河北职业技术师范学院学报), 2002, 16
(3): 8-9.
[10] ZHENG J(郑健), LI XF(李新凤), GUAN
N(关楠), et al. Germination test of wild
ornamental species Lespedeza flori-
bunda (野生花卉多花胡枝子种子萌发
特性)[J]. Forest Research(林业科学研
究), 2007, 20(6): 879-882.
[11] XU XY (徐兴友 ), LIU YJ (刘永军 ),
MENG XD (孟宪东), et al. A study on
hardseededness and bourgeon char-
acteristic of Lespedeza inschaniea
(Marzm) Schindl(阴山胡枝子种子硬实
与萌发特性研究 ) [J]. Seed (种子 ),
2004, 23(9): 3-5.
[12] MA ZH (马正华), WANG LY (王柳英),
SONG WX (宋维秀). Three wild grass
seed hard characteristics (三种野生豆
科牧草种子硬实特性研究 ) [J]. China
Seed Industry(中国种业), 2009(8): 38-
39.
[13] ZHAO LL(赵丽丽), WANG ZL(王照兰),
DU JC (杜建材 ), et al. The effect of
sulfuric acid treatment on hard seeds
of Melilotoides ruthenica strains (硫酸
处理打破扁蓿豆不同品系种子硬实的
效 果 研 究 ) [J]. Chinese Journal of
Grassland (中国草地学报 ), 2007(3):
73-76.
[14] LIU H(刘红), LIU QH(刘庆华), LIU QC
(刘庆超), et al. Studies on methods of
breaking hard seed of Lespedeza For-
mosa(美丽胡枝子种子硬实破除方法探
讨 ) [J]. Journal of Shandong Forestry
Science and Technology (山东林业科
技), 2006(16): 1-3.
[15] LI CF (李朝凤 ), ZHAO XS 赵小社 ),
WANG YP (王玉萍 ), et al. On hard
seed and germination characteristics
of Indigofera amblyantha (多花木兰种
子硬实与萌发特性研究)[J]. Pruatacul-
ture ＆ Animal Husbandry(草业与畜牧),
2007(12): 8-10.
[16] WUREN QM(乌仁其木). On hard char-
acteristics of Lespedeza bicolor Turcz
hard seed characteristics (二色胡枝子
种子硬实特性的研究 ) [J]. Journal of
Inner Mongolia Institute of Agriculture
and Animal Husbandry (内蒙古农牧学
院学报), 1996, 17(1): 35-40.
[17] SUN Y(孙阳), WANG QL(王全玲), LIU
QH(刘庆华), et al. Studies on the hard
seed explode methods of Kum-
merowia stipulacea(长萼鸡眼草种子硬
实破除方法探讨)[J]. Chinese Agricul-
tural Science Bulletin (中国农学通报),
2008, 24(11): 294-296.
[18] YANG WQ (杨文权), MA JX (马金星),
KOU JC(寇建村), et al. On Salvia mil-
tiorrhiza seed hardness and germina-
tion characteristics(丹参种子硬实与萌
发特性研究)[J]. Seeds(种子), 2009, 28
(4): 88-91.
[19] SUN Q(孙群), LIU WT(刘文婷), LIANG
ZS (梁宗锁), et al. Study on the char-
acter of absorbing water and the ger-
minative condition of Salvia miltiorrhiza
Bunge seeds (丹参种子的吸水特性及
发芽条件研究)[J]. Acta Botanica Bo-
reali-Occidentalia Sinica (西北植物学
报), 2003, 23(9): 1518-1521.
[20] YANG L(杨玲), LIU CP(刘春苹), SHEN
HL (沈海龙). Effects of low tempera-
ture stratification time and germination
temperature on seed germination(低温
层积时间和发芽温度对花揪种子萌发
的影响)[J]. Seeds(种子), 2008, 27(10):
20-25.
[21] DONG SL, ZHANG Y, CHEN NL, et al.
Study on characteristics of seeds dor-
mancy and germination of parasitic
plant Cynomorium songaricum Rupr.
[J]. Medicinal Plant, 2011, 2(1):1-4,12.
1890