Botany
Heteromorphic seed germination and seedling emergence in the legume Teramnus labialis (L.f.) Spreng (Fabacaeae)
Journal: Botany
Manuscript ID cjb-2020-0008.R1
Manuscript Type: Article
Date Submitted by the 17-Feb-2020 Author:
Complete List of Authors: Acosta, Yanier; University of Ciego de Avila Pérez, Lianny; University of Ciego de Avila Escalante, Doris; University of Ciego de Avila Pérez, Aurora; University of Ciego de Avila Martínez-Montero,Draft Marcos; University of Ciego de Avila Fontes, Dayamí; University of Ciego de Avila Ahmed, Lina; INRA Sershen, Sershen; University of KwaZulu-Natal Lorenzo, José; University of Ciego de Avila, Lab for Plant Breeding and Conservation of Genetic Resources
Keyword: animal feed, legumes, seed color, seed dormancy
Is the invited manuscript for consideration in a Special Not applicable (regular submission) Issue? :
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1 Heteromorphic seed germination and seedling emergence in the legume Teramnus
2 labialis (L.f.) Spreng (Fabacaeae)
3 Yanier Acosta1 • Lianny Pérez2 • Doris Escalante2 • Aurora Pérez2 • Marcos Edel
4 Martínez-Montero2 • Dayamí Fontes1 • Lina Qadir Ahmed3,4 • Sershen5 • José Carlos
5 Lorenzo2,*
6 1 Faculty of Agricultural Sciences; 2 Laboratory for Plant Breeding & Conservation of
7 Genetic Resources, Bioplant Center; University of Ciego de Avila, Cuba.
8 3 INRA, UR4 P3F, Unité Pluridisciplinaire Pairies et Plantes Fourragères, Le Chêne -
9 BP 6, F-86600 Lusignan, France
10 4 Department of Field Crops, CollegeDraft of Agriculture, University of Salahaddin, Kirkuk
11 road, 44001 Erbil, Iraq
12 5 Department for Biodiversity and Conservation Biology, University of the Western
13 Cape, Private Bag X17, Bellville, 7535, South Africa
14 * To whom correspondence should be addressed: [email protected]
15
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16 Abstract
17 Seed heteromorphism can influence germination and ultimately seedling establishment,
18 particularly in disturbed habitats. This study compared seed and seedling traits across
19 three distinctly colored seed morphs (viz. light-brown, brown and dark-brown) of the
20 forage legume, Teramnus labialis. Brown seeds were of the best quality (i.e. un-
21 parasitized, filled and un-cracked): 389.3 quality seeds per 1000 units compared with
22 <270/1000 units for the other two morphs. Length, width, volume and water content
23 were lowest in light-brown and highest in dark-brown seeds. Seed thickness and mass
24 were lower in light-brown seeds. Dark-brown seeds imbibed fastest from 2 h onwards.
25 Germination was comparable across morphs after 7 d but lowest in light-brown (17% at
26 21 d) and highest in dark-brown (36%Draft at 21 d) seeds at 14 and 21 d. At 7 d, seedling
27 emergence in dark-brown (15.0%) seeds was higher than in the other two morphs (4-
28 6%); this remained so at 14 and 21 d. Seedling growth (number of leaves, stem height
29 and diameter, and root length) was superior in dark-brown seeds. Seed heteromorphism
30 in T. labialis may allow its persistence in disturbed habitats and dark-brown seeds are
31 best suited for seeding in revegetation projects, given their superior germination
32 capacity and seedling vigor.
33 Keywords: animal feed; crops; legumes; nitrogen fixation; seed color; seed dormancy.
34 Introduction
35 Over the last few decades seed heteromorphism, which involves the production of seeds
36 of different morphologies and/or germination behavior on different parts of the same
37 plant, has been reported in an increasing number of species (Imbert 2002; Lu et al.
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38 2010; Gul et al. 2013; Bhatt and Santo 2016; Hughes 2018). The trait appears to be an
39 adaptation to habitat spatio-temporal variability (Venable et al. 1998; Liu et al. 2018;
40 Ma et al. 2018; Nisar et al. 2019). It can be “cryptic”, i.e. where seed types display
41 different ecological behaviors but no obvious morphological differences (Venable 1985)
42 but in many cases heteromorphism includes variation in seed size, which in turn
43 influences the timing and success of germination, and seedling establishment and
44 survival (Simons and Johnston 2006). When seed size variability influences germination
45 and is fixed through adaptation, the strategy can function as ‘bet-hedging’, where the
46 species brings about a reduction in short-term reproductive success in order to ensure
47 long-term risk reduction (Venable 2007; Matsuo et al. 2016); avoids the negative effects
48 of sib competition (Cheplick 1992) or density (Sadeh et al. 2009) or spreads the risk
49 among many offspring phenotypesDraft (Simons 2011). Importantly, seed heteromorphism
50 often allows a species differential germination behavior and ultimately seedling success,
51 particularly in disturbed habitats (Leverett and Jolls 2014).
52 Seed heteromorphism appears to be confined to representatives of a limited
53 number (n=18) of phylogenetically advanced angiosperm families, in particular the
54 Poaceae, Asteraceae, Chenopodiaceae and Brassicaceae (Imbert 2002). Differences
55 among seed morphs are generally based on one or more of the following: color, size,
56 morphology/anatomy, dispersal syndrome, dormancy and germination (Baskin and
57 Baskin 1998; Volis 2016; Dello Jacovo et al. 2019). The trait has also been reported in a
58 few members of the Fabacaeae (e.g. Amphicarpaea bracteata (Trapp 1988)) and most
59 recently Dello Jacovo et al. (2019) showed that the legume Lathyrus linifolius produces
60 heteromorphic seeds that can be distinguished by differences in seed color; however, the
61 two seed morphs displayed the same germination capacity. Characterizing the
62 phenomenon of seed heteromorphism in legumes is particularly important given the
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63 critical role(s) many members of the family play in agriculture, not only as a source of
64 carbohydrates and proteins for animals and humans but also as nitrogen fixers in
65 different ecosystems (Crews et al. 2016). For example, a rich diversity of legumes, e.g.
66 the genera Neonotonia, Teramnus, Stylosanthes, Centrosema and Macroptilium (Díaz et
67 al. 2012), are gaining popularity as a cover crops in diverse agricultural systems
68 (Mazorra-Calero et al. 2016), including fruit orchards (Grusak 2008).
69 Legumes such as Teramnus labialis (Fabaceae (alt. Leguminosae) tribe) have
70 been shown to be useful in mixed-agricultural systems (Borroto et al. 2007) and can be
71 particularly valuable for sustaining agro-ecosystems and restoring habitats by increasing
72 soil fertility and facilitating the establishment of other species (Acharya et al. 2006; 73 Mondoni et al. 2013). Seeds areDraft essential for these activities, particularly for 74 revegetation of degraded habitats or abandoned agricultural land), However, the use of
75 legume seeds can be problematic due to seed coat-imposed dormancy and/or highly
76 variable germination (Barker et al. 1977; Yuan 2017). The use of T. labialis for
77 example, is far from being maximized owing largely to low seed production, small seed
78 size and highly variable and low germination percentages, most likely due to physical
79 dormancy (González and Mendoza 1991; Acosta et al. 2019).
80 Physical dormancy in legumes is based on the presence of one or more water-
81 impermeable palisade cell layers in the seed coat (Baskin and Baskin 1998). Under
82 natural conditions, the seed coat becomes permeable by weathering or sloughing
83 through the action of one or more environmental factors, but this can take several
84 weeks, to months, which delays the germination and establishment of such species
85 (Smýkal et al. 2014). Researchers and farmers have developed a series of techniques to
86 make dormant seeds permeable, including mechanical scarification, and treatments with
87 sulfuric acid, enzymes, organic solvents, high atmospheric pressures, hot water, dry
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88 storage and low temperatures (Baskin and Baskin 1998; Acosta et al. 2019). The
89 success of these dormancy breaking techniques is challenged by the fact that
90 heteromorphic seeds from a single plant may display a combination of different
91 germination strategies (which can be ‘opportunistic’ or ‘cautious’) (Venable 1985). A
92 field study on the dimorphic seeds of Atriplex prostrata and Salicornia europaea for
93 example, showed that germination was > 90% for large seeds of both species but much
94 lower (>50% and >75%, respectively) for small seeds (Carter and Ungar 2003).
95 During our previous study on T. labialis (Acosta et al. 2019), in which we
96 showed how cryostorage enhances subsequent plant productivity in the forage species,
97 we observed that this species exhibits seed color heterogeneity which is a common 98 indicator of seed heteromorphism.Draft Despite its potential as a cover crop in mixed 99 agricultural systems and value as a potential forage/cover crop for revegetating
100 degraded habitats, there are no published reports on seed heteromorphism in the species.
101 This motivated the present study, which aimed to investigate seed heteromorphism in T.
102 labialis via a comparison of three distinctly colored seed morphs (light-brown, brown
103 and dark-brown) that are produced on the same plant in this species. The specific
104 objectives of the study were as follows:
105 To compare the three seed morphs in terms of physical characteristics;
106 To compare the three seed morphs in terms of imbibition rate and
107 germination capacity;
108 To compare seedling emergence and growth across the three seed
109 morphs.
110 Materials and methods
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111 Plant material: In February 2018 seeds were collected from open pods of 50 randomly
112 selected mature plants belonging to one typical population in Ciego de Avila, Cuba
113 (21.99°06’85” N, 78.76°73’00”W, area sampled = 12 m2). The plant characteristics of a
114 typical T. labialis population in this region are as follows: 560 pods / m2; pod length of
115 c. 3.95 cm; c. 7 seeds / pod with a 1000 seed mass of c. 6.7 g. Pods are mature 35 days
116 (d) after being produced (Acosta et al. 2019) and all three seed morphs can be produced
117 in an individual pod, irrespective of its position on the plant. Once collected, the seeds
118 from different plants were mixed and treated based on recommendations made in the
119 Manual for Seed Management in Germplasm Banks (Rao et al. 2007). The seeds
120 exhibited a moisture content of 9.76% (fresh weight) at harvest and were stored in
121 hermetically sealed glass containers for 5 months at 5°C (Baskin and Baskin 1998),
122 until further use. Draft
123 Phenotypes of seeds: 3000 seeds were randomly selected and divided into three batches
124 of 1000 each. For each batch, the number of good quality (healthy) seeds (un-
125 parasitized, filled and un-cracked) was recorded and these were set aside. Healthy seeds
126 were then divided into three seed morph categories based on their color: light-brown,
127 brown and dark-brown (see Supplementary Fig. A and B). Random samples of seeds of
128 each morph (n=100) were then measured for length, width and thickness using a digital
129 caliper (Stainless Hardened, Germany). Seed mass was assessed by weighing three
130 replicates of 1000 seeds each on an analytical balance (SARTORIUS, Germany). This
131 mass was later divided by 1000 to approximate the mass of an individual seed. The
132 moisture content of seeds was determined by the oven-drying method (ISTA 2005).
133 The volume of seeds was determined using the formula suggested for ellipsoids
134 (Romero-Saritama et al. 2016): seed volume = 4/3 x π x (1/2 x length × width ×
135 thickness). 6 https://mc06.manuscriptcentral.com/botany-pubs Page 7 of 28 Botany
136 Seed imbibitional characteristics: The ability of seeds to imbibe water was measured by
137 weighing the seeds before and during imbibition. Three replicates of twenty seeds each,
138 corresponding to each morph, were weighed and placed in a beaker with 50 ml of
139 distilled water. Every 2 hours, for 24 hours, the seeds were removed from the water,
140 dried with absorbent paper, weighed on an analytical balance (SARTORIUS, Germany)
141 and returned to the water container. The following formula was used to calculate the
142 percentage increase in seed mass: seed mass increase (%) = 100 * (mass of imbibed
143 seeds - mass of seeds before imbibition) / mass of seeds before imbibition.
144 Seed germination and seedling emergence characteristics: For each seed morph, four
145 replicates of 25 seeds each were placed on a single sheet of filter paper within 90 mm
146 plastic Petri-dishes (unsealed). The Draftfilter paper was moistened with 5 mL distilled water
147 every 7 d. Seeds were germinated at 30ºC, 80% relative humidity, in darkness for 21 d
148 in a programmable growth chamber (TOP Cloud-agri, RTOP-1000 B/D, China). Daily
149 germination counts, based on the production of a radicle of ≥2 mm (Baskin and Baskin
150 1998), were taken.
151 In a parallel experiment, 150 seeds of each seed morph were placed in pots (7
152 cm × 7 cm × 14 cm (depth); one seed per pot) containing a mixture of ferralytic-red soil
153 and humus (1:1, v:v) and incubated at 30 ± 1°C, 12/12 hour photoperiod (PPFD: 80
154 μmol m−2 s−1). Pots were irrigated with 25 ml water daily. Seedling emergence counts
155 were conducted daily for 21 d. At 21 d, thirty plants produced from each seed morph
156 were assessed for number of leaves, the length and diameter of stems, and the length of
157 the roots with a digital caliper (Stainless Hardened, Germany).
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158 Data analysis: The data were tested for normality (Shapiro Wilk test) before using a
159 one-way Analysis of Variance (ANOVA) to compare means across the three seed
160 morph categories. Means were compared using a Tukey test at the 0.05 level of
161 significance. All statistical analyses were carried out in SPSS (Version 8.0 for
162 Windows, SPSS Inc., New York). The overall coefficients of variation (OCV) were also
163 calculated as follows: (standard deviation/average) * 100. In this formula, the average
164 values of the three seed morphs were compared (light-brown, brown and dark-brown)
165 and the higher the difference among the three seed groups, the higher the OCV
166 (Lorenzo et al. 2015). OCVs were classified as low from 1.4 to 48.4%, medium from
167 48.4 to 95.0%, and high from 95.0 to 141.6%.
168 Results Draft
169 Phenotypes of seeds
170 The three seed morphs differed significantly in terms of the number of quality (i.e. un-
171 parasitized, filled and un-cracked) seeds per 1000 units. Brown seeds were of the best
172 quality based on visual inspection (Fig. 1A). This morph averaged 389.3 quality seeds
173 per 1000 units while the number of quality seeds belonging to the other two groups was
174 lower: 246.7/1000 units for light-brown seeds and 266.6/1000 units for dark-brown
175 seeds. The OCV for this trait was, however, low (25.6%).
176 The three groups of seeds also differed significantly in terms of seed length (Fig.
177 1B), width (Fig. 1C), thickness (Fig. 1D), volume (Fig. 1E), mass (Fig. 1F) and water
178 content (Fig. 1G). Although the respective OCVs were very low (1.8-8.6%) for these
179 traits, some differences are worth noting: 1) length, width, volume and water content
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180 were significantly lowest in the light-brown seeds and highest in the dark-brown seeds,
181 while values for these parameters in brown seeds were intermediate; 2) seed thickness
182 and mass in light-brown seeds were significantly lower than in the other two seed
183 morphs.
184 Seed imbibitional characteristics:
185 The three seed morphs differed significantly in terms of levels of water uptake during
186 imbibition (Fig. 2) with a medium OCV at 2 h (Fig. 2A) and high OCVs from 4 to 48 h
187 (Fig. 2 B-G). Dark-brown seeds imbibed significantly faster, followed by brown and
188 light-brown seeds. For example, at 12 h dark-brown seeds exhibited c. 30% increase in
189 seed mass increase (Fig. 2F), whileDraft seed mass increased by c. 4% in brown seeds and c.
190 1% in light-brown seeds. These differences in % increase in seed mass were even more
191 evident at 48 h.
192 Seed germination and seedling emergence characteristics:
193 In terms of germination capacity, significant differences were not observed at 7 d of
194 incubation (Fig. 3A) but this changed at 14 and 21 d (Fig. 3B, C). At 14 d, even though
195 the OCV was low (23.7%), the light-brown seeds exhibited significantly lower
196 germination than brown and dark-brown seeds (Fig. 3B). At 21 d (Fig. 3C), the OCV
197 for germination was also low (36.1%) but germination capacity differed significantly
198 across the three groups: 17% for light-brown, 26% for brown and 36% for dark-brown
199 seeds.
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200 Seedling emergence (%) at 7 d of cultivation (Fig. 3D) was associated with a
201 medium OCV (83.4%). On this day, seedling emergence for dark-brown seeds was
202 significantly higher (15.0%) than in the other two groups (in which % seedling
203 emergence ranged from 4-6%) (Fig. 3D). At 14 and 21 d (Fig. 3E, F), the difference
204 among groups was smaller but % seedling emergence was nevertheless significantly
205 highest in dark-brown, and lower in brown and light-brown seeds.
206 After 21 d of growth, the number of leaves per plant (Fig. 3G), stem height (Fig.
207 3H), stem diameter (Fig. 3I) and root length (Fig. 3J) were all significantly highest in
208 seedlings derived from dark-brown seeds and significantly lowest in those derived from
209 light-brown seeds. The OCVs for all these parameters were low but these differences
210 were visually apparent as shown in DraftFig. 3K.
211 Discussion
212 The number of species reported to exhibit seed heteromorphism is steadily increasing
213 (Imbert 2002; Lu et al. 2010; Gul et al. 2013; Leverett and Jolls 2014; Bhatt and Santo
214 2016; Hughes 2018; Sethi et al. 2020). Of the studies that have reported heteromorphic
215 germination, very few have gone to the extent of comparing the class, level and type of
216 dormancy across different seed morphs (Carter and Ungar 2003; Wang et al. 2012), or
217 investigated whether this is accompanied by heteromorphic seedling emergence and
218 growth. This is particularly true for legumes that display seed heteromorphism, where
219 structure and color of the testa can be important traits for predicting seed quality and
220 germination potential (Ochuodho and Modi 2013). Given the wide range of benefits that
221 members of the Fabaceae afford within agro-ecosystems, reliable morphological
222 indicators of seed vigor are particularly important when legumes that display seed
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223 heteromorphism are to be used for applications such as revegetation of disturbed or
224 degraded habitats (Acharya et al. 2006; Mondoni et al. 2013).
225 Seed color can be a useful indicator of seed hardness and germinability in
226 some species (Brochmann 1992; Juan et al. 1994). In the present study we showed that
227 the three distinctly colored seed morphs produced by T. labialis, exhibit significant
228 differences in quality (Hampton 2002). Brown seeds were shown to be of the best
229 quality and dark- and light-brown seeds to be of significantly lower quality. Yildiz
230 Tiryaki et al. (2016) found that in Vicia sativa soft seeds had a light-brown color, while
231 the hard seeds were dark-brown. They associated this with some degree of mechanical
232 or chemical difference in the testa. Buyukkartal et al. (2013) reported that differences in 233 the color of seeds are related to theDraft amount and types of pigments in the testa, which 234 include flavonoids and anthocyanins (Dixon and Sumner 2003). Dark testas have a high
235 concentration of anthocyanins and proanthocyanins in relation to light seeds in some
236 bean varieties (Ranilla et al. 2007) and this may be the case in the three differentially
237 colored seeds morphs identified in T. labialis here. The external appearance of the color
238 of the testa is also influenced by environmental stimuli during seed development (Senda
239 et al. 2004). Environmentally-induced changes in testa color, thickness and composition
240 (Lacey et al. 1997) are common in species in which the seeds undergo a long
241 developmental period that is accompanied by different environmental conditions. This
242 may be applicable to T. labialis, since the period from flowering to seed maturation in
243 this species can take up to four months (González and Mendoza 1995; Acosta et al.
244 2019).
245 In T. labialis there were significant differences among the three seed morphs
246 in terms of seed length, thickness, width, volume and water content. The light-brown
247 and brown seeds were smaller than the dark-brown type in terms of length, width and
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248 volume. The coloration of the testa is not only influenced by the chemical composition
249 but also by the physiological maturity of the seed at shedding, which in turn influences
250 seed dormancy and germination (Yildiz Tiryaki et al. 2016). Several studies have shown
251 that testa pigmentation has a significant influence on water intake (Powell et al. 1986),
252 dormancy (Baskin et al. 2000), germination and emergence of seedlings (Mavi 2010). In
253 this regard, germination and seedling emergence rates in T. labialis were significantly
254 higher in light-brown seeds compared with dark-brown seeds (Fig. 3A-C).
255 Heteromorphic germination has been shown in a number of species, including
256 Cichorium intybus (Pimpini et al. 2002) and Trifolium pratense (Atis et al. 2011;
257 Velijević et al. 2017), but reports of this phenomenon in legumes are not common. 258 Water uptake rates have Draft also been closely related to the color of the testa 259 (Zhang et al. 2008) and size of seeds (Khan and Ungar 2001; Matilla et al. 2005) in a
260 number of species. As alluded to above, the dark-brown seeds were the largest (in terms
261 of volume, length and width) and also exhibited the highest levels of imbibition across
262 the three seed morphs. Water removes the inhibition of germination in orthodox seeds
263 and the superior imbibition rates in dark-brown seeds may explain why these seeds
264 exhibited higher germination capacity and seedling emergence rates than the other two
265 seed morphs. In contrast, the smallest seeds in terms of mass (the light-brown morph)
266 exhibited the lowest levels of water uptake, germination capacity and seedling
267 emergence. These results are in agreement with theoretical models which predict that
268 small seeds are more likely to exhibit delayed germination than large seeds (Venable
269 and Brown 1988; Rees 1994). Some authors believe that since large seeds are more
270 likely to be predated post dispersal than small seeds (Blate et al. 1998), large seeds
271 germinate more rapidly to avoid risks of mortality (Cintra 1997). On the other hand,
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272 small seeds often display delayed germination and may be more persistent in the soil
273 seed bank (Venable and Brown 1988; Rees 1994).
274 The growth and biomass accumulation of plants generated from dark-brown
275 seeds were also clearly better than those generated from the other two seed morphs (Fig.
276 3J-K), supporting the growing body of evidence for the relationship between
277 heteromorphic seed germination and seedling vigor (Springfield 1973; Atis et al. 2011;
278 Velijević et al. 2017). In T. labialis, seed heteromorphism could therefore represent an
279 adaptive strategy where seedlings produced from dark-brown seeds grow vigorously to
280 increase the chances of seed dispersal before plants are grazed as reported for other
281 species (El-Keblawy and Bhatt (2015). Heteromorphic seed production is also one of 282 the most effective strategies for adaptingDraft and increasing the reproductive success of 283 plants in unpredictable climatic conditions (Harper 1977) and disturbed habitats
284 (Leverett and Jolls 2014). This may explain why T. labialis has been shown to persist as
285 a cover crop even in agro-ecosytems that have been subject to high levels of disturbance
286 and poor management in Cuba (Borroto et al. 2007).
287 Conclusion
288 This study showed that the seed color heterogeneity reported for T. labialis is associated
289 with differences in seed quality, and heteromorphic germination capacity and seedling
290 emergence. Differences in germination rates across seed morphs appear to be the
291 product of differences in water uptake rates and seed mass. In this regard, dark-brown
292 seeds imbibed the fastest and exhibited the highest germination rate. In line with the
293 well-established relationship between rapid germination and good seedling
294 establishment, seedling emergence and plant growth were also superior in germinants of
295 dark-brown seeds. Teramnus labialis is presently under-utilized as a cover crop despite
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296 its potential use for revegetating or improving the quality of degraded agricultural land
297 based on poor and highly variable germination. The results of this study suggest that the
298 selective use of dark-brown seeds for these applications could ensure good stand
299 establishment based on the superior germination capacity and seedling vigor of this seed
300 morph. Furthermore, the seed heteromorphism displayed by T. labialis is likely to
301 ensure its persistence in habitats open to disturbance, such as mixed crop-livestock
302 systems.
303 Declarations:
304 Ethics approval and consent to participate: Not applicable.
305 Consent for publication: All authorsDraft agreed to publish this paper.
306 Availability of data and material: Not applicable.
307 Competing interests: Not applicable.
308 Funding: Not applicable.
309 Authors' contributions: YA, LP, DE, AP, MEMM, DF, LQA, S and JCL designed the
310 research; YA, LP and DE conducted the experiment; YA, LP, DE, AP, MEMM, DF,
311 LQA, S and JCL analyzed the data and wrote the paper; and JCL had primary
312 responsibility for the final content. All authors have read and approved the final
313 manuscript.
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314 Acknowledgements: This research was supported by the University of Ciego de Avila
315 (Cuba), INRA (France), the University of Salahaddin (Iraq), and the University of the
316 Western Cape (South Africa).
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Draft
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Fig. 1: Physical characteristics of seeds belonging to the three morphs identified.
Results with the same letter are not statistically different (One-Way ANOVA, p>0.05).
OCV were classified as Low from 1.4 to 48.4%, Medium from 48.4 to 95.0%, and High
from 95.0 to 141.6%. Vertical bars represent SE.
Fig. 2: Change in seed mass during imbibition for the three morphs identified. Results
with the same letter are not statistically different (One-Way ANOVA, p>0.05). OCV
were classified as Low from 1.4 to 48.4%, Medium from 48.4 to 95.0%, and High from
95.0 to 141.6%. Vertical bars represent SE.
Fig. 3: Germination capacity, seedling emergence and seedling growth characteristics for the three seed morphs identified.Draft Results with the same letter are not statistically different (One-Way ANOVA, p>0.05). OCV were classified as Low from 1.4 to 48.4%,
Medium from 48.4 to 95.0%, and High from 95.0 to 141.6%. Vertical bars represent SE.
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