A S Bhoite

M V Gokhale

N S Chavan

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ISSN 2320-5407                             International Journal of Advanced Research (2013), Volume 1, Issue 10, 304-309 
 
304 
 
                                                   Journal homepage: http://www.journalijar.com                 INTERNATIONAL JOURNAL 
                                                                                                                           OF ADVANCED RESEARCH 
                                                                                                                               
RESEARCH ARTICLE 
 
SEED RECALCITRANCE: A MAJOR CONSTRAINT IN THE REGENERATION OF A CRITICALLY 
ENDANGERED MANGROVE SPECIES CYNOMETRA IRIPA KOSTEL 
 
M. V. Gokhale
1
, N.S. Chavan
2
 and A. S. Bhoite
3
 
1 Department of Botany, K.B.P. College, Urun-Islampur, Dist. Sangli - 415 409, (MS-India). 
2. Department of Botany, Shivaji University, Kolhapur 416 004, (MS-India). 
3. Pro. Vice Chancellor, Shivaji University, Kolhapur, 416 004, (MS-India). 
 
Manuscript Info                  Abstract  
 
Manuscript History: 
 
Received: 12 November 2013 
Final Accepted: 18 November 2013 
Published Online: December 2013                                          
 
Key words:  
Mangrove, Cynometra iripa Kostel., 
Seed recalcitrance. 
 
 
Cynometra iripa Kostel is one of the narrowly distributed mangrove species 
in India. It belongs to family Caesalpiniaceae without typical vivipary or 
cryptovivipary. Natural regeneration of the species is very poor. The seeds 
are recalcitrant, lacking seed dormancy. The present paper reports eco-
physiological aspect of seed recalcitrance in the species.   
 
 
 
 
                   Copy Right, IJAR, 2013,. All rights reserved.
 
Introduction   
Seed dormancy is an adaptive trait that improves survival of the next generation by optimizing the distribution of 
germination over time. There are critical checkpoints at the transactions from dormancy to germination and from 
germination to growth. Most of the species exhibit a critical capacity to control the timing of their reproduction and 
the establishment of a new generation of off-springs. For exhibiting the dormancy the seed tissues show outstanding 
feature of desiccation. 
 Non dormant or desiccation intolerant seeds are of two types - viviparous and recalcitrant. Plant species in 
which the embryo grows sufficiently to enlarge visibly from within the seed tissues before dispersal are termed as 
viviparous (Tomlinson, 1986). In another set of species the embryo sustains metabolic activity throughout ontogeny 
but bursts the seed tissues shortly after dispersal. In natural populations, these seeds may germinate readily within 
the fruit or soon after dehiscence, and they do not persist in the soil bank. These type of embryos rapidly loose 
viability if they are dried or chilled; hence they are termed as recalcitrant to storage (Roberts, 1973). The term 
recalcitrant is generally applied to seeds that have been systematically tested to determine their ability to tolerate 
desiccation (Ellis et al., 1985). The inability to store seeds of these species creates challenges for germplasm 
conservationists; foresters concerned with tropical and temperate forest regeneration and restoration ecologists. 
Therefore, in devising seed storage schemes, substantial efforts are essential to systematically diagnosing types and 
causes of recalcitrant behaviors (Pritchard et al., 1996). 
 
Material and Methods  
 The fruits of Cynometra iripa Kostel were collected from the population at Achara estuary (Sindhudurga 
District of State Maharashtra, India). Fruits are non-dehiscent single seeded pods; fruit wall and seed coat are fused. 
Therefore, entire fruit is the propagatory material. Different developmental stages of fruits were identified as follows 
(Figure I).   
Stage Description 
I About a month after fertilization, fruit 0.9 to 1.2 cm in length with greenish, 
photosynthetic fruit wall, embryo axis and cotyledons are clearly visible and 
separable. 
II About three months after fertilization, fruits 1.5 to 2.1 cm in length with brown 
ISSN 2320-5407                             International Journal of Advanced Research (2013), Volume 1, Issue 10, 304-309 
 
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colored tough fruit wall lacking chlorophyll. 
III At the time of fruit shading (about 5.5 to 6 months after fertilization), Fruits mature, 
2.5 to 3.5 cm in length with tough, leathery, thick fruit wall without chlorophyll.    
  
  
Fruits of respective stage were brought to the laboratory, embryo axis and cotyledons were separated and analyzed 
for proline (Sadasivam and Manickam, 1991), proteins (Lowry et al., 1951), free amino acids (Sadasivam and 
Manickam, 1991), carbohydrates (Nelson, 1944), -amylase (Sadasivam and Manickam, 1991), Lipid peroxidation 
(Cacmak and Horst, 1991) and Abscisic acid (ABA) contents (Nayyar and  Walia , 2004; Wang et al, 2002). 
Moisture contents were estimated by oven drying the embryo and cotyledons separately in oven. 
 The mature fruits were kept in the lots of 30 each, in polythene bags under laboratory conditions. Three lots 
differently were analyzed for moisture content and germination percentage immediately and after each week of 
storage. Germination was studied on soil. Root: Shoot ratio was studied at the interval of 5 days. 
 
Results and Discussion 
 Regeneration of mangrove species proceeds along the four different lines viz. vivipary, crypto-vivipary, 
seed germination on soil and vegetative mode of propagation. Physiology and ecology of vivipary and crypto-
vivipary in mangroves is well discussed topic. But regeneration of species in which seeds germinate on soil, is 
crucial. The present paper reports ecophysiology of seed recalcitrance in Cynometra iripa. It is one of the back 
mangal narrowly distributed in India. It is critically endangered at some places (Bhosale, 2002). It requires 
standardization of protocols for large scale regeneration in the estuarine ecosystem.  
 Phenology of C. iripa is discussed by Chavan and Gokhale (2013). At the time of fruit shading, seeds 
exhibit fully mature embryos (Figure II). If the mature fruits kept in moist conditions the seeds germinate and radicle 
emerges out (Figure III). Observations on Root: Shoot ratio in the seedlings, up to 65 days are recorded in Table 1. 
Here root length increases but strikingly shoot length (Plumule) remain constant almost up to a month. Later on it 
starts to increase and grow very slowly. 
              Immediately after fruit fall, the seeds exhibit about 50% moisture content. But the seeds get dry very 
rapidly and after storage of a month the moisture levels decrease up to 21%. As per decrease in the seed moisture 
content, germination percentage also decreases. It is to be noted here that after the period of about 3 weeks (21 days) 
seeds cannot germinate. Therefore 37% seed moisture level is the critical checkpoint in retarding germination in C. 
iripa (Table 2). 
 Stage wise physiological analysis of seeds was carried out separately for embryo axis and cotyledons.  
 Concentration of proline, proteins and free amino acids is depicted in Table 3. Embryo axis is rich in 
proline than cotyledons. Proline accumulation is observed in embryo axis at the time of fruit detachment. In 
cotyledons, proline content decrease from young stage to mature stage of fruit. 
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Figure 3: Growth of radical 
 
 
 
 
Table 1: Observations on Root: Shoot ratio in seedlings up to 65 days of growth. 
 
Days of 
germination 
*Root 
length 
*Shoot 
length 
Root: Shoot 
ratio 
 
1 0.3 0.5 0.6  
 
 
Epicotylar 
dormancy 
period 
5 2.3 0.5 4.6 
10 2.8 0.5 5.6 
15 3.1 0.5 6.2 
20 3.2 0.5 6.4 
25 3.5 0.5 7.0 
30 3.7 0.5 7.4 
35 4.1 0.6 6.8 
   
  Increment in 
shoot height 
40 4.2 0.6 7.0 
45 4.5 0.9 5.0 
50 4.8 1.2 4.0 
55 5.2 1.5 3.4 
60 6.5 1.9 3.4 
65 7.1 2.3 3.0 
*Average of five seedlings 
 
 
 
 
 
 
 
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Table 2: Effect of seed (as a whole, embryo axis + cotyledons) moisture content on germination percentage in 
C. iripa 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Table 3: Concentration of proline, proteins and amino acids in embryo and cotyledons of C. iripa 
 
 
 
 
 
 
 
 
 
 
 
 
 
Table 4: Concentration of soluble sugars, starch and activity of enzyme α- amylase in embryo and cotyledons 
of C. iripa 
 
Table 5: Moisture contents, concentration of Abscissic acid (ABA) and lipid peroxidation in embryo and 
cotyledons of C. iripa 
 
 
 
Water content 
% 
ABA 
ng/1g fresh wt 
Lipid peroxidation 
Μ mole MDA/g fresh wt 
Stage Embryo axis Cotyledons Embryo axis Cotyledons Embryo axis Cotyledons 
I 43 
 
51 61.24 228.02 50 60 
Time period 
in days 
Water content 
% 
Germination 
% 
1 
 
49±3 70 
7 
 
45±5 65 
14 
 
37±2 30 
21 
 
30±5 00 
28 
 
28±2 00 
35 
 
21±3 00 
 Proline 
mg/100 g 
Proteins 
mg/100g 
 
Free amino acids 
mg/100g 
Stage Embryo 
axis 
Cotyledons Embryo 
axis 
Cotyledons Embryo 
axis 
Cotyledons 
I 
 
180 123 2880 2130 790 738 
II 
 
137 67 3539 1893 815 530 
III 
 
360 58 630 970 2300 351 
 Soluble sugars 
mg/100 g 
Starch 
g/100g 
Amylase 
ΔOD/ hr/mg Protein 
Stage Embryo 
axis 
Cotyledons Embryo axis Cotyledons Embryo axis Cotyledons 
I 2193 
 
1321 1.030 3.781 0.21 0.01 
II 2835 
 
2207 0.958 10.938 1.08 0.35 
III 2600 
 
3765 0.840 7.125 0.73 1.70 
ISSN 2320-5407                             International Journal of Advanced Research (2013), Volume 1, Issue 10, 304-309 
 
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II 60 
 
57 76.00 80.30 80 90 
III 47 
 
63 108.20 15.39 190 130 
 
Embryo axis is also rich in proteins and free amino acids than cotyledons. Both, proteins and free amino acids are 
decreasing as per development in cotyledons. 
 Soluble sugars, starch contents and -amylase activity is recorded in Table -4. Highest concentration of 
soluble sugars is recorded in cotyledons at maturity. Cotyledons are rich in starch also. 
 Activity of an enzyme -amylase is increased in cotyledons but in embryo axis primarily it is low, then 
increases and again decreases. 
 Table 5 depicts the moisture content, concentration of ABA and lipid peroxidation. In cotyledons moisture 
content increase as per the development of fruit, but in embryo axis it decreases at maturity. ABA accumulates in 
embryo axis at maturity while it slowly decreases in cotyledons. Lipid peroxidation increases in both as per the 
progress in development. Embryo axis shows maximum lipid peroxidation at maturity. 
 The results suggest that, physiological behavior of embryo axis and cotyledons is different. At maturity, 
cotyledons start starch hydrolysis at very faster rate when due to accumulation of ABA embryo axis becomes 
physiologically inactive. Nutritionally rich cotyledons readily attacked by insects and fungi followed by drying and 
seeds fail to germinate. 
 Root: Shoot ratio in the seedlings and accumulation of ABA in embryo axis provide sufficient ground to 
classify it as physiological epicotylar dormancy. It is prevalent in other species Cynometra cauliflora L. (Jayasuria 
et al., 2012). 
 Effect of seed moisture content on germination percentage suggests the desiccation intolerance of seeds. 
This phenomenon is also observed in Cynometra bauhinifollia Benthan by Nazario et al. (2008). 
 One unique phenomenon was observed in Cynomera iripa during field visits. The seeds in the fruits 
matured during heavy rain, germinate when the fruits are attached to the mother plant similar to crypto-vivipary or 
vivipary. If these fruits are kept in moist conditions remain viable up to 25 to 30 days. During storage, radical grows 
but plumule remains as it is. 
 As a backmangal, C. iripa has narrow ecological amplitude in the costal ecosystems. Moreover, desiccation 
intolerance and epicotylar dormancy may be the prevalent reasons behind rarity of species. Further research is 
needed to break physiological epicotyle dormancy to ensure regeneration of the species. 
 
Acknowledgements  
M. V. Gokhale is thankful to University Grants Commission, New Delhi, for providing generous grant. 
 
References  
Bhosale, L.J., Banik, S., Gokhale M.V. and Jayapp M.A. (2002). Occurrence of Xylocarpus granatum Koen and 
Cynometra iripa Kostel along the coast of Maharashtra. J. Econ. Taxon. Bot. 26, 82-87. 
Chavan, N.S. and Gokhale, M.V. (2013). Phenological events of critically endangered mangrove species along the 
coast of Maharashtra. In : Bhatt J.R., Ramakrishna, Sanjapp M., Remadevi O.K., Nilaratha B.P. and Venkataraman 
K. (eds) Mangroves of India : their biology and uses, Zoological Survey of India, XVI, 640 pp. 
Cakmak, I. and Horst, J.H. (1991). Effect of alluminium or lipid peroxidation, superoxide dismutage, catalase and 
paroxidation activities in root tip of soybean (Glycine max). Physiologia Plantarum, 83 : 463-468. 
Ellis, R.H., Hong T.D. and Roberts E.H. (1985). Handbook of Seed Technology for Genebanks Volume I. Principles 
and Methodology. Rome, Italy. IBPGR. 
Jayasuria Gchan K.M.G., Wijetunga A.S.T.B., Baskin J.M. and Baskin C.C. (2012). Physiological epicotyl 
dormancy and recalcitrant storage behaviour in seeds of two tropical Fabaceae (Subfamily Caesalpinioideae) 
species. AoB PLANTS : Pls 044, doi : 10.1093/aobpla. 
ISSN 2320-5407                             International Journal of Advanced Research (2013), Volume 1, Issue 10, 304-309 
 
309 
 
Lowry, O.H., Rosenbrough, N.T., Farr, A.I. and Randall, R.J. (1951). Protein Measurement with Folin Phenol 
Reagent. J. Biol. Chem. 1993 : 262-275. 
Nayyar, H. and B.P. Walia (2004). Genotypic variation in wheat in response  to water stress and abscisic acid 
induced accumulation of osmolytes in developing grains. Agronomy Crop Science. (190) : 39 to 45. 
Nazario, P., Ferreira A.D.N., Reboucas, E.R. (2008). Germination of Cynometra bauhiniifolia Benthan (Jutairana) 
seeds in terms of desiccation and maintenance under humid conditions. Acta Amazonica Vol. 38 (3) 439-444. 
Nelson, N. (1944). A Photometric adaptation of the Somogy method for the determination of glucose. J. Biol. 
Chem., 153 : 375-380. 
Pritchard, H.W., Tompse H.P.B. and Manger K.R. (1996). Development of a thermal time model for the 
quantification of dormancy loss. Seed Science Research. 6 : 127-135. 
Roberts, E. H. (1973). Predicting the storage life of seeds. Seed Sci. Technol.  
1 : 499-514. 
Sadasivam, S. and Manickam, A. (1991). Biochemical Methods for agricultural Sciences, Willey Eastern Limited. 
Tomlinson, P.B. (1986). The Botany of Mangroves Cambridge University Press, 419 pp. 
Wang, Z. S., Mambelli and E.L. Setter (2002). Abscisic acid metabolism in maize kernels in respect to water 
deficient at early endosperm development. Ann. Botany. 19 : 623-630. 
 


SEED RECALCITRANCE: A MAJOR CONSTRAINT IN THE REGENERATION OF A CRITICALLY ENDANGERED MANGROVE SPECIES CYNOMETRA IRIPA KOSTEL

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SEED RECALCITRANCE: A MAJOR CONSTRAINT IN THE REGENERATION OF A CRITICALLY ENDANGERED MANGROVE SPECIES CYNOMETRA IRIPA KOSTEL

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