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Distribution and diversity of foliar endophytic fungi in the mangroves
of Andaman Islands, India
T. Rajamani
a
,
c
, T.S. Suryanarayanan
a
,
*
, T.S. Murali
b
, N. Thirunavukkarasu
c
a
Vivekananda Institute of Tropical Mycology, Ramakrishna Mission Vidyapith, Chennai, India
b
Department of Biotechnology, School of Life Sciences, Manipal Academy of Higher Education, Manipal, India
c
PG &Research Department of Botany, Ramakrishna Mission Vivekananda College, Chennai, India
article info
Article history:
Received 20 July 2018
Received in revised form
27 September 2018
Accepted 28 September 2018
Corresponding Editor: James White Jr.
Keywords:
Phomopsis
Plant microbiome
Leaf endophyte
Tropical forest
abstract
Fungal endophytes represent a major component of plant microbiomes. Various aspects of these fungi
such as their diversity and technological potential have been studied in detail. However, their distri-
bution and diversity in a mangrove community has not been addressed. In this study, we report the
presence of culturable fungal endophytes from 20 obligate mangrove hosts from south Andaman Islands.
Phomopsis/Diaporthe was isolated from all the mangrove species studied while Xylaria,Colletotrichum and
Phyllosticta were recorded from the majority of the mangroves studied. A phylogenetic analysis of
representative Phomopsis/Diaporthe isolates clearly indicated the broad host range of this genus. Our
study also highlighted the fact that leaf endophytes of mangroves are not unique with reference to their
species diversity and frequency of occurrence when compared to those of terrestrial plants. These ob-
servations suggest that the extraordinary success of some fungal endophytes in colonizing taxonomically
disparate hosts could be due to development of traits specific to their ecosystem.
©2018 Elsevier Ltd and British Mycological Society. All rights reserved.
1. Introduction
Endophytic fungi infect and live within plant tissues without
inducing any disease. They are ubiquitous and constitute an integral
component of the plant microbiome. Endophyte association in-
creases plant host fitness by enhancing its tolerance to abiotic
(Yamaji et al., 2016;Lata et al., 2018) and biotic (Estrada et al., 2015;
Suryanarayanan et al., 2018) stressors; these filamentous fungi
are thus being investigated for their potential to improve crop
fitness (Vega et al., 2008;Raghavendra and Newcombe, 2013).
Furthermore, endophytic fungi represent a source of novel bioac-
tive molecules (Suryanarayanan et al., 2009;Kharwar et al., 2011;
Kusari et al., 2012) and industrially important enzymes
(Thirunavukkarasu et al., 2011,2015;Suryanarayanan et al., 2012;
Sengupta et al., 2017). There are many studies on endophytes
residing in the leaves of individual angiosperm plants and a few of
them address the status of the foliar endophyte of plant commu-
nities (Suryanarayanan et al., 2003,2011;Arnold and Lutzoni, 2007;
Sudhakara Reddy et al., 2016). Here, we report on the distribution
and diversity of culturable foliar endophytes of mangroves of
Andaman Islands, India.
Mangroves are plants of the tidal habitats and survive in the
ecotone between the terrestrial and marine ecosystems. Mangroves
constitute an unique ecosystem which provides crucial ecosystem
services including fisheries, shoreline shield, carbon sequestration
and bioremediation of wastes (Lee et al., 2014). Furthermore,
mangrove forests support a wide biodiversity and constitute the
most carbon rich forests of the tropics (Donato et al., 2011). Current
satellite data confirm that anthropogenic activity is leading to the
loss of mangrove forests globally (Thomas et al., 2017).
While macroscopic basidiomycetes (Gilbert and Sousa, 2002;
Maekawa et al., 2003;Sakayaroj et al., 2012;Nogueira-Melo et al.,
2014) and marine fungi (Sarma and Hyde, 2001) of mangroves
have been studied for their diversity and distribution at the com-
munity level, investigations on endophytes of mangroves pertain
only to a few mangrove species (Suryanarayanan et al., 1998;
Kumaresan and Suryanarayanan, 2001;Costa et al., 2012;de Souza
Sebastianes et al., 2013;Li et al., 2016) or to their ability to produce
novel bioactive metabolites and extracellular enzymes (Maria et al.,
2005;Aly et al., 2010;Debbab et al., 2013). To our knowledge, there
are no studies involving simultaneous sampling of many mangrove
species to address the diversity and distribution of foliar
*Corresponding author. Vivekananda Institute of Tropical Mycology, RKM
Vidyapith, Chennai, India.
E-mail address: t_sury2002@yahoo.com (T.S. Suryanarayanan).
Contents lists available at ScienceDirect
Fungal Ecology
journal homepage: www.elsevier.com/locate/funeco
https://doi.org/10.1016/j.funeco.2018.09.007
1754-5048/©2018 Elsevier Ltd and British Mycological Society. All rights reserved.
Fungal Ecology 36 (2018) 109e116
endophytes in them. Furthermore, according to Niranjan and Sarma
(2018) there are no studies on the endophytes of Andaman and
Nicobar Islands. We chose to investigate this facet of endophytes of
Andaman Islands (in the Bay of Bengal, east of India, 11.7401
N,
92.6586
E) since 13% of the total mangrove cover of India is present
here (Forest Survey of India, 2013), and the mangroves of this re-
gion exhibit the highest density and growth among the mangroves
of the country (Dagar et al., 1991).
2. Materials and methods
2.1. Sample collection
We chose South Andaman for our study as it supports 23 of
the 25 mangrove species and all the 10 mangrove families
distributed in the Andaman and Nicobar Islands (Goutham-
Bharathi et al., 2014). Mature and healthy leaves of 20 obligate
mangrove species (Goutham-Bharathi et al., 2014) belonging to
10 families were collected from the following seven different
locations in South Andaman Island (Fig. 1,Table 1) and sampled
for their endophyte presence - Burmanallah, Chidiyatapu, Cor-
byn's Cove, Manjeri, Shippighat, Shoal Bay and Wright Myo. The
leaves were transported to the laboratory in sterile bags and
screened for endophyte presence within 48 h of collection, by
surface sterilizing and plating them on nutrient agar medium.
The study involved a one time sampling between May 2016 and
February 2017.
2.2. Surface sterilization
For each mangrove species, a total of 40 leaves were collected
from 4 individual plants (10 leaves/individual). From these, 120
tissue segments (0.5 cm
2
each) were cut from the midrib region
(including the lamina portion) -one each from the apical, middle
and the basal region of the leaf. Of these, 100 leaf segments were
surface sterilized and screened. These leaf segments were surface
sterilized by immersing them in 70% ethanol for 5 s, followed by
treatment with sodium hypochlorite (4% available chlorine) for 90 s
and rinsing in sterile distilled water for 10 s (Suryanarayanan et al.,
1998). The tissue segments were then plated in Petri dishes (9 cm
dia.) containing antibiotic-amended (Chloramphenicol, 150 mg/l)
Potato Dextrose Agar (PDA) medium (20 ml). We had previously
used this sampling design for studying leaf endophytes of trees of
different forest types occurring in the Western Ghats
(Suryanarayanan et al., 2002,2011;Govinda rajulu et al., 2013;
Sudhakara Reddy et al., 2016).
2.3. Incubation procedure and isolation of endophytes
The efficacy of the sterilization protocol in removing the surface
microbes was confirmed (Schulz et al., 1998) and each Petri dish
with ten leaf segments was incubated in a light chamber (12 h light:
12 h dark cycle, 2200 lux of light) at 26
C for 4 weeks
(Suryanarayanan, 1992). The endophytes which grew out of the
tissue segments were isolated, cultured on PDA slants and identi-
fied using standard manuals (Barnett and Hunter, 1998;Ellis, 1971,
1976 ;Ellis and Ellis, 1988;Sutton, 1980;Onions et al., 1981). Isolates
which failed to sporulate were given codes based on culture char-
acteristics such as growth rate, colony surface texture and hyphal
pigmentation (Suryanarayanan et al., 1998) and were assumed to be
different taxonomic species (Bills and Polishook, 1994). Since the
identification was done primarily based on spore morphology, the
anamorph (asexual state) and teleomorph (sexual state) were
enumerated separately.
2.4. Genomic DNA extraction
The genomic DNA was extracted from fresh mycelia collected
from 7 d old cultures growing in PDA medium. For this, the phenol-
chloroform method was used (Sudhakara Reddy et al., 2016). The
extracted DNA was resuspended in 50
m
l of sterile distilled water
and stored at 80
C for further studies. For PCR amplification, the
samples were thawed, concentration of the genomic DNA was
checked in a 1% agarose gel and then used.
2.5. PCR amplification and sequencing of ITS region
A polymerase chain reaction was performed to amplify the ITS
region and its flanking sequences. Fungal specific primers ITS4 and
ITS5 were used for the reaction (White et al., 1990). The PCR reac-
tion mix consisted of PCR buffer, forward and reverse primers,
dNTPs, Taq Polymerase, DMSO, MgCl
2
and fungal DNA and was
Fig. 1. Map of Anda man Islands showing the places of sample collection.
T. Rajamani et al. / Fungal Ecology 36 (2018) 109e116110
carried out in a 25
m
l reaction volume. The reaction conditions
were: 94
C for 3 min; 34 cycles consisting of 94
C for 30 s, 54
C for
30 s and 72
C for 60 s; followed by 72
C for 10 min. The PCR
amplicons were run in agarose gel and gel eluted for purification.
The sequencing reaction was carried out using one of the primers
and sequenced in ABI 3130 Genetic Analyzer. After manual editing,
an initial search was carried out using BLAST to identify the closest
matches. The sequences obtained in the current study were then
aligned with sequences of type materials and sequences showing
higher similarity in Blast search using ClustalW. The aligned se-
quences were then manually realigned again and the phylogenetic
tree was constructed using MEGA6 (Tamura et al., 2013). A
maximum likelihood analysis was performed to understand the
phylogenetic relationship between the isolates. A bootstrap anal-
ysis with 1000 replicates was performed and the consensus tree
was constructed using MEGA6. The sequences were submitted to
GenBank and accession numbers were obtained (MH371241-
MH371256).
2.6. Statistical analysis
The colonization frequency (CF%) of each endophyte was
calculated by the method of Hata and Futai (1995).
CF% ¼Number of segments colonized by each endophyte
Total number of segments observed
100
Fisher's
a
was used to estimate the species diversity of endo-
phytes. The formula for estimating this value is S ¼a*ln (1 þn/a),
where S is the number of taxa, n is the number of individuals, ln is
the natural logarithm and a is the Fisher's alpha. This index was
preferred as it has been shown to be less affected by the abundance
of common species (Magurran, 2004). Statistical programmes Pro
version 2 (The National History Museum and The Scottish Associ-
ation for Marine Science) and EstimateS software version 9.1.0
(Robert K. Colwell, University of Connecticut) [http://viceroy.eeb.
uconn.edu/estimates] were used for calculating the ecological pa-
rameters. To avoid the influence of sample sequence on the prog-
ress of species accumulation, unique species and singleton curves,
the data were randomized 100 times before analysing and plotting
the curves (Suryanarayanan et al., 2011).
3. Results
The number of endophyte isolates that were recovered varied
from 39 in Avicennia marina to 236 in Excoecaria agallocha; the
number of endophyte species isolated ranged from 8 in Bruguiera
parviflora to 23 in Rhizophora apiculata (Supplementary Table 1).
The species diversity of the endophytes was lowest for B. parviflora
(2.1) and highest for R. apiculata (11.4) (Supplementary Table 1).
Phomopsis was the most common endophyte genus recorded and
was isolated from all the 20 mangrove species screened; it
accounted for 377 isolates of the total 2180 isolates obtained from
all the mangroves and hence isolates belonging to this genus were
selected for further molecular characterisation (Fig. 2,Table 2).
Species of Xylaria and Colletotrichum were present in the leaves of
19 mangroves. Phyllosticta capitalensis was the densest endophyte
as 545 isolates of it were isolated from 18 mangrove species. Col-
letotrichum gloeosporioides, Phyllosticta capitalensis, Phomopsis spp.
(along with the teleomorph Diaporthe spp.), or Xylaria spp. (along
with the anamorph Nodulisporium spp.) dominated or occurred as
co-dominant species in the endophyte assemblage of different
mangrove species studied (Table 3). C. gloeosporioides dominated
the endophyte assemblages of AE and XG (abbreviations are
expanded in Table 1), P. capitalensis was dominant in AI, BG, EA, LL,
LR and SH and co-dominat in AE and SA, Phomopsis spp. was
dominant in AC, AM, AO and RM and co-dominant in AI, BG, LR, PP,
RA and RS, Xylaria spp. was dominant in BC, BP, CT, NF, PP and RS
and co-dominant in AM, AO, BC, BP, CT, LL, RM, SH and XG (Table 3).
An ITS sequence analysis of the 16 Phomopsis/Diaporthe isolates
showed that these belonged to 10 different species (Table 2). Dia-
porthe pseudomangiferae was endophytic in the leaves of AC, AM,
AO and CT. D. discoidispora was present in BP, LL, and RM while
D. hongkongensis was isolated from NF and PP. D. longicolla, D.
kyushuensis, Phomopsis heveicola, D. eucalyptorum, D. liquidambaris,
D. perseae and D. tectonae were isolated from the leaves of AI, BC,
BG, LR, SH, SA, and XG respectively. A bootstrap consensus tree
constructed based on maximum likelihood approach showed that
the Phomopsis/Diaporthe isolates could be grouped into several
distinct clades (Fig. 2). Many species of Phomopsis/Diaporthe were
isolated from different mangroves indicating very little host spec-
ificity among the endophytic isolates. We also could not discern any
clusters based on the location from which these isolates were ob-
tained. Statistical analyses revealed that while the number of
endophyte isolates increased with increasing sample size, the
Table 1
Mangrove species of Andaman Islands, India studied for foliar fungal endophytes.
Code Mangrove Plant Family Collection Site Co-ordinates
AE Acanthus ebracteatus Vahl Acanthaceae Shippighat 11
39
0
52.3368
00
N92
44
0
11.04
00
E
AI Acanthus ilicifolius L. Acanthaceae Wright myo 11
47
0
19.0896
00
N92
43
0
34.3884
00
E
AC Aegiceras corniculatum (L.) Blanco Myrsinaceae Corbyn's Cove 11
38
0
40.7976
00
N92
44
0
51.3636
00
E
AM Avicennia marina (Forssk.) Vierh. Avicenniaceae Burmanallah 11
33
0
27.3924
00
N92
43
0
47.3448
00
E
AO Avicennia officinalis L. Avicenniaceae Corbyn's Cove
BC Bruguiera cylindrica (L.) Blume Rhizophoraceae Chidiyatapu 11
30
0
21.9564
00
N92
42
0
6.0948
00
E
BG Bruguiera gymnorhiza (L.) Lam. Rhizophoraceae Burmanallah
BP Bruguiera parviflora (Roxb.) Wight &Arn. exGriff. Rhizophoraceae Shoal Bay 11
53
0
52.53
00
N92
46
0
32.1204
00
E
CT Ceriops tagal (Perr.) C.B. Rob. Rhizophoraceae Manjeri 11
32
0
33.36
00
N92
39
0
8.7588
00
E
EA Excoecaria agallocha L. Euphorbiaceae Burmanallah
LL Lumnitzera littorea (Jack) Voigt Combretaceae Shoal Bay
LR Lumnitzera racemosa Willd. Combretaceae Manjeri
NF Nypa fruticans Wurmb Arecaceae Shippighat
PP Phoenix paludosa Roxb. Arecaceae Shippighat
RA Rhizophora apiculata Blume Rhizophoraceae Burmanallah
RM Rhizophora mucronata Lam. Rhizophoraceae Burmanallah
RS Rhizophora stylosa Griff. Rhizophoraceae Chidiyatapu
SH Scyphiphora hydrophyllacea C.F. Gaertn. Rubiaceae Shoal Bay
SA Sonneratia alba Sm. Lythraceae Wright myo
XG Xylocarpus granatum J. Koenig Meliaceae Burmanallah
T. Rajamani et al. / Fungal Ecology 36 (2018) 109e116 111
numbers of endophyte species (Fig. 3), unique species and single-
tons (Fig. 4) decreased with increasing sample size.
4. Discussion
The leaves of all the mangrove species studied harboured cul-
turable fungal endophytes. In community level investigations, the
sample size should be large enough to inform the diversity of the
organisms studied. The sample size in the present study was
rigorous enough to represent the diversity of foliar endophytes of
the mangrove community existing at the time of sampling. This is
borne out by the observation that the accumulation of endophyte
species, as well as the unique and singleton species among them,
although increasing initially, started to decrease with increasing
sample size (Longino, 2000;Henderson, 2003;Suryanarayanan
et al., 2011). The total CF% of the endophytes (which is also equal
to the total number of isolates since 100 tissue segments were
screened for each mangrove species) was higher than 100% in nine
mangrove species due to the growth of more than one endophyte
species from a tissue segment. This indicated that the density of
colonization of the leaves by endophytes is high.
Leaf endophytes enhance the tolerance of terrestrial host plant
to pathogen (Arnold et al., 2003) and herbivores (Estrada et al.,
2015). Mangrove endophytes have not been investigated for such
a role in biotic stress tolerance of mangroves. Furthermore, as
speculated by Suryanarayanan (2013), dense colonization of leaves
by endophytes could affect photosynthesis negatively by draining
photosynthates or positively by creating localized zones of low
photorespiration in the leaf due to their respiration. This aspect
gains importance as the air in mangrove canopy is low in CO
2
and
its microclimate is different from that of the terrestrial plants due to
tidal inundation (Al-Saidi et al., 2009).
In the present study, species of Colletotrichum, Phomopsis,
Phyllosticta and Xylaria were more commonly isolated as endo-
phytes and were present in different mangrove species. These fungi
have a wide host range as foliar endophytes and have been reported
from mangroves of Hong Kong (Pang et al., 2008), Thailand
(Chaeprasert et al., 2010), Brazil (Wanderley et al., 2012;de Souza
Sebastianes et al., 2013) and China (Li et al., 2016). These fungi as
endophytes are known to have loose plant host affiliation and occur
even in taxonomically unrelated terrestrial plants distributed
throughout the world (Pandey et al., 2003;Murali et al., 2006;
Govinda rajulu et al., 2013;Unterseher et al., 2016). Although, low
host specificity is a rule among several guilds of tropical fungi
including the endophytes (Suryanarayanan, 2011), of particular
Fig. 2. Bootstrap consensus tree based on Maximum Likelihood method for Phomopsis/
Diaporthe isolates obtained in the study. Black squares indicate sequences obtained in
the present study, open squares represent type sequences while open triangles
represent other sequences.
Table 2
Phomopsis/Diaporthe species identified based on ITS-sequences and their GenBank
accession number (Refer Table 1 for host code).
Host Code Isolate GenBank Accession No.
AI Diaporthe longicolla MH371243
AC Diaporthe pseudomangiferae MH371242
AM Diaporthe pseudomangiferae MH371241
AO Diaporthe pseudomangiferae MH371244
BC Diaporthe kyushuensis MH371245
BG Phomopsis heveicola MH371246
BP Diaporthe discoidispora MH371247
CT Diaporthe pseudomangiferae MH371248
LL Diaporthe discoidispora MH371249
LR Diaporthe eucalyptorum MH371250
NF Diaporthe hongkongensis MH371251
PP Diaporthe hongkongensis MH371252
RM Diaporthe discoidispora MH371253
SH Diaporthe liquidambaris MH371255
SA Diaporthe perseae MH371254
XG Diaporthe tectonae MH371256
T. Rajamani et al. / Fungal Ecology 36 (2018) 109e116112
interest is the wide host range of Diaporthe (Phomopsis) spp.
observed in the present study which is indicative of their ecological
success. For instance, in our study, Phomopsis (Diaporthe) species
were isolated from all the mangrove species. Of the 20 isolates from
the 20 mangrove species, 4 (from AE, EA, RA and RS) failed to grow
upon further sub-culturing and the other 16 were taken up for
identification at the species level using ITS sequencing since
morphological characters of this genus are unreliable (Gomes et al.,
2013;Dissanayake et al., 2017). Interestingly we did not observe
any host specificity among the Phomopsis isolates since the same
species were isolated from different mangroves. This further attests
to the loose host affiliation seen among major fungal endophytes,
especially in tropical climates, and might be a major contributing
factor in their extraordinary success as an endophyte in wide and
disparate hosts.
The present survey involving more mangrove species than
earlier studies confirms that leaf endophytes of mangroves are not
unique with reference to their species diversity and frequency of
occurrence when compared to those of terrestrial plants. Mangrove
leaves accumulate salt as they mature (Cram et al., 2002) to levels
which are 3e12 times higher when compared to terrestrial plants
(Dissanayake and Amarasena, 2009). They are also rich in tannins
(Maie et al., 2008) which are inhibitory to fungal growth (Harrison,
1971 ;Dix, 1979). The common foliar endophytes of mangroves are
tolerant of high concentrations of both salt and tannins (Kumaresan
et al., 2002). Selection of fungi with traits to survive in the salt and
tannin-rich leaves of mangroves could be the reason for the wider
ecological amplitude of certain endophyte genera in the mangrove
forest.
Fungi in general, along with bacteria and oomycetes, are known
Table 3
Dominant and Co-dominant endophyte species present in the leaves of mangrove plants of Andaman Islands, India (Refer Table 1 for host code).
Host Code Dominant endophyte Co-dominant endophyte
Name Order Name Order
AE Colletotrichum gloeosporioides Glomerellales Phyllosticta capitalensis Botryosphaeriales
AI Phyllosticta capitalensis Botryosphaeriales Diaporthe longicolla Diaporthales
AC Diaporthe pseudomangiferae Diaporthales Sterile form 4 e
AM Diaporthe pseudomangiferae Diaporthales Nodulisporium sp. 1 Xylariales
AO Diaporthe pseudomangiferae Diaporthales Xylaria sp. 2 Xylariales
BC Xylaria sp. 1 Xylariales Nodulisporium sp. 1 Xylariales
BG Phyllosticta capitalensis Botryosphaeriales Phomopsis heveicola Diaporthales
BP Xylaria sp. 1 Xylariales Nodulisporium sp. 2 Xylariales
CT Xylaria sp. 1 Xylariales Nodulisporium sp. 1 Xylariales
EA Phyllosticta capitalensis Botryosphaeriales Graphium sp. Microascales
LL Phyllosticta capitalensis Botryosphaeriales Xylaria sp. 1 Xylariales
LR Phyllosticta capitalensis Botryosphaeriales Diaporthe eucalyptorum Diaporthales
NF Xylaria sp. 1 Xylariales Penicillium sp. 1 Eurotiales
PP Nodulisporium sp. 1 Xylariales Diaporthe hongkongensis Diaporthales
RA Aspergillus fumigatus Eurotiales Phomposis sp. 2 Diaporthales
RM Diaporthe discoidispora Diaporthales Xylaria sp. 1 Xylariales
RS Xylaria sp. 1 Xylariales Phomposis sp. 1 Diaporthales
SH Phyllosticta capitalensis Botryosphaeriales Xylaria sp. 1 Xylariales
SA Pestalotiopsis sp. Amphisphaeriales Phyllosticta capitalensis Botryosphaeriales
XG Colletotrichum gloeosporioides Glomerellales Xylaria sp. 1 Xylariales
Fig. 3. Species accumulation curve for foliar endophytes isolated from twenty mangrove species. Dotted lines represent 95% confidence interval limits (upper and lower bounds) for
species observed. Data were randomized 100 times for plotting the graph.
T. Rajamani et al. / Fungal Ecology 36 (2018) 109e116 113
to decompose mangrove litter (Kristensen et al., 2008). It is now
established that foliar endophytic fungi remain in fallen leaves,
switch to a saprotrophic mode (Unterseher et al., 2013;Guerreiro
et al., 2017) and, owing to their ability to produce different extra-
cellular enzymes, aid in litter decomposition (Suryanarayanan
et al., 2012). Kumaresan and Suryanarayanan (2002) reported
that the density of colonization of endophytic Glomerella sp. and
Pestalotiopsis sp. in the leaves of the mangrove R. apiculata in-
creases in fallen leaves with time and that these fungi produce
biomass destructuring enzymes indicating their role in mangrove
litter decomposition. Talaromyces stipitatus, a root endophyte in the
mangrove Avicennia marina, elaborates salt-tolerant chitin modi-
fying enzymes (Paranetharan et al., 2018). The specific role of
mangrove endophytes in litter decomposition has to be addressed
to understand their contribution to carbon dynamics in mangrove
ecosystem. Since endophyte association confers salt tolerance in
some plants, (Rodriguez et al., 2008;Khan et al., 2015), it could be
worthwhile to investigate the contribution of endophytes to the
fitness of mangroves.
To conclude, the mangrove ecosystem supports diverse micro-
organisms which perform various functions. The diversity and roles
of archaea (Bhattacharyya et al., 2015) and bacteria (Basak et al.,
2016;Chen et al., 2016) in this ecosystem are well established.
With reference to fungi, only the manglicolous (Sahoo and Dhal,
2009) and mycorrhizal fungi (D’Souza, 2016) have been studied in
detail. Considering the importance of endophytes in enhancing
host plant's fitness and recycling nutrients, this cryptic ecological
group of fungi of the mangroves deserves more attention to get a
holistic view of the mangrove ecosystem.
Acknowledgements
TSS thanks the Principal Chief Conservator of Forests, Andaman
and Nicobar Islands for granting permission to collect leaf samples.
TSS and TR thank the Department Biotechnology, Government of
India for the grant of a research project (BT/PR7026/NDB/39/458/
2013) and JRF Fellowship respectively.
Supplementary data
Supplementary data to this article can be found online at
https://doi.org/10.1016/j.funeco.2018.09.007.
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