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IDENTIFICATION AND DISTRIBUTION OF ARBUSCULAR MYCORRHIZAL SPORES IN SELECTED PLANT
ROOTS AND THEIR SURROUNDING SOIL
Tiang Bi Ren
(39159)
QK Bachelor of Science with Honours604.2
(Resource Biotechnology) M92 2015T55l
2015
Pusat Khidmat Maklumat Akaclem ik UN IVER ITI MA LAYSIA SARAWA '
Identification and Distribution of Arbuscular Mycorrhizal Spores in Selected Plant Roots and Their Surrounding Soil
Tiang Bi Ren (39159)
This project is submitted in fulfillment of the requirement for the Degree of Bachelor of
Science with Honours
(Resource Biotechnology)
Supervisor: Dr. Samuel Lihan Co-supervisor: Dr. Rebicca Edward
Resource Biotechnology Department of Molecular Biology
Faculty of Resource Science and Technology Universiti Malaysia Sarawak
I.
i
ACKNOWLEDGEMENT
First and foremost, I would like to express my fullest gratitude to my research supervisor,
Dr. Samuel Lihan, in the process of completion in this project. I am extremely grateful to
my supervisor for sharing his expertise, valuable guidance and encouragements which are
vital for me to complete my research. Without his valuable time and patience, I am
certainly that this research work could not be carried out smoothly and effectively.
Next, I would also like to express my sincere appreciation to Rakiya Abdullahi, the
postgraduate student of Bacteriology Laboratory. I am thankful for her full assistance,
valuable advices, and concerns during my research work in the Bacteriology Laboratory.
Without her fullest help, it will be hard for me to accomplish my experiment well. Thus, I
sincerely felt grateful for her help in my work .
I would also like to take this opportunity to show my gratitude to my family
members especially my parents for their constant support, encouragement and attention
towards me for me to complete my research work. With an unceasing support from my
family, I was able to complete my research project smoothly.
On top of that, I would like to extend my gratefulness to all my colleagues in
Bacteriology Laboratory. I am thankful for having colleagues who always share their
knowledge and ~dvice to me in my project work.
Last but not least, I would like to record my sincere gratitude to everyone, who either
directly or indirectly has lent their hands in guiding and making my research work a
success .
'.
UNIVERSITI MALAYSIA SARA WAK
Grade:
Please tick (.J) Fina f Year Project Report [Z] Masters D PhD D
DECLARATION OF ORIGINAL WORK
This declaration is made on the .... JQ~~......day of.....~~.~.~ ....2015.
Student's Declaration:
I, Tiang Bi Ren, 39159, ofFaculty of Resource Science and Technology hereby declare that the work entitled
"Identifiction and Distribution of Arbuscular Mycorrhizal Spores in Selected Plant Roots and Their
Surrounding Soil" is my original work. r have not copied from any other students' work or from any other
sources except where due reference or acknowledgement is made explicitly in the text, nor has any part been
written for me by another person.
TI~ 81 RW (3~\r~) Date submitted Name of the student (Matric No.)
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Mycorrhizal Spore~ in Selected Plant Roots and Their Surrounding Soil" was prepared by the above named
student, and was submitted to the "FACULTY" as a * partiaVfull fultillment for the conferment of Bachelor
of Science with Honours, and the aforementioned work, to the best of my knowledge, is the said student's
work.
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(Name of the supervisor)
I declare that Project/Thesis is classi fied as (Please tick (~)):
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research was done)*
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Pusat hicfmat Makfumat Akadem ik UNIVER. IT I . A AYS A ARAWAK
TABLE OF CONTENTS
ACKNOWLEDGEMENT
DECLARATION II
T ABLE OF CONTENTS
ABSTRACT
IV
LIST OF ABBREVIATIONS VII
LIST OF FIGURES VIII
LIST OF TABLES IX
1.0 INTRODUCTION 2.
2.0 LITERATURE REVIEW 4
2.1 Mycorrhizae 4
2.2 Arbuscular Mycorrhizae Fungi (AMF) 4
2.2.1 History of Arbuscular Mycorrhiza Fungi 4
2.2.2 Morphological Features of AM fungi 5
2.3 Arbuscular Mycorrhiza Fungi Symbiosis 7
2.4 Benefits of Arbuscular Mycorrhiza Fungi 8 ..
2.4.1 Increased Nutrient Uptake in Plants 8
2.4.2 Bio-control Agent 8
2.4.3 Potential as Bio-fertilizer 9
2.4.4 Drought Tolerance 9
2.4.5 Salt Tolerance 10
IV
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2.5 Studies on the AM Fungi Diversity 12
2.6 Studies on the Soil Physicochemical Properties on Colonization of AM fungi 14
3.0 MATERIALS AND METHODS 15
3.1 Collection of Soil and Root Samples 15
3.2 Observation of AM Fungi Spores in Plant Root Samples 16
3.3 Isolation of AM Fungi Spores 16
3.3.1 Wet Sieving and Decanting Technique 16
3.3.2 Sucrose Density Gradient Centrifugation Technique 18
3.4 Quantification of AM fungi Spores 19
3.5 Staining of AM Fungi Roots 19
3.6 Assessment of AM Fungi Root Colonization 20
3.7 Identification of AM fungi Spores 21
3.8 Soil Physicochemical Analysis 22
3.8.1 Physical Analysis of Soil Samples 22
3.8.2 Chemical Analysis of Soil Samples 25
3.9 Statistical Analysis 25
4.0 RESULTS 26
4.1 Observation of AM Fungi Spores 26
4.2 Quantification of AM Fungi Spore 27
4.3 Estimation of AM Fungi Root Colonization 28
4.4 Identification of AM Fungi Spores 29
v
4.5 Physicochemical AnaLysis of Soil Samples 33
4.5.1 Physical Analysis of Soil Samples 33
4.5.2 Chemical Analysis of Soil Samples 34
4.6 Statistical Analysis 35
5.0 DISCUSSION 36
CONCLUSION 43
REFERENCES 45
APPENDICES 50
"
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LIST OF ABBREVIATIONS
AM Arbuscular Mycorrhiza
AMF Arbuscular Mycorrhiza Fungi
INVAM International Culture Collection of Vesicular and Arbuscular Mycorrhizal
Fungi
PVP Polyvinyl Pyrrolidone
SPSS Statistical Package for Social Sciences
J.1m micrometer
VAM Vesicular Arbuscular M ycorrhiza
."
VII
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LIST OF FIGURES
Figure 1 Main structures of AM fungi 6
Figure 2 Sampling sites for plants 15
Figure 3 Sieves used for wet sieving and decanting method 17
Figure 4 Sievings collected in different Petri dishes 17
Figure 5 Flow diagram for "Feel Method" 24
Figure 6 AM spores observed under microscope at magnification of lOOX 26
Figure 7 Glomus spp. 30
Figure 8 Rhizophagus spp. 30
Figure 9 Acaulospora spp. 31
Figure 10 Funnel({ormis spp. 31
Figure 11 Isolated types of AM spores 32
VIII
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Table I
Table 2
Table 3
Table 4
Table 5
Table 6
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LIST OF TABLES
Enumeration of spores of AM fungi per gram of soil samples 27
Percentage of root colonization of AM fungi in soil samples 28
Identification of isolated AM fungi spores 29
Characteristics of soil texture analysis of plant samples 33
Reading of pH meter from soil samples 34
Pearson correlation analysis of soil pH and colonization rate of AM fungi 35
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Identification and Distribution of Arbuscular Mycorrhizal Spores in Selected Plant Roots and Their Surrounding Soil
Tiang Bi Ren (39159)
Resource Biotechnology Programme Department of Molecular Biology
Faculty of Resource Science and Technology University Malaysia Sarawak
ABSTRACT
Arbuscular mycorrhizas fungi (AMF) possess great potential in ecosystem especially in agricultural system as they can contribute towards the sustainability of the system. AMF have the ability to increase nutrient uptake, alleviate environmental stresses, and potential as bio-fertilizer. Thus, the aim of this project was to isolate, characterize and identify morphologically types of AMF present in selected plants sampled around Kota Samarahan which consists of Cassava, Carica papaya, Cymbopogon, and Pandanus ammyllifolius, quantification of AMF spores, and analysis of soil physicochemical properties towards colonization of AMF. Isolation process of AMF spores was carried out using wet sieving and decanting method and spores were characterized morphologically. From result obtained, genera of AMF isolated consisted of Acaulospora, Funneliformis, Glomus, and Rhizophagus whereby genus Glomus was found dominant among all plant samples. It also showed that soil texture and pH affect the colonization rate of AMF. Cassava recorded the highest colonization rate of AMF with 20% whereas Cymbopogon recorded lowest AMF colonization rate of 10% only. From this study, AMF spores were successfully isolated from different plant roots and characterized morphologically. Soil texture and soil pH were found to affect the colonization rate of AMF in plants.
Key words: Arbuscular mycorrhiza fungi (AM F), isolation, physicochemical, colonization
ABSTRAK
Kulat Arbuskel Mikoriza (KAM) memiliki potensi yang besar dalam ekosistem terutamanya dalam bidang pertanian kerana KAM dapat meyumbang kepada kemampanan ekosistem. KAM mempunyai kemampuan untuk meningkatkan pengambilan nutrisi,penguranagan tekanan alam sekitar, serta potensi sebagai bio-baja. Justeru, objektif projek ini adalah un/uk mengasingkan, mengcirikan dan mengenalpasti spora KAM secara m01jologi dalam tumbuhan yang disampel sekilar Kota Samarahan yang terdiri daripada Cassava, Carica papaya, Cymbopogon, dan Pandanus amaryllifolius, pengkuantifikasian spora KAM dan analisis faktor jizikokimia /anah terlradap kolonisasi KAM. Proses isolasi spora KAM dijalankan dengan menggunakan teknik pengayakan basah dan dekantasi dan spora KAM diidentifikasi secm'a morfologi. Daripada hasil kepulusan, genus KAM yang diperoleh terdiri daripada genus Acaulospora, Funneliformis, Glomus dan Rhizophagus dan genus Glomus mendominasi dalam semua tumbuhan. Kajian ini juga menunjukkan tekstltr tanah dan pH mempengaruhi kadar kolonisasi KAM. Cassava merekodkan kadar kolonisasi yang tertinggi dengan 20 peratus manakala Cymbopogon merekodkan kadar kolonisasi yang terendah iaitu sebanyak J0 peratus sahaja. Daripada kajian ini, spora KAM Berjaya diisolasi daripada pelbagai akar tumbuhan, dan dikenalpasti secara morfologi. Tekstur tanah dan pH tanah didapati mempengaruhi kadar kolonisasi AMF dalam tumbuhan.
Kata kunci: Kulat Arbuskel Mikoriza (KAM), isolasi, fizikokimia, kolonisasi
1.0 INTRODUCTION
Various kinds of microorganisms are present in the soil whereby each of these
microorganisms plays an important role in diverse physiological events in the soil
environment. One of these microorganisms that are involved in these activities IS
mycorrhiza fungi. Mycorrhiza is a special interaction between two eukaryotes which
comprises of an obligate biotrophic fungus and a host plant whereby both associates obtain
benefits from the mutual relationship (Bonfante & Genre, 2008). These mycorrhiza fungi
form a symbiotic relationship whereby the plant supply sugars to the fungi and in return
the fungi supply phosphorus to the plant cells. There are six major groups of mycorrhizas
which comprises of ectomycorrhizae, endomycorrhizae, ectendomycorrhizae, arbutoid
mycorrhizae, monotropoid mycorrhizae and orchid mycorrhizae (Harley & Smith, 1983).
Amongst diverse types of mycorrhizaes, Arbuscular Mycorrhiza (AM) fungi is one
of the commonly and recurring endomycorrhiza around the world (Shanna & Yadav,
20 13). The most distinct char acteristic of AM fungi is the growth of arbuscules which are
highly branched inside the root cortical cells. The fungi will grow between cortical cells
originally and then penetrate the host cell and subsequently grows in the cells fonning new
sections which contain high molecular complexity materials that are enveloped by the host
cell.
Presently, AM fungi is one of the enctomycorrhiza which are being studied
intensively by researchers as AM fungi exists in most natural ecosystem and agricultural
field and play pivotal role in the growth, health and productivity of plants (Kanchana &
Gupta, 2012). The ability of AM fungi to fonn close associations with most species of
plants and significantly improving the uptake of mineral nutrients in exchange of
photosynthetates, decrease stresses caused by biotic and abiotic factors and huge potential
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as bio-fertilizer have greatly drawn attention of researchers to study it intensively for a
productive agricultural practices.
AM fungi have diversity of species and genera and their composition are greatly
different between every plant species. According to Bever et al. (200 1), the understanding
of roles of each individual AM fungi species is comparatively inadequate even though
records of ecological benefits by AM fungi in overall are plentiful. Various researches
indicated that the growth of plant is influenced by the corresponding fungal species and
particular plant involved (Bever et al., 200 1).
However, there were not much researches conducted on the status of AMF in
Malaysia. Therefore, this study is conducted to investigate the type of indigenous species
of AM fungi that are present in various plants which are tapioca plant, papaya, lemongrass
and pandan leaves that sampled around Kota Samarahan, Sarawak.
The objectives of this study being conducted are:
• To isolate and quantify Arbuscular Mycorrhiza (AM) fungi spores from different
plant roots and their surrounding soil;
• To characterize morphologically isolated Arbuscular Mycorrhiza (AM) fungi
spores present in the sample plants;
• To study the effect of soil physicochemical properties towards the colonization of
Arbuscular Mycorrhiza (AM) fungi.
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2.0 LITERATURE REVIEW
2.1 Mycorrhizae
Mycorrhizae fungi are found to be occurring abundantly in all natural ecosystems and play
a vital role in these ecosystems. According to a study done by Peyronel et al. (1969) ,
earliest classification of mycorrhizae was based on the comparative location .of fungi in the
roots whereby these mycorrhizaes was divided into endomycorrhizae, ectomycorrhizae,
and ectendomycorrhizae. However, these classifications were not sufficient to determine
the variety of associations involving mycorrhiza. Thus, from the study done by Harley and
Smith (1983), commonly accepted classifications of mycorrhiza were proposed by them
which divided the mycorrhiza into six groups that consists of endomycorrhiza,
ectomycorrhiza, ectendomycorrhiza, arbutoid mycorrhiza, monotropoid mycorrhiza and
orchid mycorrhiza.
2.2 Arbuscular Mycorrhizae Fungi (AMF)
2.2.1 History of Arbuscular Mycorrhiza Fungi
Arbuscular mycorrhiza fungi are known as obligate symbiotic fungi which can be found in
most species of terrestrial plants. AM fungi belongs to the phylum Glomeromycota which
includes eleven families and twenty-five genera of species are a key component in the soil
microbiota and Signify the most significant terrestri~l symbiosis (Bumi et al., 2011).
According to Brundrett (2004), AM fungi were found to evolve from 460 million
years ago from the records of fossils found from Ordovician Age. From these records, it
proved that AM fungi play an important role in the colonization of most terrestrial plants in
the natural ecosystems. According to Strack et al. (2003), the term "mycorrhiza" originated
from Greek word whereby ' myces ' means fungus and 'rhiza' means root and this term was
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usat Khidmpt Makhmlat Akad mil< UN1VERSITI MALAY IA SARAWAK
jproposed in 1885 by Bernhardt Frank. Arbuscular mycorrhiza was named so due to a
prevalent characteristic whereby they have a unique branching arrangement called
arbuscules growing inside the cortical cells of host plant roots. The formation of arbuscules
greatly increases the contact area between the plant and the fungus . The exchange of
nutrients such as phosphorus, zinc and copper from the soil to the plant took place in the
arbuscules with the aid of AM fungi and in return, the plant provides carbohydrate to the
fungi.
2.2.2 Morphological Features of AM fungi
AM fungi is made up of three major constituents which comprises of the root itself where
the root supplied carbon in the form of sugars to the fungi; the formation of arbuscules
within the cortical cells of the plant root that enables the contact between the plant
cytoplasm and the fungus and also the structure of extraradical hyphae which help in
nutrients uptake (Smith & Read, 2008) . •
Spores of AM fungi formed on the subtending hyphae as swellings which occurred
either in the soil or in the roots of host plant. These spores contain storage lipids which
function as energy source for pre-symbiotic growth. According to Hosny et al. (1998), AM
fungi spores are found to comprise of cytoplasm and contain abundant nuclei which vary
from 576 nuclei and can reach up to 35000 nuclei in different species of plants.
Blaszkowski et al. (2002) stated that nearly all sp@res of AM fungi devetoped thick walls
which can have more than one layer. However, the color, morphology and the composition
of the spores differ dependent on the species of the AM fungi . Variation in these
characteristics caused the size of the spores to be varied greatly between the species which
can be from 20 J!m to 100 J!m (Dalpe et aI., 2005).
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According to Bago et al. (1998), arbuscules are structures that are tree-shape like
and fonned by repeated dichotomous branching inside the cell wall of root cortical cell of
host plant. Arbuscules act as an indicator of active mycorrhiza in the soil. Arbuscules
function as the main site for exchange of nutrients and signaling exchange between a host
plant and a fungus (Parniske, 2008).
Dalpe et al. (2005) reported that vesicles of AM fungi were formed from the
swellings of intraradical hyphae and it is filled with lipids and glycolipids which are
necessary for growth of host plant. Vesicles are fonned to collect storage products in many
vesicular arbuscular mycorrhizal (V AM) relationships. On top of that, extensively fonned
extraradical mycelium in the fungi helps in the exchange of nutrients between the roots and
the fungi (Aggangan et al., 2011). Figure 1 showed the main structures that were
associated with AM fungi in plant root.
{ {
matrical' pore
lr
r t: cort x
t: cpidcrJ:'T1 i
h bae
Figure 1: Main structures of AM fungi (Moore, 2011).
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2.3 Arbuscular Mycorrhiza Fungi Symbiosis
Smith and Read (2008) reported that various researches conducted by scientists indicated
that many plants do not interact directly with the soil environment; instead, these plants
interact indirectly with the soil environment through the arbuscular mycorrhiza fungi .
Klironomos (2003) stated that AM fungi possessed the capability of forming symbiosis
with plants making the Glomeromycota being characterized as a generalist organism in
most plants.
The mechanism of converting phosphate that passes through fungal membrane into
polyphosphate which are bounded within the vesicles and transported back through the
hyphae to the host plant by the AM fungi enabled the host plant's phosphate necessity to
be filled up to ninety percent and thus increases the phosphate uptake significantly (van der
Heijden et al., 2008). Extraradical myceliums that are present in AM fungi functions as an
extension of roots for the host plant which efficiently exploit available resources for the
plant by extending its mycelium to the surface of the soil (Ollson et ai, 2002). Aggangan et
al. (2011) stated that extraradical myceliums which are extensively formed in the fungi
help in the exchange of nutrients between the plant roots and the fungi.
Finlay (2008) stated that the hyphae of AM fungi were able to access and release
nutrients that were physically or physiologically inaccessible to the roots of the plant
" which increases the uptake of nutrients in plants. The hyphae of AM fungi are able to
obtain nutrients in the soil through the accelerated process of decomposition and lysing of
soil microbes (Ollson et al., 2002).
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2.4 Benefits of Arbuscular Mycorrhiza Fungi
2.4.1 Increased Nutrient Uptake in Plants
In a study done by Naher et al. (2013) on inoculated AM plants, AM fungi are being
reported to help to increase the uptake of nutrients such as phosphorus and zinc compared
to non-inoculated plants. AM fungi are ubiquitous and fonn a symbiotic relationship with
the roots of most terrestrial plant on the Earth. The association between AM fungi and
plant benefits the plant nutrition, growth and survival due to their enhanced exploitation of
soil nutrients.
From a study done by Al-Karaki and Al-Raddad (as cited in Naher et al., 2013),
mineral contents in wheat plants that are inoculated with AM fungi are found to be higher
compared to non-inoculated wheat plants. Besides, Wu et al. (2011) conducted a study on
the nutrient uptake in peach plants that were inoculated with AM fungi with non
inoculated peach plants. From the result 'obtained, it showed that mycorrhizal inoculation
increased the nutrient uptake and growth perfonnance of peach seedlings. It also showed
that Glomus mossea exhibited best mycorrhizal efficiency on the growth and nutrient
acquisition ofpeach seedlings.
2.4.2 Bio-control Agent
AM fungi are found to be able to activate and increase the defense level of plants against
soil-borne pathogens. Al-Askar and Rashad reported that AM fungi playa pivotal role in
protecting bean plant against Fusarium solani (as cited in Naher et al., 2013). According to
Naher et al. (2013), a number of findings showed that mycorrhizal inoculation directly or
indirectly increased the plant defense mechanism against pathogens.
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In another study done by Akhtar and Siddiqui (2007), they reported that the
establishments of AM fungi in plant roots have been shown to reduce damages caused by
soil-borne plant pathogens with enhancement of resistance in mycorrhizal plants. In a
study done by Vailleau et al. (2007), they conducted experiment on tomato plants which
was inoculated with AM fungi . Their result showed positive result whereby the inoculated
tomato plants reduce the infestation of Ralstonia solanacearum which is a causal of
bacteria wilt disease in crop plant.
2.4.3 Potential as Bio-fertilizer
According to Sadhana (2014), bio-fertilizer is organic substances whereby it makes use of
the microorganisms to increase the fertility of soil and AM fungi are among these
microorganisms which play important role in the application ofbio-fertilizer. AM fungi are
found to enhance the growth and productivity of crops when applied as bio-fertilizer to the
crops. Sadhana (2014) stated that the use of AM fungi as bio-fertilizer do not cause any
pollution and are environment-friendly for agricultural practice.
Bhat et al. (20 I 0) studied the effect of Rhizobium and V AM fungi on green grain
(Vigna radiate L. wilczek) under temperate conditions. From the result obtained in the
study, there was a significant effect of Rhizobium and V AM on the level of nitrogen levels
in grain. The nodulation, nitrogen, phosphorus and calcium content in the grain and also
crude protein content increases significantly.
2.4.4 Drought Tolerance
According to various researches done, AM fungi were able to protect plants from drought
stress and its damaging results. Drought stress was thought as one of the most essential
abiotic factor that will limit the growth of plants (Porcel & Luiz-Lozano, 2004). From the
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study done by Porcel and Luiz-Lozano (2004) on the tolerance of drought in soybean
plants, they found out that soybean plants that were inoculated with AM fungi were
protected against drought compared to non-inoculated AM fungi soybean plants. Their
result showed that AM-inoculated plants have significantly higher shoot-biomass
production and leaf water potential than non-inoculated plants.
According to Jeffries and Barea (2012), AM fungi symbiosis often resulted in the
altered rates of the water movement into, through and also out of the host plant, with
positive consequences for the physiology of the plant and tissue hydration. Accordingly,
AM fungi symbiosis able to protect crop plants against the damaging effects of the water
deficit in the plant and that the AM fungi contribution to plant drought tolerance resulting
from a combination of physical, nutritional and also cellular effect of the plant.
2.4.5 Salt Tolerance
According to Abdel Latef and Miransan (2014), salt stress was a huge threat that
unfavorably hanned the productivity and growth of plant. Evelin et al. (2009) stated that
there were various researches done by scientists on the mechanisms that are involved in the
alleviation of salt stress by AM fungi and the significant role played by AM fungi in these
stress. There are various mechanisms employed by AM fungi which comprises of
biochemical mechanism, physiological and morecular mechanism to reduce salt stress in
plant (Evelin et al.. 2009). Abdel Latef and Miransari (2014) stated that AM fungi help in
the tolerance of salt in plant by various mechanisms such as increasing nutrient uptake in
plant, manufacturing growth honnone in plant, and improving the activity of
photosynthesis and usage of water efficiency in the plant.
Estrada et al. (2013) conducted a study on the salt tolerance efficiency in AM fungi
inoculated maize plant. In the study, Estrada et al. (2013) researched whether indigenous
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AM fungi that were isolated from location with salinity problem would help the maize
plant to reduce effects of salt stress better than non-inoculated AM fungi maize plants.
From their findings, they concluded that maize plant that were inoculated with native AM
fungi showed higher shoot dry biomass at all levels of salinity. They also stated that
inoculated maize plant displayed an increasing potassium ion (K+) and reduced sodium ion
(Na+) buildup compared to non-mycorrhizal plants.
In another study done by Yang et al. (2014), they researched on the salt tolerance
response in AM fungi inoculated apple seedlings. They conducted this study to investigate
the reaction of apple seedlings which were inoculated with AM fungi under various levels
of salinity stress. From the result obtained, it showed that apple seedlings that were
inoculated with AM fungi displayed a better tolerance towards salt stress and had a better
growth compared to non-inoculated apple seedlings.
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2.5 tudies on the AM Fungi Diversity
Symanczik et al. (2014) conducted a research on the occurrence of AM fungi in Arabian
Peninsula. According to the study, they reported on the desert habituated AM fungi found
in the Arabian Peninsula. Symanczik et al. (2014) were able to successfully isolate and
recorded few species of AM fungi from the whole Arabian Peninsula for the very first time.
As these isolates were from extremely dry region, these isolated AM fungi were thought as
an asset to conserve the biodiversity in the desert area especially in the region of Arabian
Penin ula.
In another study done by Muthuraj et al. (2014), they researched on the diversity
existence of AM fungi in forty-six medicinal plants in India. From ~he study, Muthuraj et
al. (2014) were able to isolate 30 AM fungal spores from four genera which are
AClllospora, Gigaspora, Glomus, and Scutellospora and characterized them
morphologically. The study conducted showed that AM fungal symbiosis were found in
various medicinal plants and had great influence on the host plant. This made AM fungi an
important microorganism in the natural ecosystem environment.
Shanna and Yadav (2013) studied on the occurrence of AM fungi in the local
barley field. From the study done, they perfoIm isolation of AM fungi spores from the
local barley field and able to isolate various species of AM fungi from few genera which
mainly comprised of Glomus, Gigaspora, and SClitellospora fOIm the barley field . Based
on the result obtained, ShaIma and Yadav (2013) found out that the local barley fields
which contain AM fungi had a better growth compared to fields that lacked of AM fungi
associations.
On top of that, from another study conducted by Nasrullah et al. (2010), they
studied on the occurrence of AM fungi in the wheat-maize cropping system in Pakistan.
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Various species of AM fungi were successfully isolated from wheat and being
characterized morphologically to identify the species of AM fungi present. From the study
done, they also conclude that the rate of the root infection and density of infection by AM
fungi were influenced by type of soil and locations of plants under different agrological
conditions.
Khades and Rodrigues (2009) researched on the existence of AM fungi in six
varietie of Carica papaya L. in a tropical agro-based ecosystem. From the result obtained,
Khades and Rodrigues managed to document important association of AM fungi with six
varieties of Carica papaya L. They concluded that AM fungi symbiosis between the host
plant and the fungi were controlled by various edaphic factors whereby these factors
directly influenced the enumeration of species associated with papaya varieties from the
agro-based ecosystem in various places .
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