**Abstract**

Bio-fertilizers based on mycorrhizal fungi represent a natural way to enrich the soil in respect of environmental balance. Arbuscular mycorrhizal fungi (AMF) are the most common symbiotic association between terrestrial plants and microorganisms, which are known to improve plants development and growth, especially under stress conditions. The potential for application of AMF in agricultures is an agro-ecological approach to allow better use of soil nutrient reserves. That receives increasing consideration for their prospective application for sustainable agriculture. The present chapter aims to highlight the agro-industrial strategy of AMF bio-fertilizers production explaining agronomics, ecological and economic approaches and benefits. This study aims to focus on the importance of production of bio-fertilizers based on indigenous AMF strains and their role in improving soils enrichment, which will subsequently lead to improved production and agricultural yields on degraded arid soils.

**Keywords:** degraded areas, native inocula, industrial production strategies, agro-economic benefits, conventional method

## **1. Introduction**

Soils are considered as a dynamic system that contains varieties of microorganisms such as bacteria, actinomycetes, and fungi [1]. According to this richness in microorganisms, the eco-biological value of soil is considered. Whereas, maintaining this favorable soil microflora is very important for soil sustainability [2].

In the other hand, arid lands constitute about 35% of world land areas and are characterized by rainfall insufficiency, higher temperatures and evapotranspiration, lower humidity, and a general rareness of vegetation cover [3]. In return, a large mass of world's population lives in these areas, which it is imperative to nourish them. They practice livestock grazing and irrigated agriculture that they try to modernize in order to obtain the best yield. However, the agricultural techniques used in recent decades (use of large quantities of chemical inputs, soil compaction, etc.) which have caused in addition to soil degradation the decrease or even elimination of certain beneficial microorganisms from most cultivated soils,

which has contributed to the loss of productivity of these soils [4]. This destitution requires regular additions in order to revitalize the soil and restore its productivity [2]. But what type of fertility for the soil? In agronomy, the notion of fertilization includes application of various chemicals products such as NPK chemical formulation, pesticides and herbicides, which further degrade the soil and reduce their duration [5]. In fact, modern agriculture are based on heavy usage of chemical fertilizers and harmful pesticides on the crops, with destruction of sustainability of the agricultural systems, cost of cultivation soared at a high rate, income of farmers stagnated and food security and safety became an intimidating challenge with considerable reduction in soil health [6]. In the best of cases where there is an interest in ecological stability, animal and plant waste is applied to fertilize the soils [5]. Recently bio-fertilizers notion begins to emerge. Bio-fertilizers are biological fertilizers based on symbiotic microorganisms. They are mainly divided into two groups: bio-fertilizers based on symbiotic bacteria and bio-fertilizers based on mycorrhizal fungi [7].

Bio-fertilizers are biological fertilizers based on plant symbiotic microorganisms, they are defined as a substance composed of living microorganisms which when applied to seed, plant surfaces, or soil colonizes the rhizosphere or the interior of the plant and promotes growth by increasing the availability of primary nutrients to the host plant [6]. Usually, the bio-fertilizers are mainly divided into two groups: bio-fertilizers based on symbiotic bacteria and bio-fertilizers based on mycorrhizal fungi. Moreover, the presence in nature of bacteria solubilizing mineral elements is exploited; they are cultivated and used as a bio-fertilizer [4]. Furthermore, mycorrhizal fungi bio-fertilizers are divided on two types depending on the fungus itself; there are bio-fertilizers based on ectomycorrhizal fungi and bio-fertilizers based on arbuscular mycorrhizal fungi. Arbuscular mycorrhizal fungi (AMF) promote a significant increase of the area of root absorption of plants colonized, maximizing the use of water and nutrients [8, 9]. These symbiotic fungi enhance plant resistance to water stress, to high temperatures, improve resistance to conditions of toxicity and acidity of soil and to divers' type of pathogens [8]. In addition to soil stabilization in the form of aggregates [9]. AMF are known for their positive effects on phosphorus assimilation by the mineralization of organic phosphorus and solubilization of insoluble phosphorus [10]. In spite of their potential and benefits, the large-scale use of AMFs is still restricted, mainly due to the deficiency of availability of inoculant in high quantities, low cost and high quality, besides the lack of practicality of inoculation in the field [9, 11]. Their efficiency is also questioned by some authors [12, 13], who claim that AMF indigenous community promotes greater root colonization than the addition of commercial inoculants. In this context, the present study, aims to lift the veil on bio-fertilizers based on arbuscular mycorrhizal fungi to ameliorate agriculture in arid lands, their agro-ecological roles, technic of production and the challenges of possibility of installing a bio-fertilizer production unit in these areas.

## **2. Importance of arbuscular mycorrhizal fungi bio-fertilizers**

Arbuscular mycorrhizas are the most common underground mutualistic symbiosis relationship [8]. They are considered as obligate biotrophic organisms that live in the metabolically active roots of terrestrial vascular plants, epiphytes, rhizoids and stems of bryophytes [1–8, 14]. Studies showed that AMF exists 460 million years before first plants originated [2, 15]. They form a mutualistic symbiosis between AMF, belonging to the Glomeromycotina sub-phylum, and 80%

**79**

**AMF species**

Glomus spp. *Rhizophagus intraradices*, *Funneliformis mosseae*

Orchard grass (*Dactylis glomerata*)

*Ocimum basilicum*

*Tamarix articulata*

Indigenous formulation Commercial

Heavy metals

Improved plant biomass causing

Yong et al. [19]

positive impact on photosynthesis and

macronutrient acquisition

Improvement of plant dry weight,

Meglouli et al. [20]

bacterial, archaeal OUT 's and bacterial

diversity

pollution

formulation

Commercial formulation

Soil Salinity

*Glomus deserticola*

Mix of height AMF species originating from saline soils

*Rhizophagus intraradices*

*Septoglomus constrictum*,

Alfalfa (*Medicago sativa* L.) and

Indigenous

Dioxin/furan

polluted soils

inoculum

tall fescue (*Festuca arundinacea*

Schreb

*Triticum aestivum*. *Orvantis* and

Commercial

Biotic stress:

Protection against pathogen and reduction

Mustapha et al. [21]

Oïdium *Blumeria* 

of infection

strain multiplied

Commercial

*graminis*

formulation

*Lord*

*Claroideoglomus lamellosum*, *F.* 

*geosporum*, and *F. mosseae*

*Rhizophagus irregularis, Funneliformis* 

*mosseae*

**Table 1.**

*Impact of AMF bio-fertilizers to alleviate biotic and abiotic stress.*

Black locust (*Robinia* 

*pseudoacacia*)

Tomato *Solanum hypersicum*

Commercial formulation

Drought

**Plant**

**Bio-fertilizers Nature**

**Stress type**

**Mechanism used**

Improving water and nutrient absorption

Improved water content

Plant enhancement and alleviation of soil salinity

Improving plant biomasses, water and nutrient absorption

Kyriazopoulos et al. [17] ElHindi et al. [18]

Bencherif et al. [13]

Kuswandi and Sugiyarto [16]

**References**

*Native Arbuscular Mycorrhizal Fungi and Agro-Industries in Arid Lands…*

*DOI: http://dx.doi.org/10.5772/intechopen.94084*


#### *Native Arbuscular Mycorrhizal Fungi and Agro-Industries in Arid Lands… DOI: http://dx.doi.org/10.5772/intechopen.94084*

*Mycorrhizal Fungi - Utilization in Agriculture and Forestry*

mycorrhizal fungi [7].

which has contributed to the loss of productivity of these soils [4]. This destitution requires regular additions in order to revitalize the soil and restore its productivity [2]. But what type of fertility for the soil? In agronomy, the notion of fertilization includes application of various chemicals products such as NPK chemical formulation, pesticides and herbicides, which further degrade the soil and reduce their duration [5]. In fact, modern agriculture are based on heavy usage of chemical fertilizers and harmful pesticides on the crops, with destruction of sustainability of the agricultural systems, cost of cultivation soared at a high rate, income of farmers stagnated and food security and safety became an intimidating challenge with considerable reduction in soil health [6]. In the best of cases where there is an interest in ecological stability, animal and plant waste is applied to fertilize the soils [5]. Recently bio-fertilizers notion begins to emerge. Bio-fertilizers are biological fertilizers based on symbiotic microorganisms. They are mainly divided into two groups: bio-fertilizers based on symbiotic bacteria and bio-fertilizers based on

Bio-fertilizers are biological fertilizers based on plant symbiotic microorganisms, they are defined as a substance composed of living microorganisms which when applied to seed, plant surfaces, or soil colonizes the rhizosphere or the interior of the plant and promotes growth by increasing the availability of primary nutrients to the host plant [6]. Usually, the bio-fertilizers are mainly divided into two groups: bio-fertilizers based on symbiotic bacteria and bio-fertilizers based on mycorrhizal fungi. Moreover, the presence in nature of bacteria solubilizing mineral elements is exploited; they are cultivated and used as a bio-fertilizer [4]. Furthermore, mycorrhizal fungi bio-fertilizers are divided on two types depending on the fungus itself; there are bio-fertilizers based on ectomycorrhizal fungi and bio-fertilizers based on arbuscular mycorrhizal fungi. Arbuscular mycorrhizal fungi (AMF) promote a significant increase of the area of root absorption of plants colonized, maximizing the use of water and nutrients [8, 9]. These symbiotic fungi enhance plant resistance to water stress, to high temperatures, improve resistance to conditions of toxicity and acidity of soil and to divers' type of pathogens [8]. In addition to soil stabilization in the form of aggregates [9]. AMF are known for their positive effects on phosphorus assimilation by the mineralization of organic phosphorus and solubilization of insoluble phosphorus [10]. In spite of their potential and benefits, the large-scale use of AMFs is still restricted, mainly due to the deficiency of availability of inoculant in high quantities, low cost and high quality, besides the lack of practicality of inoculation in the field [9, 11]. Their efficiency is also questioned by some authors [12, 13], who claim that AMF indigenous community promotes greater root colonization than the addition of commercial inoculants. In this context, the present study, aims to lift the veil on bio-fertilizers based on arbuscular mycorrhizal fungi to ameliorate agriculture in arid lands, their agro-ecological roles, technic of production and the challenges of possibility of installing a bio-fertilizer production unit in

**2. Importance of arbuscular mycorrhizal fungi bio-fertilizers**

Arbuscular mycorrhizas are the most common underground mutualistic symbiosis relationship [8]. They are considered as obligate biotrophic organisms that live in the metabolically active roots of terrestrial vascular plants, epiphytes, rhizoids and stems of bryophytes [1–8, 14]. Studies showed that AMF exists 460 million years before first plants originated [2, 15]. They form a mutualistic symbiosis between AMF, belonging to the Glomeromycotina sub-phylum, and 80%

**78**

these areas.

**Table 1.**

*Impact of AMF bio-fertilizers to alleviate biotic and abiotic stress.*

of land plant species [8]. AMF are endophytic fungi with intra-radical hyphae that penetrate inside cortical cell and/or the root epidermis [7]. During this fungi and plant interaction, dialogues at molecular level take place, which result in host's metabolic modifications, protection against environmental stresses, and providing friendly conditions to symbiont (fungi) [2]. Arbuscules are formed by endomycorrhizal hyphae within the plant cortical cells and are highly branched, and mature arbuscules have short life and survive for 4–5 days. Arbuscules are considered as functional site for nutrient exchange [8]. These fungi benefit their hosts by increasing the uptake of nutrient elements (especially P) and enhancing the resistance to biotic or abiotic stresses [1, 7]. So far, a large number of publications demonstrated that AMF are an important regulator of the plants performance in different stressed environment (**Table 1**) such as heavy metal contained soils [20, 22], saline soils [13–15, 18, 20, 22, 23], soil subjected to drought stress [24]. AMF are also identified as regulator of biotic stress [21]. AMF association with plants not only improves plant growth but also improves soil texture by changing soil particles into stable aggregates that ultimately resists against wind and water erosion [15]. Mycorrhizal association is also helpful to introduce new plant species in new areas, occurring them ability to survive in a new environmental conditions [23]. Moreover, colonization of root by AMF can arise three sources of inoculum: spores, infected root and hyphae, collectively termed propagules [8].

As well as, with the emergence of sustainable development context the application of AMF bio-fertilizers starts to widen. It is assumed therefore, that the judicious use of these natural inoculants can reduce the need to amend soil with chemical fertilizers, thus increasing the viability of sustainable agriculture [15, 18]. **Figure 1** illustrates the role played by arbuscular mycorrhizal fungi in plant life cycle.

Thus selection of inoculum source constitutes an important parameter for the plantation successful. In fact, the response of AMF to abiotic stresses divers on the level of fungal species or ecotype; it was proven that indigenous strain occurs more beneficial effect into mitigates divers abiotic stress such as water deficiency, saline stress and heavy metals conditions by enhancing the active absorptive surface area which ultimately stimulates the uptake of water and nutrients [13–15, 20, 22, 23].

**81**

*Native Arbuscular Mycorrhizal Fungi and Agro-Industries in Arid Lands…*

**3. Production of arbuscular mycorrhizal fungi bio-fertilizers**

The commercial history of bio-fertilizers began with the launch of 'Nitragin' by Nobbe and Hiltner, a laboratory culture of Rhizobia in 1895, followed by the discovery of Azotobacter and then the blue green algae (BGA) and a host of other micro-organisms. Azospirillum and Arbuscular mycorrhizal fungi are fairly new discoveries [6]. Industrial manufacturing of AMF as crop inoculants is relatively new and, despite the practical demonstrations of their efficiency, their adoption by crop producers has been slow, most likely due to the quality and efficiency of marketed products [11]. In fact, production of previously selected AMF for their use as bio-fertilizers began in the decade of 1990 in a large part of the world [25]. Few companies throughout the world have manufactured and commercialized AMF inoculant using either a single AMF species or mixtures of AMF species that may include plant growth promoting rhizobacteria (PGPR) or other symbiotic and/or

The production of inoculum differs from fungi family to another. Arbuscular mycorrhizal fungi are strict obligatory symbionts, they dependent on the presence of a host plant to accomplish their development and their multiplication. The inoculum producer is then required to co-cultivate the "fungus-host plant" complex. Without the use of host plants it would be impossible to complete the mycorrhizal life cycle until the production of new propagules/spores [7]. In addition to this monosporic inoculant, it is possible to produce inoculant with different native species with greater ease and speed [7]. In comparison with the commercial inoculant, it has a low cost, higher taxonomic diversity, and the use of locally adapted species [25, 26], which increases the chances of positive effects on the plant and avoid the introduction of exotic species [27]. The use of AMF inoculant produced from the forest soil is the most reliable and recommended method because of its high species diversity, the potential to accelerate the ecological restoration of the soil environment and to promote the germination and growth of the plants [9, 25–27].

This method consists on AMF multiplication on pot culture with selective host

Native soil sampled from different plots of same natural sites must be mixed together to create one composite sample. The obtained mixture was distributed into pots (500 mL disposable cups) which were sown with trapping plant aiming to multiply and restore infective structures of the AMF species present in the trap cultures [27], and then kept in a greenhouse for four month. Two plant species are commonly used for trapping culture: cover "*Trifolum repens*" and leek "*Allium porrum*" [7, 27], But use of other legumes is also permitted such as Alfalfa "*Medicago sativa* [13] *Brachiaria* sp. [27]. Once the four month over, the areal part of plants is catted and the soils are mixed with roots for preparing a new plantation for other four months. Simultaneously, at each month, one pot of each plot was taken for analysis, using 50 g of soil for AMF spore isolation and identification and the roots for evaluation of the mycorrhizal colonization rate [26, 27]. A minimum of 12 months is required to obtain a good product, but the ideal is 24 months [13, 20]. Therefore, the obtained inoculums consist of different types of propagules: spores, fungal mycelium and fragments of mycorrhizal roots [7]. Multi-species products are closer

**3.1 Conventional method of AMF bio-fertilizers production**

*3.1.1 Mixture of AMF species bio-fertilizers production*

plant under controlled conditions in a greenhouse or in a grow room [7].

*DOI: http://dx.doi.org/10.5772/intechopen.94084*

biocontrol fungi [11].

**Figure 1.** *Role and importance of AMF symbiosis in plant life.*

*Native Arbuscular Mycorrhizal Fungi and Agro-Industries in Arid Lands… DOI: http://dx.doi.org/10.5772/intechopen.94084*

*Mycorrhizal Fungi - Utilization in Agriculture and Forestry*

collectively termed propagules [8].

plant life cycle.

[13–15, 20, 22, 23].

of land plant species [8]. AMF are endophytic fungi with intra-radical hyphae that penetrate inside cortical cell and/or the root epidermis [7]. During this fungi and plant interaction, dialogues at molecular level take place, which result in host's metabolic modifications, protection against environmental stresses, and providing friendly conditions to symbiont (fungi) [2]. Arbuscules are formed by endomycorrhizal hyphae within the plant cortical cells and are highly branched, and mature arbuscules have short life and survive for 4–5 days. Arbuscules are considered as functional site for nutrient exchange [8]. These fungi benefit their hosts by increasing the uptake of nutrient elements (especially P) and enhancing the resistance to biotic or abiotic stresses [1, 7]. So far, a large number of publications demonstrated that AMF are an important regulator of the plants performance in different stressed environment (**Table 1**) such as heavy metal contained soils [20, 22], saline soils [13–15, 18, 20, 22, 23], soil subjected to drought stress [24]. AMF are also identified as regulator of biotic stress [21]. AMF association with plants not only improves plant growth but also improves soil texture by changing soil particles into stable aggregates that ultimately resists against wind and water erosion [15]. Mycorrhizal association is also helpful to introduce new plant species in new areas, occurring them ability to survive in a new environmental conditions [23]. Moreover, colonization of root by AMF can arise three sources of inoculum: spores, infected root and hyphae,

As well as, with the emergence of sustainable development context the application of AMF bio-fertilizers starts to widen. It is assumed therefore, that the judicious use of these natural inoculants can reduce the need to amend soil with chemical fertilizers, thus increasing the viability of sustainable agriculture [15, 18]. **Figure 1** illustrates the role played by arbuscular mycorrhizal fungi in

Thus selection of inoculum source constitutes an important parameter for the plantation successful. In fact, the response of AMF to abiotic stresses divers on the level of fungal species or ecotype; it was proven that indigenous strain occurs more beneficial effect into mitigates divers abiotic stress such as water deficiency, saline stress and heavy metals conditions by enhancing the active absorptive surface area which ultimately stimulates the uptake of water and nutrients

**80**

**Figure 1.**

*Role and importance of AMF symbiosis in plant life.*
