Exploration of mahogany and cocoa rhizosphere fungi as agroforestry land cover in Herlang District, Bulukumba Regency

Herlang District has an agricultural cultivation area of 6,160.10 Ha and consists of various land management systems, such as paddy fields, not paddy fields (corn and green beans), plantation potential (cashew, mahogany, and cocoa), as well as in Herlang District has various agroforestry land management. Agroforestry is an effort to increase biodiversity without the exception of soil microbes such as fungi which stimulate soil biological activity. This study aims to identify rhizosphere fungi from two different plant vegetation as agroforestry land cover. The research method used was the isolation of the fungus using a 10−2 dilution technique, as well as the identification of the fungus based on its macroscopic and microscopic forms. Exploration results of mahogany and cocoa rhizosphere fungi as agroforestry land cover in Herlang District, Bulukumba Regency, obtained 3 4 isolates consisting of 5 genera, namely, Aspergillus sp., Fusarium sp., Penicillium sp., Rhizopus sp., and Trichoderma sp.


Introduction
Herlang District has cultivated agricultural land of 6,160.10Ha and consists of various land management systems, such as paddy fields, non-rice fields (corn and green beans), plantation potential (cashew, mahogany, and cocoa) [1], as well as Herlang District there are various agroforestry land management methods, such as in Karassing Village and Tanuntung Village.In Karassing Village, the agroforestry system is covered with vegetation of mahogany, cocoa, banana, and white teak (dominantly covered with mahogany vegetation).Whereas in Tanuntung Village the agroforestry system is covered with vegetation of mahogany, cocoa, banana, cashew, and elephant grass to the point that there are even livestock activities in it (dominantly covered with vegetation of mahogany and cocoa).
In general, an agroforestry system is a system in which there are three components, including forestry, agriculture, and animal husbandry components.The forestry and agricultural component in question is the growth of trees that have deep roots and are able to spread to the subsoil so that there is a reduction in nutrient leaching both vertically and horizontally and the vegetation found in agroforestry systems can act as a ground cover and as an effort to increase biodiversity.without exception soil microbes such as fungi which stimulate soil biological activity [2].
Soil biological activity is basically played by microorganisms (soil microbes) such as fungi that interact with the soil to the rhizosphere of plants [3].Agroforestry systems can support and trigger the growth of soil microorganisms, which are generally found in the rhizosphere where soil microorganisms are abundant in the soil.The existence of soil microorganisms is influenced by the availability of food or energy sources for soil microbes, the appropriate temperature, and the availability of sufficient water in the rhizosphere [4].
The rhizosphere is perfectly inhabited by fungi, because fungi have special properties, namely being able to grow quickly and being able to utilize simple carbon compounds [5].Plant roots in their growth are able to secrete compounds that dissolve easily in water in the form of amino acids, sugars, and organic acids which can provide food for microbes so the availability of food for microbes will have an impact on high microbial activity and be able to provide nutrients for plants [3] .The diversity of soil microorganisms encountered is influenced by interactions between plants, soil fertility, physical environmental conditions, and pressure from other microorganisms [6].The rhizosphere of mahogany and cocoa vegetation which forms agroforestry land cover may have different organic acids, amino acids and sugars, which can affect the number and types of fungi associated with the mahogany and cocoa rhizosphere.
The existence of various species of fungi in the soil rhizosphere is influenced by several factors such as the availability of nutrients to help the fungus reproduce, therefore it is necessary to conduct research to obtain information regarding the presence of rhizosphere fungi in mahogany and cocoa vegetation cultivated as agroforestry land cover, in two locations of agroforestry systems.different.

Soil sampling
Soil samples for the study were taken from the rhizosphere area of mahogany and cocoa vegetation using purposive sampling on two different agroforestry lands, namely in Karassing Village and Tanuntung Village, which are included in the Herlang District, Bulukumba Regency.Rhizosphere soil is taken as much as 250 g with a depth of 20-30 cm from the soil surface and coordinates are taken using GPS.Then 4 sampling points were obtained for each plant which was then composited and the soil samples were put in containers and labeled.

Rhizosphere fungi isolation
Isolation of rhizosphere fungi began with a multilevel dilution technique, then the rhizosphere soil samples of each plant that had been composited were weighed as much as 1 g which would then be suspended in 9 ml of sterile distilled water and then homogenized using a vortex to obtain a dilution level of 10 -1 .The procedure was repeated until a 10 -2 dilution level was obtained.Then the results of the 10 -2 dilution were taken at 0.5 ml to be poured into a petri dish containing sterile Potato Dextrose Agar media using a micropipette.Then the suspension was incubated at room temperature 27-28°C for 5-7 days [7].

Purification of rhizosphere fungi
Purification was carried out by re-isolating single colonies that grew on the isolated results from rhizosphere soil samples, then every single colony was re-grown on new PDA media and incubated for approximately 3-5 days [8].

Identification of Rhizosphere Fungi
Identification of rhizosphere fungi begins by taking fungal colonies using a needle, then placing them on a glass object and adding one drop of distilled water using a dropper, then covering them using a cover glass and then observing conidia and conidiophores using a microscope and identification of fungi is carried out based on the guidebook Illustrated Genera of Imperfect Fungi [9].

Identification of mahogany and cocoa rhizosphere fungi as agroforestry land cover in Karassing Village
The results of isolation of the mahogany rhizosphere fungus as agroforestry land cover in Karassing Village obtained 11 isolate cultures, of which there were 2 isolates from the genus Aspergillus sp., 3 isolates from the genus Fusarium sp., 2 isolates from the genus Penicillium sp., 1 isolate from the genus Rhizopus sp. and 3 isolates from the genus Trichoderma sp.The results of macroscopic and microscopic observations can be seen in Table 1.  1 shows the results of macroscopic and microscopic observations of fungi isolated from the mahogany rhizosphere as agroforestry land cover in Karassing Village.The genus Aspergillus sp.macroscopically shows that the fungus colonies are black with a sandy texture and microscopically it shows round, lumpy conidia and conidiophores that are long and erect.The genus Fusarium sp.macroscopically shows the form of colony growth and the color of the colonies which grow evenly and are white in color and have oval-shaped conidia.The genus Penicillium sp.macroscopically shows that the colony is dark green in color and microscopically has conidia arranged in chains and branched conidiophores.The genus Rhizopus sp.Macroscopically it shows that the colony is white and microscopically has a single conidium up to 2-3 conidia.The genus Trichoderma sp.macroscopically has white rather greenish colonies and microscopically it has round conidia and conidiophores which are arranged and branched.
Meanwhile, in the cocoa rhizosphere, 6 isolates were obtained, including 5 fungi isolates from the genus Fusarium sp. and 1 isolate from the genus Penicillium sp.The results of macroscopic and microscopic observations can be seen in Table 2.  2 shows the results of macroscopic and microscopic observations of fungi isolated from the cocoa rhizosphere as agroforestry land cover in Karassing Village.The genus Fusarium sp. has colonies that are slightly yellowish-white in color and microscopically have oval-shaped conidia.While genus Penicillium sp.macroscopically has white colonies with a velvety texture and microscopically it has conidia that are intertwined like chains.

Identification of mahogany and cocoa rhizosphere fungi as agroforestry land cover in Tanuntung Village
The results of isolation of the mahogany rhizosphere fungus as agroforestry land cover in Tanuntung Village obtained 11 isolate cultures, of which there were 2 fungi isolates from the genus Aspergillus sp., 6 isolates from the genus Fusarium sp., 2 isolates from the genus Penicillium sp., and 1 isolate from the genus Rhizopus sp.The results of macroscopic and microscopic observations can be seen in Table 3.   3 shows the results of macroscopic and microscopic observations of fungi isolated from the mahogany rhizosphere as agroforestry land cover in Tanuntung Village.The genus Aspergillus sp.Macroscopically it shows that isolates have yellowish-black colonies and microscopically they have round, lumpy conidia and conidiophores that are long and upright.The genus Fusarium sp.macroscopically has colony growth or colony color which is slightly yellowish white and microscopically has oval-shaped conidia.The genus Penicillium sp.Macroscopically it shows that the colonies of the genus Penicillium are slightly pinkish white in color and microscopically have conidia that are neatly arranged in clumps resembling chains.The genus Rhizopus sp.macroscopically shows that the colony is white and microscopically has a single conidium and there may also be 2 to 3 conidia.
Meanwhile, in the cocoa rhizosphere, 6 isolates were obtained, including 1 fungus isolate from the genus Aspergillus sp. and 5 isolates from the genus Fusarium sp.The results of macroscopic and microscopic observations can be seen in Table 4. Table 4 shows the results of macroscopic and microscopic observations of fungi isolated from the cocoa rhizosphere as agroforestry land cover in Tanuntung Village.The genus Aspergillus sp.macroscopically showed that the isolate had black colonies with a sand texture and microscopically had conidia that were round and clumped.The genus Fusarium sp.macroscopically shows the form of colony growth and the color of the colony which is slightly yellowish-white, cottony textured, and microscopically the isolates have oval-shaped conidia.
Based on the exploration results of mahogany and cocoa rhizosphere fungi as agroforestry land cover in Herlang District, Bulukumba Regency, 3 4 isolates were obtained consisting of 5 genera, namely, Aspergillus sp., Fusarium sp., Penicillium sp., Rhizopus sp., and Trichoderma sp. .This shows that the agroforestry land management system has quite diverse rhizosphere fungi.Agroforestry systems have been considered a form of sustainable land use.Woody species in agroforestry systems can improve the physicochemical properties of soil by supplying leaf or stem litter so that an increase in the abundance of certain rhizosphere fungal populations is detected in agroforestry systems [10].
With a total of 34 isolates, 17 isolates came from agroforestry land cover in Karassing Village (11 isolates from the mahogany rhizosphere and 6 isolates from the cocoa rhizosphere), while 17 isolates came from agroforestry land cover in Tanuntung Village (11 isolates from mahogany rhizosphere).and 6 isolates from the cocoa rhizosphere).This shows that the number of isolates obtained from mahogany and cocoa rhizosphere was 11 isolates (mahogany rhizosphere) and 6 isolates (cocoa rhizosphere) respectively in two agroforestry land management systems or different locations.This is in accordance with previous research that exploration of rhizosphere fungi on Mahogany stands in Takalar District obtained 17 belonging to 5 types of rhizosphere fungi, namely Rhizopus, Fusarium, Aspergillus, Penicillium and Gliocladium and in Maros District obtained 11 belonging to 4 genera, Trichoderma, Gliocladium, Rhizopus and Aspergillus [11].
Of the 34 fungal isolates that have been explored at two locations of agroforestry land management systems, it shows that the genus Fusarium sp. is the most dominant among other genera of fungi.In addition, when viewed based on the type of vegetation, the number of isolates from the genus Fusarium in the cocoa rhizosphere (10 isolates) was more than in the mahogany rhizosphere (9 isolates), but overall the most dominant isolates came from the genus Fusarium sp.Fusarium is a fungus that is known to be able to colonize plant root areas well [12].Some fungi are that are pathogenic (causing plants to wilt) and entomopathogenic (infecting insects that are detrimental to plants) [13].
The most dominant isolate came from the genus Fusarium sp.(19 isolates), followed by the genus Aspergillus sp. and Penicillium sp.(5 isolates each), the genus Trichoderma sp.(3 isolates), and the genus Rhizopus sp.(2 isolates).As well as the exploration results showed that the genera Aspergillus sp., Fusarium sp., and Penicillium sp. can be found in the rhizosphere of mahogany and cocoa but not (ii) (i) in the genus Trichoderma sp. and Rhizopus sp. which can only be found in the mahogany rhizosphere.This can be caused by the unavailability of energy sources needed by fungi in the rhizosphere of plants.Differences in the diversity of fungi are influenced by the availability of nutrients, as well as the availability of organic matter and roots in the soil is also very influential [14].

Conclusion
Five genera of mahogany rhizosphere fungi were obtained as agroforestry land cover in Herlang District, namely Aspergillus sp.Fusarium sp., Penicillium sp., Rhizopus sp., and Trichoderma sp.Meanwhile, only 3 genera of fungi were found in the cocoa rhizosphere, namely Aspergillus sp.Fusarium sp., and Penicillium sp.

Figure 1 .
Figure 1.Location of rhizosphere soil sampling points in Karassing Village.

Figure 2 .
Figure 2. Location of rhizosphere soil sampling points in Tanuntung Village.

Table 4 .
Macroscopic and microscopic observation of cocoa rhizosphere fungi in Tanuntung Village.

Table 1 .
Macroscopic and microscopic observations of mahogany rhizosphere fungi in Karassing Village.

Table 2 .
Macroscopic and microscopic observations of cocoa rhizosphere fungi in Karassing Village.