Diversity of arbuscular mycorrhizal fungi in the rhizosphere of Plantago coronopus in Northwestern Algerian coast

Mycorrhizal fungi play a major role in the functioning of ecosystems. However, their identification has remained a challenge for scientific research. This study presents the first identification report of species of arbuscular mycorrhizal fungi in the rhizosphere of the halophyte Plantago coronopus L. in Algeria. Samples of rhizospheric soil were collected in spring 2018 at three sites in the Bomo-plage dunes west of Oran, Algeria. The spores were isolated by wet sieving, morphologically identified, and quantified. The mean spore density was 107.94 spores 100 g-1 dry soil, which is high compared to other dune ecosystems. Endomycorrhizal spore morphotypes were involved in the following Genus: Glomus, Septoglomus, Rhizophagus, Diversispora, Funneliformis, Dentiscutata, Claroideoglomus, Scutellospora, and Entrophospora, to the following Family: Glomeraceae, Gigasporaceae, Diversisporaceae, Claroideoglomeraceae, and Acaulosporaceae. The Glomeraceae was the most dominant identified family. The identification of indigenous arbuscular mycorrhizal fungi has been shown to be essential for future programs to restore disturbed dune ecosystems.

The use of soil biostructures created by soil fauna ecosystem engineers fed with different organic matterials as inoculum source of arbuscular mycorrhiza fungi on cocoa seedling

<p><span lang="IN">Soil fauna as ecosystem engineers </span><span>have the ability to </span><span lang="IN">creat</span><span>e </span><span lang="IN">soil biostructure</span><span>s, with the capacity to </span><span lang="IN">sav</span><span>e</span><span lang="IN"> arbuscular mycorrhizal fungi (AMF) spores. </span><span>This study therefore aims to </span><span lang="IN">investigate the </span><span>AMF </span><span lang="IN">spore density in the biostructures created by cooperation between earthworms and ants with a different organic matter composition</span><span>,</span><span lang="IN"> and to analyze the </span><span>biostructures’ </span><span lang="IN">potential as a source of </span><span>AMF </span><span lang="IN">inoculum on cocoa seedlings. </span><span>In the first experiment, a </span><span lang="IN">combination of earthworms and ants composition</span><span>, as well as a </span><span lang="IN">mixture of <em>G. sepium</em> leaf (GLP), cocoa shell bean (CSB), and sago dregs (SD)</span><span>,</span><span lang="IN"> was tested</span><span>. Meanwhile, </span><span lang="IN">in the </span><span>second</span><span lang="IN"> experiment</span><span>, t</span><span lang="IN">he</span><span> effect of</span><span lang="IN"> biostructures on cocoa seedlings grown </span><span>i</span><span lang="IN">n unsterile soil</span><span>,was </span><span lang="IN">examined</span><span>. According to the results, the highest</span><span lang="IN"> AMF spore </span><span>density was obtained using </span><span lang="IN">20 earthworms+10 ants with 50%GLP+50%CSB + 0%SD treatment</span><span>. Furthermore, the t</span><span lang="IN">otal AMF spores </span><span>were </span><span lang="IN">positively correlated</span><span> with the total P value, but negatively correlated </span><span lang="IN">with </span><span>the </span><span lang="IN">C/N ratio</span><span>. Therefore, bi</span><span lang="IN">ostructure application increased AMF spores number in rhizosphere and </span><span>the cocoa seedling’s </span><span lang="IN">root infection</span><span>. Furthermore, </span><span lang="IN">biostructure</span><span>s</span><span lang="IN"> resulting from the collaborative activity </span><span>between</span><span lang="IN"> different soil fauna ecosystem engineers </span><span>were able to transmit </span><span lang="IN">AMF spore</span><span>s </span><span lang="IN">to </span><span>infected </span><span lang="IN">plant root</span><span>s</span><span lang="IN"> growing </span><span>i</span><span lang="IN">n non-sterile soil.</span></p>

Alterations in Arbuscular Mycorrhizal Community Along a Chronosequence of Teak (Tectona grandis) Plantations in Tropical Forests of China

Arbuscular mycorrhizal (AM) fungi play a crucial role in promoting plant growth, enhancing plant stress resistance, and sustaining a healthy ecosystem. However, little is known about the mycorrhizal status of teak plantations. Here, we evaluated how the AM fungal communities of rhizosphere soils and roots respond to different stand ages of teak: 22, 35, 45, and 55-year-old from the adjacent native grassland (CK). A high-throughput sequencing method was used to compare the differences in soil and root AM fungal community structures. In combination with soil parameters, mechanisms driving the AM fungal community were revealed by redundancy analysis and the Mantel test. Additionally, spore density and colonization rates were analyzed. With increasing stand age, the AM fungal colonization rates and spore density increased linearly. Catalase activity and ammonium nitrogen content also increased, and soil organic carbon, total phosphorous, acid phosphatase activity, available potassium, and available phosphorus first increased and then decreased. Stand age significantly changed the structure of the AM fungal community but had no significant impact on the diversity of the AM fungal community. However, the diversity of the AM fungal community in soils was statistically higher than that in the roots. In total, nine and seven AM fungal genera were detected in the soil and root samples, respectively. The majority of sequences in soils and roots belonged to Glomus. Age-induced changes in soil properties could largely explain the alterations in the structure of the AM fungal community along a chronosequence, which included total potassium, carbon-nitrogen ratio, ammonium nitrogen, catalase, and acid phosphatase levels in soils and catalase, acid phosphatase, pH, and total potassium levels in roots. Soil nutrient availability and enzyme activity were the main driving factors regulating the shift in the AM fungal community structure along a chronosequence of the teak plantations.

Perbanyakan Agen Hayati Trichoderma Sp. Menggunakan Media Beras di Laboratorium Pengamatan Hama dan Penyakit Tanaman Banyumas

The rhizosphere area of a plant is an area rich in microbes, one of which is a group of fungi. This practical work aims to multiply Trichoderma sp. in the rhizosphere of bamboo plants in the Jatilawang area using rice as a medium. This practical work uses rice and coconut media in conducting exploration. The results of practical work obtained spore density of Trichoderma sp. meet the standards for application in plants. Obstacles in exploring Trichoderma sp. is takes a long time.

Effectiveness Test of Trichoderma harzianum on The Development of Anthracnose Disease (Colletotrichum musae) of Ambon Banana

The decrease in the quality of bananas can be caused by the attack of the pathogen Colletotrichum musae which causes anthracnose disease. The use of the antagonist fungus Trichoderma harzianum can be relied upon to control this disease. This study aimed to obtain a more effective level of T. harzianum spore density to suppress the development of anthracnose disease in Ambon bananas. The treatment tested was T. harzianum with five levels of spore density, namely 105, 106, 107,108, and 109 spore/mL, designed using a completely randomized design with five replications. The variables observed were the incubation period and the intensity of the disease. The results showed that the spore density of 109 was effective in suppressing the development of anthracnose disease by inhibiting the incubation period to 3.85 days and suppressing the intensity of the disease to 41.4%.Keywords: Banana, Trichoderma harzianum, Anthracnose, Colletotrichum musae

An In Vitro Study of The Spore Densities Effect of Trichoderma spp. as Biocontrol Agent for Fusarium Wilt in Cayenne Pepper (Capsicum sp.)

Root disease controlling has been a challenge in increasing plant productivity. The soil-borne pathogens become the main concern which mostly infects the root surface. One of the most common soil-borne pathogens is Fusarium oxysporum (Fo). Cayenne pepper (Capsicum sp.) is one of the most abundant commodities and contributes significantly to the economy. This plant is also susceptible to Fusarium wilt infection. The use of endophytic fungi as biocontrol agents is an alternative against soil-borne pathogens, one of which is Trichoderma spp. fungi. This study aims to determine the effectiveness of various spore densities of Trichoderma spp. against the pathogen Fo. The research was conducted through an in vitro study by antagonistic testing between spore suspensions of Trichoderma spp. (103, 105, and 107 spores/mL) with Fo. The results showed the density of 107 spores/mL gave the highest percentage of inhibition (54.59%) compared to spore density of 103 (35.27%) and 105 spores/mL (44.44%). The spore density of 107 spores/mL gave a significant difference in response to the density of other spores according to the BNT test at a significance level of 5% and was able to inhibit the growth of Fo more than 50%. The results of this study are expected to be a reference for the formulation of Trichoderma spp. which is ideal for controlling Fo pathogens in the fields.

Mycorrhizal fungi Glomus spp. propagation in zeolite enriched with mycorrhiza helper bacteria for controlling nematode in coffee

Arbuscular mycorrhizal fungi (AMF) play a role in suppressing the nematode Pratylenchus coffeae. Mycorrhizal helper bacteria (MHB) can increase the effectiveness of AMF to control the diseases. The experimental purpose was to increase the spore population of AMF Glomus spp. in zeolite-based formulation inoculated with liquid consortia of Pseudomonas diminuta and Bacillus subtilis as MHB. The experimental design was a completely random design with six treatments consisted of 106, 107, 108, and 109 CFU/mL MHB liquid inoculants. The control treatments were water and 2% molasses. All treatments were replicated four times. A total of 300 mL/pot Liquid inoculant of MHB have been inoculated a three day before transplanting the maize seedling to the Zeolite inoculated with Glomus spp. in the pot. One month after MHB inoculation, Glomus formulation in Zeolite with different levels of MHB increased the degree of infection. Three months after MHB inoculation, spore content in Zeolite increased. The density of P. diminuta and B. subtilis in zeolite-based mycorrhizal inoculant increased at the end of the experiment. Liquid inoculant MHB contained 108 CFU/mL enhanced spora number fourth times compared to the control. This experiment suggests that P. diminuta and B. subtilis were effective to increase the spore density of AMF inoculant.

Harnessing Acremonium zonatum (Sawada) Gams oil formulations as water hyacinth control mycoherbicides.

The effect of formulating Acremonium zonatum (Saw.) Gams in corn oil, mineral oil and glycerol was determined in a glasshouse at Maseno University Botanic Garden and laboratory. The study was situated at latitude -100’ 00’’ S and longitude 340 36’ 00’’E. A. zonatum was aseptically isolated from symptomatic plants and inoculated upon healthy water hyacinth plants in a CRD experiment. Data was analyzed using SPSS version 20 computer software. Oil and spore density effects were statistically significant at p < 0.05. The main effect of oil yielded an effect size of 0.281 indicating that 28.1 % of the variance in disease severity was explained by the oil formulation (F(2, 28) = 5.459, p = 0.01). Spore density yielded an effect size of 0.326 indicating that 32.6% of the variance in the study was explained by spore density (F(3, 28) = 4.515, p = 0.011). The interaction effect was not significant (F(6, 28) = 0.199, p = 0.974) indicating that there was no combined effect for the kind of oil used in the formulation of the A. zonatum and the spore density. The results suggested that A. zonatum pathogenicity varies with different spore concentrations, 1x 108 spores/ml being the most potent. A. zonatum has favorable characteristics for consideration as a mycoherbicide. Corn oil as formulation material was concluded to be the best formulation material for A. zonatum.

Application of wheat flour (Triticum aestivum) on spore density and sporulation efficiency of Bacillus megaterium isolated from Litopenaeus vannamei gastrointestinal tract

Mahariawan IMD, Kusuma WE, Yuniarti A, Beltran MAG, Hariati AM. 2021. Application of wheat flour (Triticum aestivum) on spore density and sporulation efficiency of Bacillus megaterium isolated from Litopenaeus vannamei gastrointestinal tract. Biodiversitas 22: 3709-3715. Bacillus megaterium is frequently used in fish farming, such as white shrimp (Litopenaeus vannamei) pond, which can produce spores with high stability in its implementation. Currently, spore production still requires the availability of high-cost carbon sources. The objective of this research was to evaluate the effect of different wheat flour doses on spore density and sporulation efficiency of B. megaterium BM1. In flasks, 50 mL of each test medium was treated with different doses of wheat (10, 20, 30 and 40 g. L-1, respectively) and glucose was used as a control. Each treatment was inoculated with B. megaterium BM1 (2.6 x 108 CFU. mL-1) and incubated in a shaker incubator (120 rpm) at 37 °C for 120 hours. The results showed that the highest vegetative cell concentration (17 x 108 CFU. mL-1), growth rate (0.8 hour-1) and spore (14.7 x 108 spores. mL-1) were found in the wheat flour dose of 30 g. L-1. Furthermore, the highest sporulation efficiency was achieved at 20 g. L-1 of wheat (91.30%) and germination should be done at a dose less than 40 g. L-1. The size of the spores was 1.35-1.39 µm. Thus, 30 g. L-1 of wheat flour is a potential dose to produce spore for probiotic candidates.

Formalin-casein enhances water absorbency of calcium alginate beads and activity of encapsulated Metarhizium brunneum and Saccharomyces cerevisiae

The control of root-feeding wireworms has become more challenging as synthetic soil insecticides have been progressively phased out due to environmental risk concerns. Innovative microbial control alternatives such as the so-called attract-and-kill strategy depend on the rapid and successful development of dried encapsulated microorganisms, which is initiated by rehydration. Casein is a functional additive that is already used in food or pharmaceutical industry due to its water binding capacity. Cross-linked forms such as formalin-casein (FC), exhibit altered network structures. To determine whether FC influences the rehydration of alginate beads in order to increase the efficacy of an attract-and-kill formulation for wireworm pest control, we incorporated either casein or FC in different alginate/starch formulations. We investigated the porous properties of alginate/starch beads and subsequently evaluated the activities of the encapsulated entomopathogenic fungus Metarhizium brunneum and the CO2 producing yeast Saccharomyces cerevisiae. Adding caseins altered the porous structure of beads. FC decreased the bead density from (1.0197 ± 0.0008) g/mL to (1.0144 ± 0.0008) g/mL and the pore diameter by 31%. In contrast to casein, FC enhanced the water absorbency of alginate/starch beads by 40%. Furthermore, incorporating FC quadrupled the spore density on beads containing M. brunneum and S. cerevisiae, and simultaneous venting increased the spore density even by a factor of 18. Moreover, FC increased the total CO2 produced by M. brunneum and S. cerevisiae by 29%. Thus, our findings suggest that rehydration is enhanced by larger capillaries, resulting in an increased water absorption capacity. Our data further suggest that gas exchange is improved by FC. Therefore, our results indicate that FC enhances the fungal activity of both fungi M. brunneum and S. cerevisiae, presumably leading to an enhanced attract-and-kill efficacy for pest control. Graphic abstract