First Report of Crown and Root Rot in Strawberry Caused by Macrophomina phaseolina in Israel

A phenomenon of wilting in strawberry (Fragaria × ananassa Duchesne) transplants, cultivated for annual winter production, was observed on several cultivars at 14 farmers' plots in nine growing regions in Israel during September and October 2004. Typical ‘charcoal rot’ symptoms included necrotic root and crown rot accompanied by plant wilting and chlorosis of leaves (1). Pure cultures of Macrophomina phaseolina were isolated from affected roots and crowns of plants (1) when incubated at 25°C in the dark on potato dextrose agar (PDA) (Difco Laboratories, Sparks, MD) medium containing 250 mg/l of chloramphenicol. Dark, oblong sclerotia averaging 40 μm wide by 200 μm long were observed in the infected root tissue and in culture 7 to 10 days after isolation (2). Twenty-two single sclerotium isolates were recovered from five infected cultivars (Yuval, Herut, Tamar, Hadas, and Malach) and three representative isolates were used in two pathogenicity assays. Inoculum of M. phaseolina was produced by blending 3-week-old cultures on PDA plates (9 cm diameter) in 100 ml of sterile distilled water, filtering the suspension through eight layers of gauze, and adjusting the concentration to 105 sclerotia per ml. In the first pathogenicity assay, each of the three isolates was inoculated on five plants (cv. Malach). Plants were produced from nursery runners and potted in a soilless coconut and styrofoam (3:1 vol/vol) medium, 1 liter per pot. Each plant was inoculated by pouring 50 ml of sterile water containing 105 sclerotia per ml per pot. Plants were incubated at 30°C with 12-h day/night conditions and watered with 100 ml every 3 to 7 days. Five noninoculated control plants were included. Necrosis at the base of petioles and chlorosis of leaves, followed by initial wilting of leaves, were observed after 2 weeks on inoculated plants. Plant mortality was first recorded approximately 5 weeks after inoculation and 100% mortality was recorded 10 weeks postinoculation. In the second pathogenicity assay, the same three isolates were used to inoculate four plants each of two different cultivars (Malach and Hadas) as described previously. Identical disease symptoms, as described previously, were observed 17 days after inoculation. Initial plant mortality was observed approximately 6 weeks postinoculation. In both pathogenicity assays, M. phaseolina was readily reisolated on amended PDA from all symptomatic and dead plants, which successfully completed Koch's postulates. Noninoculated control plants remained healthy. Although M. phaseolina has been reported in other crops in Israel, to our knowledge, this is the first report of the pathogen on strawberry in our country. This study suggests that the current soil fumigation regimen for control of fungal pathogens such as M. phaseolina, utilizing alternatives to methyl bromide which is currently being phased out in Israel, may not be adequate to maintain healthy strawberry material at all production stages. A similar observation was recently reported in Florida (2). Charcoal rot of strawberry has also been recorded on strawberry in France, India, and Egypt (1). References: (1) J. Maas. Macrophomina leaf blight and dry crown rot and Macro-phomina root rot and charcoal rot. Pages 26 and 59 in: Compendium of Strawberry Diseases. 2nd ed. J. L. Maas, ed. The American Phytopathological Society, St. Paul, MN, 1998. (2) J. Mertely et al. Plant Dis. 89:434, 2005.

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First Report of Macrophomina phaseolina Causing a Crown Rot of Strawberry in Florida

Plant Disease ◽

10.1094/pd-89-0434a ◽

2005 ◽

Vol 89 (4) ◽

pp. 434-434 ◽

Cited By ~ 29

Author(s):

J. Mertely ◽

T. Seijo ◽

N. Peres

Keyword(s):

Methyl Bromide ◽

Block Design ◽

Vascular Ring ◽

Macrophomina Phaseolina ◽

Crown Rot ◽

American Phytopathological Society ◽

Charcoal Rot ◽

Isolation Medium ◽

Potato Dextrose Broth ◽

First Report

Strawberry (Fragaria × ananassa Duchesne) is produced as an annual winter crop in raised, plastic-mulched beds on 2,800 ha in west central Florida. In December 2001, a grower submitted collapsed and dying strawberry plants from a commercial field to the University of Florida in Dover. The cut crowns of affected plants revealed dark brown necrotic areas on the margins and along the woody vascular ring. Macrophomina phaseolina was isolated from pieces of infected tissue cut aseptically from the crowns and placed on a medium containing 12 g of Difco potato dextrose broth, 17 g of Bacto agar, 250 mg of ampicillin, and 100 mg of streptomycin sulfate per liter of water. The fungus produced numerous, dark, oblong sclerotia in the isolation medium after 4 to 5 days incubation at 24°C under constant fluorescent lighting. In 10-day-old cultures, sclerotia ranged in size from 55 to 190 μm long by 50 to 135 μm wide (average 105 × 74 μm). Ostiolate pycnidia bearing relatively large, broadly ellipsoidal, hyaline conidia occasionally developed on the host tissue after 8 to 10 days of incubation (2). During the 2003-2004 season, M. phaseolina was isolated from dying strawberry plants taken from the original field and two additional farms. Affected plants were often found along field margins or other areas inadequately fumigated with methyl bromide. Two single-spore isolates from different fields were tested for pathogenicity on nursery runner plants (cv. Strawberry Festival) grown for 4 weeks in the greenhouse on artificial potting soil. The fungal isolates were grown on corn meal agar at 24°C for 4 days and allowed to colonize sterile wooden toothpicks placed on the medium for an additional 5 days. Prior to use, the toothpicks were sterilized by autoclaving twice in deionized water and a third time in V8 juice. Six plants were inoculated with each isolate by inserting a colonized toothpick into each crown. Sterile, V8-infused toothpicks were inserted into the crowns of corresponding control plants. The plants were incubated in a greenhouse in a randomized complete block design with two replicates of three plants each. After 3 days, 33 to 100% of the inoculated plants developed wilting in one or more leaves. All inoculated plants collapsed or died within 2 weeks of inoculation, while the control plants remained healthy during the observation period. The pathogen was readily reisolated from inoculated plants. Charcoal rot disease caused by M. phaseolina has been reported on strawberry in France, India, and Illinois (2,3). To our knowledge, this is the first report from Florida. M. phaseolina may be an emerging threat as the Florida strawberry industry transitions from methyl bromide to other fumigants in 2005. References: (1) J. Maas. Macrophomina leaf blight and dry crown rot. Page 26 in: Compendium of Strawberry Diseases. 2nd ed. J. L. Maas, ed. The American Phytopathological Society, St. Paul, MN, 1998. (2) G. S. Smith and T. D. Wyllie. Charcoal rot. Pages 29–31 in: Compendium of Soybean Diseases. G. L. Hartman et al., eds. 4th ed. The American Phytopathological Society, St. Paul, MN. 1999. (3) B. Tweedy et al. Plant Dis. Rep. 42:107, 1958.

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First Report of Charcoal Rot of Sugar Beet Caused by Macrophomina phaseolina in Greece

Plant Disease ◽

10.1094/pdis.2002.86.9.1051d ◽

2002 ◽

Vol 86 (9) ◽

pp. 1051-1051 ◽

Cited By ~ 2

Author(s):

D. A. Karadimos ◽

G. S. Karaoglanidis ◽

K. Klonari

Keyword(s):

Sugar Beet ◽

Root Rot ◽

Pathogenic Fungi ◽

Macrophomina Phaseolina ◽

Northern Greece ◽

Charcoal Rot ◽

First Report ◽

Yellow Mustard ◽

External Part ◽

Sugar Beet Crop

During the summer of 2000 in the Amyndeon area of northern Greece, sugar beet (Beta vulgaris L.) roots with rot symptoms were observed in many fields. Initially, the plants wilted, and leaves soon turned brown and died. Diseased plants appeared in patches in the field. Brown-black lesions were observed in the external part of the root crown while yellow-mustard colored lesions occurred internally. In advanced stages of decay, masses of sclerotia formed in rotted cavities and roots became mummified. Macrophomina phaseolina (Tassi) Goid. (1) was isolated on potato dextrose agar (PDA) from 30 rotted roots collected in five fields. Cultures produced dark multi-septate mycelium and sclerotia, which were black, smooth, spherical to irregular in shape, and varied in size from 100 μm to 1mm in diameter. Five isolates were evaluated for pathogenicity on surface-sterilized 16-week-old sugar beet roots (cv. Rizor) by placing a 5-mm-diameter PDA plug of actively growing mycelium in wounds made with a sterile knife. Sterile PDA plugs were placed in wounds made in control beet roots. Ten roots were inoculated per isolate. Roots were kept at 25°C in the dark for 10 days. Extensive decay of inoculated roots developed, similar to decay observed in the field, and M. phaseolina was reisolated from rotted tissue. Control roots showed no decay. This pathogen has been previously reported as a root rot pathogen of sugar beet in California, India, and countries of the former USSR. Charcoal rot is of minor economic importance since M. phaseolina attacks mainly weakened plants under conditions of high temperature (2). To our knowledge, this is the first report of charcoal root rot of sugar beet in Greece. References: (1) Anonymous. Macrophomina phaseolina. No. 275 in: Descriptions of Plant Pathogenic Fungi and Bacteria. CMI, Kew, Surrey, UK, 1970. (2) J. E. Duffus and E. G. Ruppel. Diseases. Page 347 in: The Sugar Beet Crop. Science into Practice. D. A. Cooke and R. K. Scott eds. Chapman and Hall, NY, 1993.

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First Report of Crown Rot of Strawberry Caused by Macrophomina phaseolina in Chile

Plant Disease ◽

10.1094/pdis-12-12-1121-pdn ◽

2013 ◽

Vol 97 (7) ◽

pp. 996-996 ◽

Cited By ~ 14

Author(s):

S. Sánchez ◽

M. Gambardella ◽

J. L. Henríquez ◽

I. Díaz

Keyword(s):

Cross Sections ◽

Vascular Ring ◽

Aerial Mycelium ◽

Macrophomina Phaseolina ◽

The United States ◽

Causal Agent ◽

Crown Rot ◽

First Report ◽

San Pedro ◽

Pure Cultures

In recent years, an increase of collapsed and dead strawberry plants has been observed in several fields in central Chile, specifically in San Pedro, Melipilla, an important area for strawberry cultivation in the country. To determine the causal agent of the disease and the extent of the problem, 25 sample sites of 1 ha each, distributed in different San Pedro zones, were surveyed at the end of the 2011 season (from December 2010 to February 2011). Cross sections of the crowns of symptomatic strawberry plants showed necrotic tissue and brown-red to dark brown areas on the vascular ring. Samples of the affected crowns were superficially disinfested and plated on potato dextrose agar with 200 μg/ml of streptomycin sulfate. Dark gray colonies were observed after 7 days of incubation at 24°C. Pure cultures of the pathogen showed aerial mycelium and abundant dark oblong sclerotia. Fifty sclerotia were measured, averaging 120 × 74 μm. Twenty-one isolates were identified molecularly utilizing the species specific primers MpKFI and MpKRI (2) that yielded a 350-bp fragment. The amplified DNA fragments were sequenced and BLAST analysis showed a 99% nucleotide sequence identity with Macrophomina phaseolina (GeneBank Accession No JX535007.1). Both morphological and molecular analyses confirmed that the isolated species corresponded to M. phaseolina, causal agent of crown and root rot in strawberry. Four representative isolates were selected to conduct pathogenicity tests. Inoculum was prepared by incubating the pathogen for 28 days at 20°C in sterilized oat seeds. Pots of 1.5 liters were filled with a mixed substrate of peat and perlite (2:1), amended with inoculated oats at 9 g per liter of substrate. ‘Camarosa’ strawberry plants were planted and grown in a glasshouse for 1 month. Six replicated plants per isolate and six plants growing on non-inoculated substrate were left as controls. Ninety-five percent of the inoculated plants showed wilt and collapse symptoms 22 days after transplant, whereas no symptoms were observed in the control plants. M. phaseolina was reisolated from the crowns of symptomatic plants, fulfilling Koch's postulates. The pathogen was isolated from symptomatic strawberry plants in 14 of the 25 sampled sites. Although M. phaseolina was described previously on other crops in Chile, to our knowledge, this is the first report of M. phaseolina causing crown rot of strawberry. The disease has been recently reported in Spain, the United States, and Argentina (1,3,4). References: (1) M. Avilés et al. Plant Pathol. 57:382, 2008. (2) B. Babu et al. Mycologia 99:797, 2007. (3) O. Baino et al. Plant Dis. 95:1477, 2011. (4) S. Koike. Plant Dis. 92:1253, 2008.

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Biological control of strawberry crown rot, root rot and grey mould by the beneficial fungus Aureobasidium pullulans

BioControl ◽

10.1007/s10526-021-10083-w ◽

2021 ◽

Author(s):

Mudassir Iqbal ◽

Maha Jamshaid ◽

Muhammad Awais Zahid ◽

Erik Andreasson ◽

Ramesh R. Vetukuri ◽

...

Keyword(s):

Root Rot ◽

Fungal Pathogens ◽

Aureobasidium Pullulans ◽

Grey Mould ◽

Lesion Size ◽

Plant Diseases ◽

Crown Rot ◽

Whole Plants

AbstractUtilization of biocontrol agents is a sustainable approach to reduce plant diseases caused by fungal pathogens. In the present study, we tested the effect of the candidate biocontrol fungus Aureobasidium pullulans (De Bary) G. Armaud on strawberry under in vitro and in vivo conditions to control crown rot, root rot and grey mould caused by Phytophthora cactorum (Lebert and Cohn) and Botrytis cinerea Pers, respectively. A dual plate confrontation assay showed that mycelial growth of P. cactorum and B. cinerea was reduced by 33–48% when challenged by A. pullulans as compared with control treatments. Likewise, detached leaf and fruit assays showed that A. pullulans significantly reduced necrotic lesion size on leaves and disease severity on fruits caused by P. cactorum and B. cinerea. In addition, greenhouse experiments with whole plants revealed enhanced biocontrol efficacy against root rot and grey mould when treated with A. pullulans either in combination with the pathogen or pre-treated with A. pullulans followed by inoculation of the pathogens. Our results demonstrate that A. pullulans is an effective biocontrol agent to control strawberry diseases caused by fungal pathogens and can be an effective alternative to chemical-based fungicides.

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First Report of Root Rot Caused by Macrophomina phaseolina on Atractylodes lancea in China

Plant Disease ◽

10.1094/pdis-02-20-0259-pdn ◽

2020 ◽

Vol 104 (11) ◽

pp. 3081-3081

Author(s):

Lin Cai ◽

Yongzhi Zhang ◽

Hancheng Wang ◽

Chen Xu ◽

Xianchao Sun

Keyword(s):

Root Rot ◽

Macrophomina Phaseolina ◽

First Report ◽

Atractylodes Lancea

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First report of Berkeleyomyces basicola causing mango root rot and decline in India

Plant Disease ◽

10.1094/pdis-10-20-2133-pdn ◽

2020 ◽

Author(s):

Prabhat Kumar Shukla ◽

Tahseen Fatima ◽

Nidhi Kumari

Keyword(s):

Root Rot ◽

Fungal Pathogens ◽

Mangifera Indica ◽

Uttar Pradesh ◽

Its2 Region ◽

Mature Trees ◽

Ceratocystis Fimbriata ◽

First Report ◽

Rdna Its2 ◽

Mango Tree

Mango wilt has been a serious constraint in mango (Mangifera indica L.) production in several countries including India (Shukla et al. 2018). Although, several fungal pathogens have been reported associated with the disease, species of Ceratocystis, Verticillium and Lasiodiplodia have been found predominantly responsible for the wilt (Shukla et al. 2018). A twenty-seven-year old mango tree cv. Dashehari at Rehmankhera, Lucknow, Uttar Pradesh, India suffered sudden wilt (Fig. 1A) during February 2020. Though, symptoms were similar to Ceratocystis wilt, no gummosis was observed on trunk or branches which occurred in the majority of Ceratocystis fimbriata infected trees. The infected roots of the wilted tree exhibited dark brown to black discoloration in woody portions (Fig. 1B). Severely affected roots were completely rotten. Similar symptoms of root infection were observed in an additional 16 declining trees within an orchard of 120 trees total (Fig. 2). The infected hard wood samples from live roots of 16 declining and one wilted trees were utilized for isolation by placing stem tissue of discolored and normal colored tissue on surface sterilized fresh carrot discs placed in a moisture chamber (Fig. 1C) for 10 days. Out of 17 tree samples, isolates of Berkeleyomyces basicola (Berk. & Broome) W.J. Nel, Z.W. de Beer, T.A. Duong, M.J. Wingf. (Nel et al. 2018) obtained from 1 wilted and 9 declining trees were transferred to and maintained in pure culture on potato dextrose agar. Isolates were grown for 7 to 10 days at 23±1 °C temperature in the dark. The isolates were characterized by a greyish black compact mycelial colony (Fig. 1D). Two types of spores, endoconidia (phialospores) and chlamydospores (aleuriospores or amylospores) were observed under microscope. The endoconidia were hyaline, cylindrical in shape with 10 to 42 × 3 to 6 μm (n=50) in size (Fig. 1E). Chains of dark colored chlamydospores (3 to 7 spores in chain) of 24 to 52 × 10 to 12 μm (n=50) size were apparent (Fig. 1E&F). Molecular identification of the fungus isolated from the wilted tree was established by amplifying the ITS1-5.8 rDNA-ITS2 region of fungal genomic DNA and the set of ITS primers (ITS 1 and ITS4) (White et al. 1990) followed by sequencing. The sequence has been submitted to the NCBI database vide accession number MT786402. The present isolate (MT786402) shared >99 percent nucleotide similarity with other B. basicola isolates. The phylogenetic tree was constructed using the ITS1-5.8 rDNA-ITS2 sequences of other B. basicola isolates and other Thielaviopsis spp., C. fimbriata, Chalaropsis thielavioides through neighbor joining method using MEGAX software (Fig. 3) (Kumar et al. 2018). The present isolate formed a distinct cluster along with other B. basicola isolates in a separate clade. Koch's postulate was performed under a transparent polycarbonate sheet roof net house at 14.4 and 42.2 °C minimum and maximum temperatures, respectively. A 100 ml macerated culture suspension consisting of 1000 chlamydospores and endoconidia per ml suspension was inoculated in the rhizosphere of mango seedlings planted in sterilized soil filled in earthen pots, using ten replicates for inoculated and uninoculated plants. Symptoms of necrotic root tissue were observed 90 days after inoculation and were consistent with those observed in the field. The same fungus was re-isolated from infected roots and identity was confirmed. All control plants remained symptom-free and B. basicola was not isolated from the roots. Thus, we conclude that B. basicola is capable of causing root rot disease of mango. To the best of our knowledge this is the first report of B. basicola causing mango root rot and decline across the globe, hitherto unreported. The extent of the root necrosis symptoms associated with mature mango trees demonstrates the potential virulence of B. basicola, although its pathogenicity risk on healthy mature trees is still unknown. However, the possibility of severe losses to the mango industry in world number one mango producer country, India cannot be ruled out, if found widespread.

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First Report of a Phytopythium litorale Species Causing Crown and Root Rot on Rhododendron pulchrum in China

Plant Disease ◽

10.1094/pdis-04-21-0830-pdn ◽

2021 ◽

Author(s):

Yaxing Li ◽

Yangfan Feng ◽

Cuiping Wu ◽

Junxin Xue ◽

Binbin Jiao ◽

...

Keyword(s):

Root Rot ◽

Morphological Characters ◽

Morphological Features ◽

Crown Rot ◽

Sterile Water ◽

First Report ◽

Inoculation Method ◽

Platanus Orientalis ◽

Crown And Root Rot ◽

Root Tissues

During a survey of pathogenic oomycetes in Nanjing, China from June 2019 to October 2020, at least ten adjacent Rhododendron pulchrum plants at a Jiangjun Mountain scenic spot showed symptoms of blight, and crown and root discoloration . Symptomatic root tissues collected from three 6-year-old plants were rinsed with water, cut into 10-mm pieces, surface sterilized with 70% ethanol for 1 min, and plated onto 10% clarified V8 PARP agar (cV8A-PARP) containing pimaricin (20 mg/liter), ampicillin (125 mg/liter), rifampicin (10 mg/liter), and pentachloronitrobenzene (20 mg/liter). Four Pythium-like isolates were recovered after three days of incubation at 26°C, and purified using hyphal-tipping. Ten agar plugs (2×2 mm2) of each isolate were grown in 10 mL of 10% clarified V8 juice (cV8) in a 10 cm plate at 26°C for 3 days to produce mycelial mats, and then the cV8 was replaced with sterile water. To stimulate sporangial production, three to five drops of soil extract solution were added to each plate. Sporangia were terminal, ovoid to globose, and the size is 24 to 45.6 (mean 34.7) (n=10.8) in length x 23.6 to 36.0 (mean 29.8) (n=6.2) in width. Gametangia were not observed in cV8A or liquid media after 30 days. For colony morphology, the isolates were sub-cultured onto three solid microbial media (cV8A-PARP, potato dextrose agar, corn meal agar) . All isolates had identical morphological features in the three media. Complete ITS and partial LSU and cox2 gene regions were amplified using primer pairs ITS1/ITS4, NL1/NL4, and FM58/FM66 , respectively. The ITS, LSU, and cox2 sequences of isolate PC-dj1 (GenBank Acc. No. MW205746, MW208002, MW208003) were 100.00% (936/936 nt), 100.00% (772/772 nt), and 99.64% (554/556 nt) identical to those of JX985743, MT042003, and GU133521, respectively. We built a maximum-likelihood tree of Phytopythium species using the concatenated dataset (ITS, LSU, cox2) to observe interspecific differences. Based on the morphological characters and sequences, isolate PC-djl was identified as Phytopythium litorale . As the four isolates (PC-dj1, PC-dj2, PC-dj3 and PC-dj4) tested had identical morphological characters and molecular marker sequences, the pathogenicity of the representative isolate, PC-dj1, was tested using two inoculation methods on ten one-year-old R. pulchrum plants. For the first inoculation method, plants were removed from the pot, and their roots were rinsed with tap water to remove the soil. Each of these plants was placed in a glass flask containing 250 mL of sterile water and 10 blocks (10 x 10 mm2) of mycelial mats harvested from a three-day-old culture of P. litorale, while the other plant was placed in sterile water as a control, and incubated at 26°C. After three days, symptoms including crown rot, root rot and blight was observed on the inoculated plants whereas the control remained asymptomatic. For the second inoculation method, ten plants were dug up to expose the root ball. Ten three-day-old cV8A plugs (5×5 mm2) from a PC-dj1 culture or sterile cV8A plugs were evenly insert into the root ball of a plant before it was planted back into the original pots. Both plants were maintained in a growth chamber set at 26°C with a 12/12 h light/dark cycle and irrigated as needed. After 14 to 21 days, the inoculated plant had symptoms resembling those in the field , while the control plant remained asymptomatic. Each inoculation method was repeated at triplicate and the outcomes were identical. Phytopythium isolates with morphological features and sequences identical to those of PC-dj1 were recovered from rotted crown and root tissues of all inoculated plants. Previously, P. litorale was found causing diseases of apple and Platanus orientalis in Turkey, fruit rot and seedling damping-off of yellow squash in southern Georgia, USA. This is the first report of this species causing crown and root rot on R. pulchrum, an important ornamental plant species in China. Additional surveys are ongoing to determine the distribution of P. litorale in the city of Nanjing.

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First Report of Charcoal Rot in Tomato Caused by Macrophomina phaseolina (Tassi) Goid. From Pakistan

Plant Disease ◽

10.1094/pdis-10-17-1663-pdn ◽

2018 ◽

Vol 102 (7) ◽

pp. 1459 ◽

Cited By ~ 2

Author(s):

S. Hyder ◽

A. S. Gondal ◽

R. Ahmed ◽

S. T. Sahi ◽

A. Rehman ◽

...

Keyword(s):

Macrophomina Phaseolina ◽

Charcoal Rot ◽

First Report

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Application of Mycorrhizae for Controlling Root Diseases of Sesame

Journal of Plant Protection Research ◽

10.2478/v10045-011-0058-0 ◽

2011 ◽

Vol 51 (4) ◽

pp. 355-361 ◽

Cited By ~ 15

Author(s):

El-Sayed Ziedan ◽

Ibrahim Elewa ◽

Mostafa Mostafa ◽

Ahmed Sahab

Keyword(s):

Root System ◽

Seed Yield ◽

Root Rot ◽

Fungal Pathogens ◽

Arbuscular Mycorrhizae ◽

Trichoderma Viride ◽

Macrophomina Phaseolina ◽

Morphological Characters ◽

Va Mycorrhizae ◽

Root Diseases

Application of Mycorrhizae for Controlling Root Diseases of Sesame Vesicular arbuscular mycorrhizae fungi (VAM) was evaluated as a biotic agent for controlling wilt and root-rot diseases of sesame caused by Fusarium oxysporum f. sp. sesami (Zap.) Cast and Macrophomina phaseolina (Moubl) Ashby pathogens can infect sesame plant at any growth stage causing considerable losses of seed yield. Spores of VA mycorrhizae fungi (Glomus spp.) were collected from the soil around the root systems of sesame plants then propagated on roots of Suddan grass (Sorghum vulgare var. sudanese). Under green house and field conditions, two hundreds sporocarps of Glomus spp. were added as a soil drench beside the sesame plant. Glomus spp. (VA mycorrhizae) significantly reduced wilt and root-rot incidence of sesame plants. Lums spp. (VA mycorrhizae) also significantly increased plant morphological characters such as plant height, number of branches and number of pods for each plant. Application of Glomus spp. to protect sesame plants by colonizing the root system, significantly reduced colonization of fungal pathogens in sesame rhizosphere as well as pathogenic activity of fungal pathogens increased lignin contents in the sesame root system were also observed. Furthermore, mycorrhizae treatment provided selective bacterial stimulation for colonization on sesame rhizosphere. These bacteria belonging the Bacillus group showed highly antagonistic potential to fungal pathogens. Application of mycorrhizae together with other biocontrol agent such as Trichoderma viride or Bacillus subtilis significantly effected than individual treatments for controlling these diseases incidences and increasing morphological characters and seed yield of sesame.

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