Fungal Biological Control Research Articles

Evaluation of the Entomopathogenic Fungus Beauveria bassiana on Different Stages of Phlebotomus papatasi (Diptera: Psychodidae), Vector of Zoonotic Cutaneous Leishmaniasis in Iran.

Zoonotic cutaneous leishmaniasis is a major public health problem in Iran with the main vector of Phlebotomus papatasi. The use of entomopathogenic fungi for biological control of the vector is a potential substitute for the current methods which are being used. The purpose of the current study was to assess the virulence of two local isolates of Beauveria bassiana (OZ2 and TV) against Ph. papatasi. To perform the bioassay test, fungal suspensions were applied for every stage of the sand fly life cycle. The mortality rate, longevity, and number of eggs laid were determined. Also, the probability of fungal survival on the surface of rodent's body was assessed. The longevity of infected adult sand flies with both isolates of B. bassiana was significantly lower (P< 0.05) in comparison to the negative control. The estimated Lethal concentration 50 (LC50) values for adult female and male sand flies treated with OZ2 isolate were 1.4×106 and 2.2×107 conidia/ml, respectively, while they were 6.8×106 and 2.3×108 conidia/ml for TV isolate, respectively. Both isolates of B. bassiana exhibited nonsignificant mortality rates in sand fly larvae and pupae and fecundity rate (P> 0.05). According to our findings for both isolates, the fungus continued to spread throughout the surface of the rodent's body for 144 hours after spraying. The current study demonstrated that both isolates of B. bassiana have considerable biological control capacity against adult sand flies.

Virulência de fungos entomopatogênicos sobre larvas de Lepidoptera: Noctuidae

ABSTRACT Currently, agricultural cropping systems have adopted integrated pest management (IPM) as a successful model for pest control. The use of entomopathogenic fungi in IPM has increased because of their great potential for reducing arthropod pest populations without causing harm to human health and ecosystems. Beauveria bassiana and Metarhizium anisopliae stand out among the most used fungi in biological control, with many isolates commercialized worldwide. Helicoverpa armigera is an agriculturally important pest in Brazil and worldwide, causing damage to several crops. In this context, the objective of this study was to evaluate the biological control potential of Beauveria bassiana, Metarhizium anisopliae, and M. rileyi on H. armigera. The results indicated that the entomopathogenic fungi B. bassiana (strain ESALQ PL63), M. anisopliae (strain ESALQ E9), and M. rileyi (strain UFMS 03), applied using different methods (direct application and dry film) and concentrations (1 × 107, 1 × 108, and 1 × 109 conidia mL-1), resulted in low mortality and no virulence in first-, third-, and fifth-instar larvae of H. armigera. The death of all individuals subjected to treatment with B. bassiana (strain ESALQ PL63) was confirmed by conidiogenesis. Considering the importance of H. armigera as an agricultural pest and the biodiversity of entomopathogenic fungi in Brazil, further investigations on the virulence of fungal strains are necessary to improve the integrated management of lepidopteran pests through microbial control, explore the potential of new strains, and understand the relationships between microorganisms and host defense mechanisms.

A biobased superabsorbent formulation for above-ground application of a new entomophthoralean fungus for biological psyllid pest control

Entomophthoralean fungi have long been recognized as promising candidates for biological insect pest control. However, due to technical challenges, no preparation based on these fungi has been established for practical use so far. Low water availability is a key limiting factor of conidial discharge and germination. In the present study, sporulation of psyllid-pathogenic entomophthoralean fungus Pandora cacopsyllae Eilenberg, Keller and Humber (Entomophthorales Entomophthoraceae) was not observable under reduced water activity (aW ≤ 0.97). To support sporulation of encapsulated P. cacopsyllae hyphae from submerged culture under low humidity conditions in above-ground applications in field, we developed a novel paste-type formulation containing biobased superabsorbents, which retained water for a prolonged time period. In co-application with the superabsorbent formulation, the otherwise fast-drying capsules were kept sufficiently moist for sporulation for at least six days in laboratory trials at low humidity below 40%. Using the new formulation, we measured conidial discharge by P. cacopsyllae from the capsules under dry semi-field conditions in summertime by trapping conidia at a vertical distance of up to 40 cm from the sporulation source. By considering the cardinal directions, fewer conidia were discharged on the sun-facing side in the east than on the sun-averted side in the west. The developed formulation improved the sporulation efficacy significantly. Since water availability is a limiting factor for many fungal biocontrol agents, the developed formulation has the potential to also improve their efficacy.

Chinee Apple (Ziziphus mauritiana): A Comprehensive Review of Its Weediness, Ecological Impacts and Management Approaches.

Ziziphus mauritiana Lam. (Rhamnaceae) (Chinee Apple, Indian Jujube, or Ber) is a significant woody weed in the drier tropics of northern Queensland, Western Australia, and the Northern Territory. Throughout these regions, its densely formed thickets influence the structure, function, and composition of rangeland ecosystems by outcompeting native pasture species. Despite this, the recent literature is heavily focused on the horticultural value of domesticated Ziziphus species in South Asia (China, India, and Pakistan), particularly its potential for poverty alleviation in arid or semi-arid areas. In fact, there has been comparatively little research undertaken on its invasiveness or associated ecological factors in pastoral contexts. Currently, the management of Z. mauritiana is limited to the application of synthetic herbicides or mechanical clearing operations. There is also considerable interest in the exploitation of host-specific, natural enemies (biological control agents, herbivorous insects, fungi, bacteria, or viruses) for limiting the vigour, competitiveness, or reproductive capacity of Z. mauritiana in northern Australia. The development of a "bioherbicide" in lieu of synthetic counterparts may foster a more resilient coexistence between agricultural systems and the natural environment owing to its reduced environmental persistence and increased target specificity. This review summarises the current literature on the weediness, ecological impacts, and current management of this problematic weed, thereby identifying (i) opportunities for further research and (ii) recommendations for improved management within its invasive range.

Efficiency of the Iraqi Isolates of Beauveria Bassiana &amp; Metarhizium Anisopliae in Controlling the Greater Wax Moth Galleria Mellonella L.

The current study was conducted in the laboratories of the Plant Protection Department/College of Agriculture and Forestry/University of Mosul during the year 2019-2020. The aim of this study was to evaluate the efficiency of the Iraqi isolate of the biological control fungi Beauveria bassian and Metarhizium anisopliaeas chemical pesticides alternatives in controlling different stages of the greater wax moth Galleria mellonella. The results of the biological effect of the fungi Beauveria bassiana and Metarhizium anisopliae on the greater wax moth life stages showed that the cumulative mortality of eggs increased gradually with increasing concentration used. However, Beauveria bassiana was more efficient in achieving higher mortality rates than M. anisopliae in general. The highest cumulative mortality rate for eggs was at the highest concentration (7.5g/l) for both fungi. On the other hand, it was found that the highest mortality rate in wax moth larvae was inB. bassianacombined treatmentwhere spraying the larvae and the feed. The third and fourth larval instars were more sensitive than the sixth and seventh larval instars, which were not affected by the lower concentrations of the pesticide (2.5 and 5 g/L), regardless of pesticide type. The results also showed that the mortality rate in all phases increases with the increase in the post-treatment period. The results of the study indicated the superiority of B. bassiana in all treatments, concentrations and periods after treatment and led to the highest mortality rate compared with using M. anisopliae. The cumulative mortality rate in the greater wax moth was directly proportional to the increase in treatment methods and the increase in concentration and the time period after treatment.

Insecticidal activity of isolated Purpureocillium lilacinum PL1 against whitefly, Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae) on cassava plantations in southern Viet Nam

BackgroundWhitefly Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae) is a plant-damaging insect in tropical and subtropical regions that causes agricultural damage worldwide, including in Viet Nam. The abuse of pesticides derived from chemicals has resulted in the evolution of insect-resistant strains, polluting the environment and threatening human health. Using entomopathogenic fungi (EPF) for biological control is an alternative strategy in integrated pest management. Hence, an attempt was conducted to isolate, characterize and evaluate the efficacy of EPF, Purpureocillium lilacinum against whitefly B. tabaci under laboratory and field conditions.ResultsPurpureocillium lilacinum PL1 (PL1) was isolated from the whitefly B. tabaci cadavers and subsequently identified using morphological study and internal transcribed spacer sequencing. Purpureocillium lilacinum PL1 had effectively grown and sporulated at temperatures ranging from 25 to 35 °C and throughout a broad pH range, which is particularly advantageous against the harsh tropical monsoon climate. Bioassay study indicated that 1 × 107 conidia/ml of P. lilacinum PL1 had a high lethality against the whitefly B. tabaci nymphs in vitro with efficiency was 88.24% after 7 days of treatment. The median lethal concentration (LC50) of P. lilacinum PL1 to B. tabaci after 7 days of treatment was 1.24 × 105 conidia/ml. In field conditions, 1 × 107 conidia/ml of P. lilacinum PL1 lowered the population of B. tabaci nymphs with efficacy was 78.86% after 2 batches, 7 days after treatments.ConclusionThe findings indicated that P. lilacinum PL1 was effective in the biological control of B. tabaci nymphs, which could be a potential alternative to chemical pesticides for pest management.

Effect of Bacillus insecticidal proteins on the Japanese beetle, Popillia japonica (Scarabaeidae)

The Japanese beetle, Popillia japonica, is a minor pest in Japan but has become a serious invasive species in several parts of the world, causing damage in a variety of crops and high costs for its control. Many different methods of control have already been applied, including chemical and cultural measures, as well as mass-trapping. The efficacy of biological control attempts, using parasitoids, nematodes, fungi, or bacteria has also been discussed especially with regard to added value of lower ecological impact. The effect of Bacillus thuringiensis (Bt) treatments is probably attributable to the proteins accumulated in the parasporal body of the bacteria. In this context, a study was conducted to assess the insecticidal activity against P. japonica of the Bt 3 domain non-parasporal body accumulated Cry1Ia protein, and the structurally distant Bt proteins Mpp23Aa and Xpp37Aa. Their activity was tested against P. japonica larvae using a modified leaf-dip protocol, and only the Cry1Ia showed some activity. The results suggest that additional studies on Bacillus proteins are needed for developing new biological control strategies against P. japonica.

Combining entomopathogenic Pseudomonas bacteria, nematodes and fungi for biological control of a below-ground insect pest

Below-ground insect pests are challenging to control because they are hard to target with control measures. Moreover, broad spectrum insecticides are or will soon be banned due to their negative effects on non-target organisms. In this study, we have developed a biological control method for the cabbage maggot Delia radicum (Diptera: Anthomyiidae), a significant pest of Brassicacean crops, based on a consortium of three biocontrol agents (BCAs). We chose the bacterium Pseudomonas chlororaphis because it can be used in a dual strategy against insect pests and fungal plant diseases, and combined it with the nematode Steinernema feltiae and the fungus Metarhizium brunneum that have a long history of commercial use against different pest insects. Our aim was to combine BCAs with different modes of action in order to achieve a stable and reliable biocontrol effect. We first tested double combinations of the bacterium with either the nematode or the fungus for improved potential to kill D. radicum in laboratory assays. We then evaluated the effect of double and triple combinations on D. radicum development and maggot-induced damage on radish bulbs in a series of pot experiments with artificial cabbage maggot infection performed in the greenhouse and outdoors and finally in a field trial with a natural infestation. Our results show that i) insecticidal pseudomonads are highly efficient in D. radicum control, ii) the three BCAs are compatible and neither inhibit each other’s infectiousness nor survival in the soil or on the roots, iii) synergistic effects of Pseudomonas-nematode and Pseudomonas-fungus combinations on maggot killing are possible, and iv) the triple combination reduced both pest survival in greenhouse experiments and maggot-induced damage on radish bulbs in the field by 50% each. The strategy we present here is a promising step forward to a reliable and efficient environmentally friendly biological control method for the cabbage maggot, which can also be adapted to other problematic below-ground pests.

Effect of temperature and pH on growth and sporulation of both Local isolates of biological control fungi Metarhizium anisopliae and Beauveria bassiana

A laboratory study was conducted by using two local isolates of biological control fungi M. anisopliae and B.bassiana that isolated from the soil of citrus orchards that infested with Mediterranean fruit fly Capitata ceratiris in Baghdad to know the effect of four different temperatures included 15, 20, 25 and 30 ° C and four levels of the pH, including 5, 6, 7 and 8 on the growth and sporulation of two local isolates on liquid medium. Results showed that the highest growth of the fungus M. anisopliae was at 20° C, average dry weight was1.19 gm and best sporulation of the fungus at 25°C ,it was 10.3×104 spore/g, while was higher growth and sporulation for B. bassiana at 20 °C , they were 1.11 gm and 2.7 × 104 spore / g, respectively, the results showed that the highest dry weight for M. anisopliae and B.bassiana was at /pH 7,they were 5.9 and 3.38 gm respectively, and the best sporulation for them when the pH5 ,they were 3.9×104 and 3.8×104 spore /g respectively, the isolated fungus B. bassiana surpass in the production of both chitinase and proteinase enzymes depending on decomposition aureole diameter, they were 15.76 and 11.37 cm, respectively, compared to M.anisopliae which amounted 14.17 and 4.36 cm respectively.

Continuous Wheat/Soybean Cropping Influences Soybean Yield and Rhizosphere Microbial Community Structure and Function

Wheat/soybean rotation is an important double-cropping system in the Huang-Huai-Hai plain of China. Continuous soybean cropping could cause soil quality deterioration and plant growth inhibition. However, the effects of continuous wheat/soybean cropping on soybean rhizosphere microbes remain largely unknown. In this study, we compared the soybean yield and rhizosphere soil microbial community between continuous winter wheat/summer soybean (W/S) with two harvests in one year and winter wheat/summer soybean-winter wheat/summer maize (W/S-W/M) with four harvests in two years. The results showed that the soybean yield in the W/S group significantly (p &lt; 0.05) declined within the first two years. The W/S-W/M showed higher soybean yield and soil fertility index than the W/S group. The sequencing results revealed that cropping rotation had a higher impact on the fungal community than the bacterial community. The W/S group showed 22.08–23.01% higher alpha diversity of the fungal community, but the alpha diversity of the bacterial group did not vary significantly in this group. The fungal community composition in the W/S and W/S-W/M groups differed significantly. In the W/S-W/M group, a higher relative abundance of plant growth-promoting fungi (e.g., Mortierella), nematophagous fungi (e.g., Plectosphaerella), and biological control fungi (e.g., Coniothyrium) was observed. In the W/S group, a higher relative abundance of lignocellulose-degrading fungi (e.g., Trechispora, Myceliophthora, Botryotrichum, and Coniochaeta) and pathogenic fungi (e.g., Pyrenochaetopsis and Cyphellophora) was observed. LEfSe analysis demonstrated that Mortierella, Myceliophthora, and Trechispora could serve as crucial biomarkers. Mortierella was positively associated with available P levels and negatively associated with NO3−-N levels and pH while Trechispora showed the opposite trend. The findings of this study could enhance the current understanding of the mechanisms associated with the continuous wheat/soybean cropping obstacles and ensure the sustainability of agricultural production.

Uji Sinergitas Rendaman Tembakau (Nicotiana tabacum L.) dengan Jamur Trichoderma spp. Secara In Vitro dan Potensinya Sebagai Gabungan Biopestisida Alami

Management of plant pests and diseases can prevent crop failure of agricultural commodities. Trichoderma spp. is a type of biological control fungus. Tobacco can be used as a vegetable pesticide. However, the synergy of tobacco and Trichoderma spp. when applied simultaneously in controlling pathogens is not yet known, considering the content of the active compound nicotine in tobacco which has antifungal properties, it is necessary to conduct this study with the aim of knowing the effect of tobacco immersion on the growth of the fungus Trichoderma spp. and if there is no inhibition then both will have the potential as a combination of natural biopesticides. This study used a completely randomized design (CRD). The treatment tried was different concentrations of tobacco soak mixed with PDA as a culture medium for Trichoderma spp. The concentrations tested were 0% (T0, positive control), 5% (T1), 10% (T2), 15% (T3), and 20% (T4). The negative control used a fungicide with the active ingredient mankozeb. Each treatment was repeated 3 times. Colony thickness and color data were observed visually by descriptive method. Meanwhile, data on colony diameter, number of spores, dry weight of mycelium were analyzed by F test, if significantly different, then followed by DMRT test with a confidence level of 5%. Based on research that has been carried out from July-August 2021, the results obtained on PDA media with tobacco soaking content with concentrations of 0% (K+), 5% (T1), 10% (T2), 15% (T3), 20% (T4 ) can be grown with Trichoderma spp., while the media with the addition of synthetic fungicides made from mankozeb is not grown. The difference in concentration showed different growth results and the effective concentration in this research was 15%, because at 20% concentration there was a decrease in spore density and mycelium dry weight.

Time-series gene expression patterns and their characteristics of Beauveria bassiana in the process of infecting pest insects.

Beauveria bassiana has been widely used as an important biological control fungus for agricultural and forest pests, and clarifying the interaction mechanism between B. bassiana and its host will help to better exert the efficacy of the mycoinsecticide. Here, we proposed a novel pattern analysis (PA) method for analyzing time-series data and applied it to a transcriptomic data set of B. bassiana infecting Galleria mellonella. We screened out 14 patterns including 868 genes, which had some characteristics that were not inferior to differentially expressed genes (DEGs). Compared with the previous analysis of this data set, we had three novel discoveries during B. bassiana infection, including overall downregulation of gene expression, the more critical first 24 h, and enrichment of regulatory functions of downregulated genes. Our new PA method promises to be an important complement to DEGs analysis for time-series transcriptomic data, and our findings enrich our knowledge of molecular mechanisms of fungal-host interactions.

MaAts, an Alkylsulfatase, Contributes to Fungal Tolerances against UV-B Irradiation and Heat-Shock in Metarhizium acridum

Sulfatases are commonly divided into three classes: type I, type II, and type III sulfatases. The type III sulfatase, alkylsulfatase, could hydrolyze the primary alkyl sulfates, such as sodium dodecyl sulfate (SDS) and sodium octyl sulfate. Thus, it has the potential application of SDS biodegradation. However, the roles of alkylsulfatase in biological control fungus remain unclear. In this study, an alkylsulfatase gene MaAts was identified from Metarhizium acridum. The deletion strain (ΔMaAts) and the complemented strain (CP) were constructed to reveal their functions in M. acridum. The activity of alkylsulfatase in ΔMaAts was dramatically reduced compared to the wild-type (WT) strain. The loss of MaAts delayed conidial germination, conidiation, and significantly declined the fungal tolerances to UV-B irradiation and heat-shock, while the fungal conidial yield and virulence were unaffected in M. acridum. The transcription levels of stress resistance-related genes were significantly changed after MaAts inactivation. Furthermore, digital gene expression profiling showed that 512 differential expression genes (DEGs), including 177 up-regulated genes and 335 down-regulated genes in ΔMaAts, were identified. Of these DEGs, some genes were involved in melanin synthesis, cell wall integrity, and tolerances to various stresses. These results indicate that MaAts and the DEGs involved in fungal stress tolerances may be candidate genes to be adopted to improve the stress tolerances of mycopesticides.

Effects of various metal ions on the growth of some phytopathogenic and biological control fungi

Effects of various metal ions on the growth of some phytopathogenic and biological control fungi

Endophytic fungi for biological control of whitefly and tomato leaf miner in Tanzania

Tomato whiteflies (Bemisia tabaci) and leaf miners (Tuta absoluta) are devastating pests of tomato (Lycopersicon esculentum). Pest management using broad spectrum synthetic pesticides is discouraged due to harmful effects on human health and the environment. The objective of this study was to assess the potential of endophytic fungi as bioextracts against tomato whiteflies and leaf miners, as an alternative to synthetic insecticides in Tanzania. The study was done using morphological and molecular techniques, during January 2019 to February 2020 in Arusha region in Tanzania. Three endophyte isolates from pyrethrum (Chrysanthemum cinerariifolium) and lemon grass (Cymbopogon citratus) were identified with resemblance to members of Fusarium sp and Altenaria sp, by 90 and 82 % similarity, respectively; based on phylogenetic clustering patterns and macro- and micro-morphological characteristics. Bioextracts from endophytes of lemon grass leaves (Elg1); and pyrethrum flowers (Epf1) and leaves (Epl1), showed significant repellency properties (F0.05 (df, 15) = 27.052, P = 0.0001) on whiteflies by 54, 76 and 36%, respectively. They also caused significant lethality (F0.05 (df, 11) = 59.559, P = 0.0001) of tomato leaf miner larvae and whiteflies (F0.05 (df, 11) = 53.600, P = 0.0001). The underlying effect was attributed to possession of flavonoid and total phenolics as active ingredients in the bioextracts. This was commensurate to the levels flavonoid and total phenolic contents, which were considerably more in bioextracts of lemon grass and pyrethrum flower (F0.05 (df, 8) = 10.35, P = 0.0114) and (F0.05 (df, 8) = 40.84, P = 0.0003, respectively), than in pyrethrum leaves.

Patents on Endophytic Fungi for Agriculture and Bio- and Phytoremediation Applications.

Plant endophytic fungi spend all or part of their lives inside host tissues without causing disease symptoms. They can colonize the plant to protect against predators, pathogens and abiotic stresses generated by drought, salinity, high concentrations of heavy metals, UV radiation and temperature fluctuations. They can also promote plant growth through the biosynthesis of phytohormones and nutrient acquisition. In recent years, the study of endophytic fungi for biological control of plant diseases and pests has been intensified to try to reduce the ecological and public health impacts due the use of chemicals and the emergence of fungicide resistance. In this review, we examine 185 patents related to endophytic fungi (from January 1988 to December 2019) and discuss their applicability for abiotic stress tolerance and growth promotion of plants, as agents for biocontrol of herbivores and plant pathogens and bio- and phytoremediation applications.

Incremento en la mortalidad del hongo entomopatógeno Metarhizium anisopliae al aplicar un campo eléctrico durante la conidiación

The effects of an electric field on conidia production by Metarhizium anisopliae in solid state culture were determined. A 450-mL electrochemical cell (EC) with titanium ruthenium-oxide coated electrodes and packed with a mixture of rice:corn stubble, was inoculated with 1x106 conidia (g of initial dry support)-1 and incubated for 8 days (30oC). Four days after starting the culture, a current density of 0.09 mA/cm2 was applied for 24 h. The moisture kept constant (75%), with and without electric field. With electric field, conidiation (4.9x108 ± 3.7x107 conidia (g of initial dry support)-1) did not show significant differences, but their viability and germination (67 and 45%, respectively) were lower than in the non-perturbated conidia. Total mortality of Tenebrio molitor larvae provoked by conidia produced in presence of the electric field was 40% higher compared to that provoked by the conidia control. The study showed that the application of electric field improving the conidial infectivity. This new approach is susceptible to be optimized to other fungi for biological control with the purpose of improving field performance and further investigations on the modification of cellular mechanisms by the electric field stimuli.

Phylogenetic Relationships between Phlebiopsis gigantea and Selected Basidiomycota Species Inferred from Partial DNA Sequence of Elongation Factor 1-Alpha Gene

Phlebiopsis gigantea (Fr.) Jülich has been successfully used as a biological control fungus for Heterobasidion annosum (Fr.) Bref., an important pathogen of pine and spruce trees. The P. gigantea species has been known for many years, but our understanding of the relationship between various isolates of this fungus has been substantially improved through the application of DNA sequence comparisons. In this study, relationships between P. gigantea and selected Basidiomycota species was determined, based on elongation factor 1-alpha (EF1α) partial DNA sequence and in silico data. A total of 12 isolates, representing the most representatives of P. gigantea, with diverse geographic distributions and hosts, were included in this study. Phylogenetic trees generated for sequences obtained in this research, grouped the European taxa of P. gigantea and partial sequence of the genome deposed in NCBI database, in a strongly supported clade, basal to the rest of the strains included in the study. P. gigantea isolates originating from Poland, Finland, Sweden, Great Britain and partial sequence of genome formed a monophyletic group. Within this group, isolates of P. gigantea constituted two subclades, showing their partial difference like the two SNPs (single nucleotide polymorphisms) between one and the rest of isolates. The intron and exon relationships among P. gigantea isolates were moreover resolved. The results obtained using the EF1α region should be useful in the selection of more efficient P. gigantea isolates for limiting forest tree root pathogens.

Granular Bioactive Formulation of Trichoderma viride and Arbuscular Mycorrhizal Fungi for Biological Control of Cumin Wilt Disease

Cumin wilt caused by Fusarium oxysporum f. sp. cumini is the most destructive abundant disease, limiting the cumin production in Egypt. The objective of this study was to evaluate the efficacy of granular bioactive formulation of Trichoderma viride (GBTV) and arbuscular mycorrhizal fungi (AM) for biological control of cumin wilt disease. Ten Trichoderma species were isolated from the rhizosphere of healthy cumin plants and tested in dual culture assay against the growth of F. oxysporum. Trichoderma viride TC40, T. hamatum and T. koningii recorded the highest reduction in the growth of the target pathogen. Under greenhouse conditions, use of AM+GBTV formulation minimized F. oxysporum incidence and increased plant survival percentages. GBTV treatment alone came the second when compared to infected control. The greatest proportional increases in cumin plant growth were elicited by GBTV formulation and/or AM treatments. The highest level of mycorrhizal root colonization was noticed in the presence or absence of thepathogen. The biochemical parameters of the infected plants with AM or by GBTV treatment showed a pronounced increase in the plant content of total phenols, peroxidase and polyphenoloxidase activities. Under field conditions, AM+GBTV treatment highly reduced disease incidence of wilt symptoms and increased plant survival as equal as chemical fungicide. It also improved plant growth parameters and yield. The suggested formula is highly recommended for Fusarium wilt management and yield production of cumin plants.

Application of Agriculturally Important Microorganisms for Biocontrol of Root Rot Infection of Sugar Beet

The roots rot of sugar beet caused by the soil-borne phytopathogenic fungi genera Fusarium and Alternaria are serious causes yield loss in the world. In this study, the antagonistic cellulolytic bacteria were isolated from the rhizosphere of sugar beet plants. The cellulase, antifungal, and growth-promoting activities of strains were examined, and one strain Bacillus cytaseus C-82 was selected. When C-82 was tested for its fungal inhibition and biological control activity under field conditions against root rot of sugar beet, it significantly reduced the disease and increased sugar beet yields by 30–34 c/ha relative to the untreated control plants.