Strains Of Metarhizium Anisopliae Research Articles

Influence of Metarhizium anisopliae (IMI330189) and Mad1 protein on enzymatic activities and Toll-related genes of migratory locust.

Efficacy of Metarhizium anisopliae strain (IMI330189) and Mad1 protein alone or in combination by feeding method to overcome immune-related enzymes and Toll-like pathway genes was investigated in migratory locust. M. anisopliae (IMI330189) is a potent and entomopathogenic fungal strain could be effectively used against insect pests. Similarly, Mad1 protein adheres to insect cuticle, causing virulence to insects. We confirmed maximum 55% of mortality when M. anisopliae (IMI330189) and Mad1 was applied in combination. Similarly, increased PO activity was observed in locust with combined dose of Mad1 + IMI330189 whereas PO, POD, and SOD activities reduced using Mad1 independently. Four Toll-like signaling pathway genes (MyD88, Cactus, Pelle, and CaN) were investigated from midgut and body of the migratory locust after 72h of treatments. Subsequently, the expression of MyD88 in the midgut and body significantly decreased with the application of Mad1 and Mad1 + IMI330189. Performance of these treatments was absolutely non-consistent in both parts of insects. Meanwhile, IMI330189 significantly raised the expression of Cactus in both midgut and body. However, the combined treatment (Mad1 + IMI330189) significantly reduced the Cactus expression in both body parts. Pelle expression was significantly increased in the midgut with the application of independent treatment of Mad1 and IMI330189 whereas the combined treatment (Mad1 + IMI330189) suppressed the Pelle expression in midgut. Its expression level was absolutely higher in body with the application of IMI330189 and Mad1 + IMI330189 only. On the other hand, Mad1 significantly increased the expression of CaN in midgut. However, all three treatments significantly affected and suppressed the expression of CaN gene in body of locust. This shows that the applications of M. anisopliae and Mad1 protein significantly affected Toll signaling pathway genes, which ultimately increased level of susceptibility of locust. However, their effect was significantly different in both parts of locust which recommends that the Toll-related genes are conserved in midgut instead of locust body.

Phenotypic and molecular analysis of Mexican Metarhizium anisopliae strains

Metarhizium anisopliae is an anamorphic fungus widely studied due to its use as a biological control agent. In Mexico, it is mainly used as an integrated management strategy to control populations of spittlebugs (Hemiptera: Cercopidae) that affect sugarcane fields and cattle pastures. In this study, 13 strains isolated from Aeneolamia spp. (Hemiptera: Cercopidae) from the main areas of sugarcane production of Mexico and 11 reference strains of Metarhizium from different insect hosts and geographic origins were evaluated based on their conidial dimensions, thermotolerance at 15, 25, 30, and 35 oC, random amplification of polymorphic DNA (RAPD) patterns using a combined analysis with 14 different oligonucleotides and diversity estimators, and a phylogenetic analysis with the ribosomal RNA internal transcribed spacer (ITS) region. All strains used in this study showed typical morphological characteristics corresponding to M. anisopliae and were able to grow at 25 and 30 oC with restricted growth at low (15 oC) and high temperatures (35 oC). Polymorphism analysis clustered all strains from Aeneolamia sp. in one welldefined group with low variability among them. Phylogenetic relationships based on nuclear ribosomal ITS region sequences recovered a subclade within M. anisopliae formed by 10 of the Mexican strains.

Isolation, Identification, and Virulence of a New Metarhizium anisopliae Strain on the German Cockroach

The efficacy of a new and highly virulent Metarhizium anisopliae (Hypocreales: Clavicipitaceae) strain was evaluated against Blattella germanica (L.) (Blattaria: Blattellidae) in the laboratory; this strain was obtained and purified from field-collected Eupolyphaga sinensis cadavers. The status of this fungus as a new and genetically distinct species was supported by ITS sequence comparisons. The new strain was compared with other M. anisopliae isolates and was found to be highly infectious and virulent against B. germanica. The virulence of this new strain against different instars of male and female cockroaches at five conidia concentrations (1 × 105, 1 × 106, 1 × 107, 1 × 108, and 1 × 109 conidia/ml) was evaluated in vitro, and the mortality (measured as lethal concentrations, LC50) was determined. According to the pathogenicity test, M. anisopliae isolate EB0732 produced 100% mortality of one- to three-instar nymph (LC50 = 0.37 × 105conidia/ml) and 78.33% mortality of adult female (LC50 = 1.39 × 107 conidia/ml) at 15 d post-inoculation at a concentration of 1 × 109 conidia/ml. There was an overall significant effect on mortality between the age and sex of B. germanica. A M. anisopliae susceptibility test showed that the survival rate of cockroaches after treatment with topical applications and mixed infection was lower than per os. These studies shed light on a valuable integrated pest management against the German cockroach.

Pathogen-produced catalase affects immune priming: A potential pathogen strategy

Immune priming in invertebrates occurs when the first contact with a pathogen/parasite enhances resistance after a second encounter with the same strain or species. Although the mechanisms are not well understood, there is evidence that priming the immune response of some hosts leads to greater pro-oxidant production. Parasites, in turn, might counteract the host attack with antioxidants. Virulent pathogen strains may therefore mask invertebrate immune priming. For example, different parasite species overexpress catalase as a virulence factor to resist host pro-oxidants, possibly impairing the immune priming response. The aim of this study was firstly to evaluate the specificity of immune priming in Tenebrio molitor when facing homologous and heterologous challenges. Secondly, homologous challenges were carried out with two Metarhizium anisopliae strains (Ma10 and CAT). The more virulent strain (CAT) overexpresses catalase, an antioxidant that perhaps impairs a host immune response mediated by reactive oxygen species (ROS). Indeed, T. molitor larvae exhibited better immune priming (survival) in response to the Ma10 than CAT homologous challenge. Moreover, the administration of paraquat, an ROS-promoting agent, favoured survival of the host upon exposure to each fungal strain. We propose that some pathogens likely overcome pro-oxidant-mediated immune priming defences by producing antioxidants such as catalase.

Establishment of Metarhizium anisopliae (Metchnikoff) sorokin as endophyte in maize and sorghum

Glasshouse experiments were conducted to establish an indigenous soil-derived strain of Metarhizium anisopliae (ICAR-NBAIR Ma-35) as endophyte in maize and sorghum by artificial inoculation through foliar spray of conidial suspension. Colonization of M. anisopliae were studied at 15, 30, 45, 60, 75 and 90 Days After Treatment (DAT) in stem and leaf tissues of maize and sorghum by plating technique and PCR method. Metarhizium anisopliae showed variation with regard to the extent of colonization in stem and leaf tissues of maize and sorghum. In maize, colonization was observed at 30DAT in stem and 30-45DAT in leaf. In sorghum, colonization of M. anisopliae was observed during 15-60DAT in stem and 15-75DAT in leaf indicating longer persistence compared to maize. Colonization of M. anisopliae was observed in young growing stem tips and leaves (unsprayed) indicating the internal spread of M. anisopliae in maize and sorghum plants. M. anisopliae was not detected in the untreated stem and leaf tissues of maize and sorghum. The positive results of colonization of M. anisopliae in maize and sorghum stem/leaf tissues observed in plating technique were confirmed by the PCR amplification.

Expression, purification, and characterization of a novel acid phosphatase that displays protein tyrosine phosphatases activity from Metarhizium anisopliae strain CQMa102.

The protein tyrosine phosphatase (PTPase) plays an important role in insect immune system. Our group has purified a type of acid phosphatase that could specifically dephosphorylate trans-Golgi p230 in vitro. In order to study this phosphatase further, we have identified and cloned the phosphatase gene from a locust specific Metarhizium anisopliae Strain CQMa102. The CQMa102 phosphatase was expressed in Pichia pastoris to verify its protease activity. The molecular weight (MW) and the isoelectric point (pI) of the phosphatase were about 85kDa and 6.15, respectively. Substrate specificity evaluation showed that the purified enzyme exhibited high activity on O-phospho-L-tyrosine. At its optimal pH of 6.5 and optimum temperature of 70°C, the protein showed the highest activity respectively. It can be activated by Ca2+, Mg2+, Mn2+, Ba2+, Co2+ and phosphate analogs, but inhibited by Zn2+, Cu2+, fluoride, dithiothreitol, β-mercaptoethanol and N-ethylmaleimide.

Entomopathogenic fungi and nematodes against larvae of the chestnut weevil, Curculio elephas (Coleoptera: Curculionidae): a laboratory evaluation

ABSTRACTPest control in chestnut orchards is mainly achieved by chemicals, but there is growing focus on the potential use of biological control agents. The larval susceptibility of the chestnut weevil Curculio elephas L. (Coleoptera: Curculionidae) to different strains/species of entomopathogenic fungi and nematodes was evaluated in laboratory by soil cup bioassays. In the experiments with fungi, a wild strain of Metarhizium anisopliae caused the highest larval mortality (about 90%) compared with a commercial and a wild strain of Beauveria bassiana (80% and 77% respectively). Regarding nematodes, the commercial strain of Heterorhabditis bacteriophora was more effective in the control of chestnut larvae (77% insect mortality) than Steinernema carpocapsae (43%).

Development of Metarhizium anisopliae as a Mycoinsecticide: From Isolation to Field Performance.

A major concern when developing commercial mycoinsecticides is the kill speed compared to that of chemical insecticides. Therefore, isolation and screening for the selection of a fast-acting, highly virulent entomopathogenic fungus are important steps. Entomopathogenic fungi, such as Metarhizium, Beauveria, and Nomurea, which act by contact, are better suited than Bacillus thuringiensis or nucleopolyhedrosis virus (NPV), which must be ingested by the insect pest. In the present work, we isolated 68 Metarhizium strains from infected insects using a soil dilution and bait method. The isolates were identified by the amplification and sequencing of the ITS1-5.8S-ITS2 and 26S rDNA region. The most virulent strain of Metarhizium anisopliae was selected based on the median lethal concentration (LC50) and time (LT50) obtained in insect bioassays against III-instar larvae of Helicoverpa armigera. The mass production of spores by the selected strain was carried out with solid-state fermentation (SSF) using rice as a substrate for 14 days. Spores were extracted from the sporulated biomass using 0.1% tween-80, and different formulations of the spores were prepared. Field trials of the formulations for the control of an H. armigera infestation in pigeon peas were carried out by randomized block design. The infestation control levels obtained with oil and aqueous formulations (78.0% and 70.9%, respectively) were better than the 63.4% obtained with chemical pesticide.

Chronic effects and horizontal transmission of Metarhizium anisopliae strain QS155 infection in the sweet potato weevil, Cylas formicarius (Coleoptera: Brentidae)

Cylas formicarius is a major pest of sweetpotato in Papua New Guinea. In this study, the chronic effects of infection with Metarhizium anisopliae strain QS155 in adult C. formicarius were investigated. Female fecundity was significantly reduced in treatments where females were infected directly and maintained in pairs with either infected or uninfected males, and to a statistically equivalent level (51%) when initially uninfected females were caged with infected males. A significant increase in the proportion of eggs left exposed outside the host plant occurred in response to either direct or indirect maternal exposure to M. anisopliae. The hatchability of eggs fully enclosed by host plant tissues was also significantly reduced by exposure of females to M. anisopliae; together these factors led to a total decline in reproductive success of 69%–80%. These results demonstrate that a conidial concentration of M. anisopliae strain QS155 well below that required for rapid host mortality adversely affects reproductive and behavioural traits in adult C. formicarius. When groups of C. formicarius were held together for 12days after either all males, all females, or just a proportion of males were initially inoculated, clear evidence of horizontal transmission was obtained. In both males and females mortality arising from horizontal transmission was statistically equivalent to mortality levels when individuals of the same sex had been directly infected. Exposure to sporulating adult cadavers also caused significant mortality to uninfected SPW adults, and M. anisopliae was recovered from weevils that died following exposure to infected cadavers.

Application of the entomogenous fungus, Metarhizium anisopliae, for leafroller (Cnaphalocrocis medinalis) control and its effect on rice phyllosphere microbial diversity.

Microbial pesticides form critical components of integrated pest management (IPM) practices. Little, however, is known regarding the impacts of these organisms on the indigenous microbial community. We show that Metarhizium anisopliae strain CQMa421 was highly effective in controlling the rice leafroller, Cnaphalocrocis medinalis Guenee. In addition, M. anisopliae distribution and its effects on phyllosphere microbial diversity after application in field trials were investigated. Phylloplane specific distribution of the fungus was observed over time, with more rapid declines of M. anisopliae CFUs (colony-forming units) seen in the top leaf layer as compared to lower layers. Application of the fungus resulted in transient changes in the endogenous microbial diversity with variations seen in the bacterial observed species and Shannon index. Notable increases in both parameters were seen at 6-day post-application of M. anisopliae, although significant variation within sample replicates for bacteria and fungi were noted. Application of M. anisopliae increased the relative distribution of bacterial species implicated in plant growth promotion and organic pollutant degradation, e.g., Methylobacterium, Sphingobium, and Deinococcus. These data show minimal impact of M. anisopliae on endogenous microbial diversity with transient changes in bacterial abundance/diversity that may result in added benefits to crops.

Efficacy of <em>Metarhizium anisopliae</em> in the control of the horn fly, <em>Haematobia irritans</em> (<em>Diptera: Muscidae</em>), under natural infestation conditions

Veterinaria Mexico OA ISSN: 2448-6760 Cite this as: Cruz Vazquez C, Carvajal Marquez J, Lezama Gutierrez R, Vitela Mendoza I, Angel Sahagun CA. Efficacy of Metarhizium anisopliae in the control of the horn fly, Haematobia irritans ( Diptera: Muscidae ), under natural infestation conditions. Veterinaria Mexico OA. 2017;4(2). doi: 10.21753/vmoa.4.2.384 . The aim of this study was to determine the efficacy of the entomopathogenic fungus, Metarhizium anisopliae strain 134 (Ma134), for dairy cattle naturally infested with Haematobia irritans (L.) An aqueous formulation of 1 x 10 8 conidia/ml was applied by aspersion on a group of eight cows every seven days for a total of four applications, while a control group was sprayed with the same solution without conidial content. The degree of horn fly infestation was estimated daily in both groups by the direct count of adult flies found resting or feeding on the animals, and Abbott’s formula was used to calculate the effectiveness of the formulation. The Ma134 formulation resulted in a 68.6 % reduction of the fly infestation during the study period, and a significant reduction was observed from the first week post-application ( p < 0.05). The results show that the Ma134 formulation is effective in reducing infestations of horn fly, H. irritans , on dairy cattle under natural conditions. Thus, the fungus, Ma134, can be considered a candidate for biological control for the integrated management of H. irritans . Figure 1. Infestation index of horn flies, Haematobia irritans , on cows treated with the aqueous formulation of Ma134

Identification of double-stranded RNA viruses in Brazilian strains of Metarhizium anisopliae and their effects on fungal biology and virulence

Brazil is the leading country in the use of the entomopathogenic fungus Metarhizium anisopliae against agricultural pests. Very little information has been documented about the diversity and the impact of mycoviruses on M. anisopliae compared to M. robertsii and M. brunneum. This study reports the discovery of mycoviruses associated with native Brazilian Metarhizium spp. strains from the entomopathogen collection of the University of São Paulo, including strains used for mass-production of aerial conidia in sugar-alcohol factories to meet their own demand for controlling sugarcane spittlebugs and used in commercial mycoinsecticides. We also investigated the potential effects of viral infection on the biological traits of some of these strains. Viral-like double-stranded RNA (dsRNA) was found in 61% of the 36 Metarhizium spp. strains analyzed and showed a large variation of different electrophoretic banding patterns consisting of 2 to 8 dsRNA bands in polyacrylamide gels (PAGE). No dsRNA was detected in any of the strains from commercial products used in this study. Efforts to “cure” strains with dsRNA revealed that the inhibitor of protein synthesis cycloheximide was not efficient in eradicating dsRNA viruses from Metarhizium spp. strains. Some dsRNA segments of M. anisopliae ESALQ 26 were lost following hyphal tip subculturing. The dsRNA-variants of M. anisopliae strains ESALQ 866, ESALQ 1256 and ESALQ 1595 were healed after either monoconidial or hyphal tip subculturing. Single spore cultures of M. anisopliae ESALQ 1256 exhibited significant differences in vegetative growth, conidia production, and virulence against Tenebrio molitor larvae, although these differences were not linked with dsRNA. Moreover, fungal variants free of or positive for dsRNA had similar heat and UV tolerance responses. Our results suggest that viral-like dsRNA are very common among Brazilian M. anisopliae strains, but there is sparse evidence that these mycoviruses are harmful to fungal biological traits.

Acaricidal activity of Metarhizium anisopliae isolated from paddocks in the Mexican tropics against two populations of the cattle tick Rhipicephalus microplus.

The acaricidal effects of 55 strains of Metarhizium anisopliae (Metschnikoff) Sorokin, 1883 (Hypocreales: Clavicipitaceae) isolated from paddocks of cattle farms were evaluated in two Rhipicephalus microplus (Canestrini 1887) (Ixodida: Ixodidae) populations, of which one was multi-resistant and one was susceptible to chemical acaricides. Percentage mortality and reproductive efficiency indices in R. microplus were evaluated by adult immersion tests at a dose of 1 × 108 conidia/mL for each fungal strain. Some strains were selected to calculate lethal concentrations to kill 50% (LC50 ) and 99% (LC99 ) of engorged ticks. Strains MaV22, MaV26 and MaV55 induced 100% mortality in R. microplus on day 14. Strains MaV05, MaV09 and MaV22 caused mortality of >90% from day 12 onward in both tick populations. The most effective acaricidal fungal strain, MaV55, inhibited egg laying by 54.86 and 55.86% in acaricide-resistant and -susceptible R. microplus populations, respectively. None of the fungal strains had statistically significant effects on larval hatching. In conclusion, nine strains of M. anisopliae demonstrated high acaricidal effects against R. microplus and reduced its egg laying. No differences in acaricidal effects were observed between the two populations of ticks tested.

Frozen section and electron microscopy studies of the infection of the red palm weevil, Rhynchophorus ferrugineus (coleoptera:curculionidae) by the entomopathogenic fungus Metarhizium anisopliae.

This study determined the pathogenicity of Metarhizium anisopliae strain SD-3 against invasive red palm weevil (RPW), Rhynchophorus ferrugineus Olivier (coleoptera:curculionidae) larvae in Hainan Province, China. Inoculation of 1 × 108 conidia/mL caused 100 % mortality of R. ferrugineus, indicating that the conidia of strain SD-3 were highly virulent. The process of invasion mechanism was showed by scanning electron microscopy (SEM) and frozen section as follows. Once R. ferrugineus was infected by strain SD-3, M. anisopliae hyphae first invaded the cuticular and body cavity of R. ferrugineus. Secondly, well-developed muscles, fat, tracheaes and digestive tube tissues in the abdomen of R. ferrugineus were then decomposed and absorbed by M. anisopliae hyphae, leading to the total destruction of the larvae. Finally, M. anisopliae hyphae reproduced, resulting in a large number of conidia in the body of RPW. The SEM and frozen section are convenient tools to observe the mode of action of entomopathogenic fungi and to observe how M. anisopliae is able to colonize and infect the host.

Different Effects of Metarhizium anisopliae Strains IMI330189 and IBC200614 on Enzymes Activities and Hemocytes of Locusta migratoria L.

BackgroundMetarhizium is an important class of entomopathogenic fungi in the biocontrol of insects, but its virulence is affected by insect immunity. To clarify the mechanism in virulence of Metarhizium, we compared the immunological differences in Locusta migratoria L. when exposed to two strains of Metarhizium anisopliae (Ma).ResultsThe virulence of Ma IMI330189 was significantly higher than that of Ma IBC200614 to locust, and IMI330189 overcame the hemocytes and began destroying the hemocytes of locust at 72 h after spray, while locust is immune to IBC200614. IMI330189 could overcome the humoral immunity of locust by inhibiting the activities of phenol oxidase (PO), esterases, multi-function oxidases (MFOs) and acetylcholinesterases in locust while increasing the activities of glutathione-S-transferases (GSTs), catalase and aryl-acylamidase (AA). However IBC200614 inhibit the activities of GSTs and AA in locust and increase the activities of MFOs, PO, superoxide dismutase, peroxidase and chitinase in locust. The changes of enzymes activities in period of infection showed that the time period between the 2nd and the 5th day after spray is critical in the pathogenic process.ConclusionThese results found the phenomenon that Ma initiatively broke host hemocytes, revealed the correlation between the virulence of Ma and the changes of enzymes activities in host induced by Ma, and clarified the critical period in the infection of Ma. So, these results should provide guidance for the construction of efficient biocontrol Ma strains.

Differential susceptibility of Hyalomma excavatum adults and nymphs to the entomopathogens Metarhizium anisopliae ARSEF 4556 and Steinernema carpocapsae

ABSTRACTThis study investigated the virulence of the entomopathogenic fungus, Metarhizium anisopliae strain ARSEF 4556, and the entomopathogenic nematode Steinernema carpocapsae against adult and nymphal stages of the tick Hyalomma anatolicum excavatum. The fungus was tested at three different concentrations, 106, 107, and 108 conidia ml−1. Ticks were exposed to 4000 IJs of S. carpocapsae in 0.5 ml distilled water in Petri dishes lined with 2 layers of moist filter paper. Adult ticks were not susceptible to M. anisopliae, whereas the nymphs were highly susceptible. Nymph mortality was dose dependent with all ticks being killed at the highest dose 96 hours post-inoculation. In contrast, S. carpocapsae was much more effective against engorged adults than unfed adults or nymphs. Tick susceptibility was not influenced by gender. The mean mortalities of the unfed adult males, females, and nymphs were 30% ± 9.2%, 40% ± 7.5%, and 36% ± 4.7%, respectively. Nymphal mortality was 36% and there was a significant difference between nematode treatment and control group (P < 0.05).

Effect of Three Entomopathogenic Fungi on Three Species of Stingless Bees (Hymenoptera: Apidae) Under Laboratory Conditions.

Development of alternative strategies for pest control with reduced effect on beneficial organisms is a priority given the increasing global loss of biodiversity. Biological control with entomopathogenic fungi arises as a viable option to control insect pests. However, few studies have focused on the consequences of using these organisms on pollinators other than the honey bee ( Apis mellifera L.) or bumble bees ( Bombus spp). We evaluated the pathogenicity of commercial formulations of three widely used entomopathogenic fungi, Metarhizium anisopliae (Metschnikoff) Sorokin, Beauveria bassiana Vuillemin, and Isaria fumosorosea (Wize), to three species of stingless bees: Tetragonisca angustula Latreille, Scaptotrigona mexicana Guérin-Meneville, and Melipona beecheii Bennett. Bioassays consisted of exposing groups of bees to the recommended field concentration of each fungus using a microspray tower under laboratory conditions. Susceptibility to fungi varied greatly among species . Isaria fumosorosea (strain Ifu-lu 01) and the two formulations of B. bassiana (Bea-TNK and BotanicGard) caused <30.3% mortality in all bee species. Metarhizium anisopliae (Meta-TNK and strain Ma-lu 01) was highly active against T. angustula (94.2% mortality) and moderately active against M. beecheii (53.0% mortality) and S. mexicana (38.9% mortality). Though our laboratory-derived results suggest a moderate to high impact of these entomopathogenic fungi on stingless bees, further field studies are required to support this finding.

Enhancing purification of chitosanase from Metarhizium anisopliae by expanded bed adsorption chromatography using Doehlert design

Abstract The use of expanded bed adsorption with three different adsorbents Streamline (SP XL, DEAE and PHENYL) to purify the chitosanase from Metarhizium anisopliae strain with and without clarification using Doehlert design for the optimization of the experiments has been investigated. Chitosanases are enzymes that hydrolyze chitosan, a carbohydrate, resulting oligosaccharides that have many biological remarkable activities, such as anti-cancer, anti-HIV and anti-oxidants activities. The superficial velocity was evaluated in five levels, from 40 to 260 cm h−1, while the type of adsorbent, a qualitative variable, was assessed at three levels, saving materials and time according to the Doehlert design. The results showed that it is possible to purify chitosanase from M. anisopliae by expanded bed adsorption. Chitosanase purification factor ranged from 2 to 3.1-fold and yield ranged from 27.7 to 45.3%. The highest enzyme activity in the elution was 0.06 U/mL values which were higher than or close to those reported. The molecular mass of chitosanase was about 45 kDa using SDS-PAGE.

Study results on experimenting bioproduct of M. anisopliae G09/22 local strain against Eclipophleps bogdanovi sergtarb

It is being main aim to reduce the usage of chemical substances for plant protection, in Mongolian agricultural sector, by isolating and of course determining local strain that can fit in condition of our country specifically to control harmful pests that are having negative impact on the environment especially in the forest and pasture plants. Thus, research work concentrated on isolating bioproduct based on local strain of entomopathogenic fungi Metarhizium anisopliae and to determine its biological activity. Bioproduct of Ma.Mn-G09/22local strain have been experimented with 3 variants with 3 repetitions and comparing it with control in Munh-Khairhan sum of Tuv aimag. Our study involved open field and vivarium experiment which both showing similar results, providing local strain G0922 of Metarhizium anisopliae fungi can be effective against harmful grasshopper Eclipophleps bogdanovi sergtarb under field conditions.Journal of agricultural sciences №15 (02): 147-151, 2015

Characterisation of entomopathogenic fungi used in the biological control programme of Diaphorina citri in Mexico

The production of biological insecticides requires the identification and selection of candidate isolates of entomopathogenic fungi (EPF). The objective of this study was to characterise by virulence factors, single-spore strains of the CHE-CNRCB 303, 305, 307 strains initially identified as Isaria fumosorosea and the 224 strain of Metarhizium anisopliae to identify those with outstanding quality parameters that can serve to improve the control programme for Diaphorina citri (Hemiptera: Liviidae) in Mexico. The size of conidia and phialides was evaluated. The internal transcribed spacers established molecular identity. The selection of single-spore strains was done using radial growth (RG), the production of conidia (PC) and germination (G) rates. Principal component analysis (PCA) was used to determine the correlation between the variables and as screening criterion. Molecular and morphometric analysis confirmed that isolates 303, 305 and 307, and their single-spore strains correspond to the Isaria javanica species. The 224 strain and its single-spore strain were identified as M. anisopliae sensu lato. The statistical analysis of the RG, PC and G variables showed significant differences (P ≤ 0.05) between single-spore strains and their multi-spore strains. PCA showed a correlation between the RG and PC. The assay with Pr1 proteases associated with the surface of the conidia showed significant differences (P ≤ 0.05) for single-spore strains of I. javanica 303/2, 305/1 and 305/5 compared to the original strains. The characterisation of genetically homogeneous populations of EPF will allow us to obtain improved isolates, which are needed for the mass production of mycoinsecticides.