Muscardine Fungus Research Articles

Effect of adjuvants on growth and spore attributes of <i>Metarhizium anisopliae</i> (Metsch.) Sorokin

The pathogenicity of the fungus, Metarhizium anisopliae, commonly referred to as the green muscardine fungus, has been demonstrated against numerous insect species inhabiting various habitats. Laboratory experiments were carried out to investigate the impact of naturally derived adjuvants on the growth and spore characteristics of M. anisopliae. The natural polysaccharide (guar gum, gum acacia and carboxymethyl cellulose), vegetable oil (groundnut and cottonseed oil) and a synthetic adjuvant were used in the study at three distinct concentrations: 0.05%, 0.1%, and 0.2% v/v or w/v. Among the various adjuvants tested, both gum acacia and guar gum at concentrations of 0.1% and 0.2% were observed to have a positive impact on the growth of the fungus, resulting in enhanced radial mycelial growth, conidiospore production, surface area coverage, and conidiospore germination. Conversely, this fundamental study highlights the detrimental effects of synthetic adjuvants on the growth and spore characteristics of M. anisopliae.

The potential of the entomopathogenic fungus Beauveria bassiana to manage insect pests and diseases

The saprophytic white muscardine fungus Beauveria bassiana (Balsamo) Vuillemin is a potential biocontrol agent against varied insect pests, is a commercially available mycopesticide in many countries, and is extensively used for insect pest management. It produces several metabolites, such as antibacterial, antifungal, cytotoxic, and insecticidal compounds that protect against insect pests and plant pathogens, with dual-purpose crop protection, a new concept in plant disease management. This insect pathogen is also beneficial to plant endophytes that are antagonistic to plant diseases and promote rhizosphere colonizers and plant growth, inducing systemic resistance. The induced systemic responses of fungal endophytes enhance genes that are expressed in pathogenesis and increase the production of pathogenesis-related proteins and defense enzymes. The fungus infects the insects by degrading mechanically and chemically their cuticles. It promotes plant growth, provides systemic protection against pests and pathogens in sustainable agricultural crop production, and reduces the usage of chemical pesticides.

Protein Levels in Metarhizium anisopliae (Metschn.) Sorokīn Infested Tomato Fruit Borer Helicoverpa armigera Hubner (Lepidoptera; Noctuidae)

The tomato fruit borer, Helicoverpa armigera Hubner (Lepidoptera; Noctuidae), is responsible for significant yield losses in tomatoes and employing chemical pesticides leads to unwarranted environmental issues. The use of entomopathogens in tomato Integrated Pest Management reduces the dependency on chemical insecticides. The green muscardine fungus Metarhizium anisopliae is an important entomopathogen used worldwide against many lepidopteran and coleopteran pests. The potential of M. anisopliae depends on its ability to overcome the host defence mechanisms. The immune system in the H. armigera in response to M. anisopliae infection can be revealed using protein analysis. The order of efficacy of four M. anisopliae strains against second and fourth instar H. armigera under laboratory conditions was ICAR SBI VS 8 > ICAR SBI I >ICAR SBI S69 > ICAR SBI MA4. The protein concentration increased with a decrease in M. anisopliae strain concentration in the second and fourth H. armigera larvae. The highly virulent ICAR SBI VS 8 infested H. armigera showed a decline in protein concentration up to 168 h (14.99 mg/g). The second and fourth instar H. armigera, showed similar protein concentration trends in response to M. anisopliae infestation. The virulent ICAR SBI VS 8 strain can resist the host insect's immune response and cause infection to the H. armigera.

Evaluating in vitro Compatibility of Pesticides with Metarhizium anisopliae (Metchnikoff) Sorokin and Its Pathogenicity against Aphis craccivora Koch

An in vitro trial was conducted in the Department of Entomology, Dr. Balasaheb Sawant Konkan Krishi Vidyapeeth, Dapoli, Ratnagiri, Maharashtra; to determine the compatibility of green muscardine fungus, Metarhizium anisopliae (Metachnikoff) Sorokin with pesticides and its pathogenicity against A. craccivora. Azadirachtin, Buprofezin and Sulphur were the most suitable pesticides as it showed significantly superior growth on potato dextrose agar media over untreated control. However, Emamectin benzoate, Azadirachtin, Profenophos, Indoxacarb, Thiophanate, Paraquat Dichloride and Glyphosate showed significantly higher mean mycelial weight over the untreated control on potato broth medium. At the same time, amongst pesticides used in the experiment; only insecticides (Emamectin benzoate, Azadirachtin and Deltamethrin) reported synergistic increase in conidial count with the untreated control, while fungicides and herbicides reported drastic reduction in conidial count. The pathogenicity of M. anisopliae harvested from the pesticide treatments against A. craccivora revealed that all the pesticides investigated had reduced its pathogenicity in comparison to untreated control. However Emamectin benzoate, Indoxacarb and Paraquat dichloride showed maximum per cent mortality and can be used in combination with M. anisopliae.

Molecular characterization of gut bacterias of American cockroach and their interaction with white muscardine fungus

Molecular characterization of gut bacterias of American cockroach and their interaction with white muscardine fungus

Antagonistic potential of Beauveria bassiana (Balsamo) Vuillemin against Pythium myriotylum causing damping off of tomato

Beauveria bassiana (Balsamo) Vuillemin, a white muscardine fungus has widely drawn attention of crop protection practitioners as potential biocontrol agent against insect-pests since decades. In the present study, antagonistic potential of 22 native of B. bassiana isolates were evaluated against damping-off disease of tomato caused by Pythium sp. Results showed that all B. bassiana isolates were able to inhibit mycelial growth of P. myriotylum to the extent of 68–82%. Further studies were conducted to understand the ability of screened B. bassiana isolates to produce cell wall degrading enzymes (CWDEs) viz., amylase, caesinase, chitinase, cellulase, lipase and protease respectively. The potential B. bassiana isolates showed dynamic colonization efficiency in tomato plants with colonization percentage (%) as high as 72–80% through seed inoculation. Eventually, potential isolate BP1.1 has showed wide pH tolerance ability ranging from pH 6–10. Further, potential isolate B. bassiana BP1.1 was evaluated for their efficacy against damping off of tomato under in vitro condition yielding higher germination percentage of 87.34% of and lower disease incidence up to 33.45% under treatment combinations. These findings provide substantial evidences on multifarious potential of B. bassiana as antagonist as well as plant growth promoter in addition to a potential entomopathogen, thus paves the way of a newer domain in the arena of crop protection.

Antifungal ability of Beauveria bassiana (Balsamo) Vuillemin against Curvularia lunata causing leaf spot of rice

Beauveria bassiana (Balsamo) Vuillemin, a white muscardine fungus has widely drawn attention of crop protection practitioners as potential biocontrol agent against insect-pests since decades. In the present study, antagonistic potential of 53 native isolates of B. bassiana were evaluated against Curvularia lunata causing leaf spot as well as seed borne disease of rice. Results showed that all B. bassiana isolates were able to inhibit mycelial growth of C. lunata to the extent of 50-63.33% through varied mechanisms viz., competition and diffusible non-volatile metabolites. However, potential isolates of B. bassiana also exhibited inhibition of mycelial growth of C. lunata to the maximum up to 67.78% through release of volatile inhibitory metabolites. These findings provide substantial evidences on multifarious potential of B. bassiana as plant disease antagonist in addition to a potential entomopathogen, thus paves the way of a newer domain in the arena of crop protection.

Exploration of indigenous strains of the green muscardine fungus from soils and their pathogenicity against the tobacco caterpillar, Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae)

In the recent years, the keen interest has been increased towards biological control-based management practices using entomopathogenic fungi (EPF) for the control of many economically important insects. In this management practices, selection of right strains of EPF is an important criteria to control the target pests in effective manner. In this context, this research work was formulated to find out environmentally effective strains of EPF in the soils of costal districts of Andhra Pradesh. Out of 135 soil samples collected, 8 soil samples yielded 8 strains of Metarhizium anisopliae. Among all 8 M. anisopliae isolates, the least median lethal concentration (LC50) for 2nd instar of the tobacco caterpillar, Spodoptera litura (Lepidoptera: Noctuidae) was 1.24 × 105 spores ml-1 in M-7, followed by 1.72 × 105 spores ml-1 in M-5 and 1.86 × 105 spores ml-1 in M-4 in an increasing order. Likewise, the median lethal time (LT50) values of different isolates of EPF against 2nd instar of S.litura were calculated for a uniform highest dose of 1 × 108 spores ml−1. Among all 8 M. anisopliae isolates, the lowest LT50 was observed as 186.44 hours post infection (hpi) with M-5 and 189.34 hpi with M-7.

Impact of area-wide extension approach for bio-management of rhinoceros beetle with Metarhizium anisopliae

<p>Area-wide community extension approach (AWCA) was pilot tested for bio-management of rhinoceros beetle in Edava panchayat of Thiruvananthapuram district, Kerala state during the period 2010-2013. It focused on holdings having potential breeding sites of the pest and were treated with green muscardine fungus (GMF) <em>Metarhizium anisopliae</em> (Metsch.), multiplied at farm level by trained farm women groups. The project was implemented as participatory action research in an area of 520 ha of coconut involving over 5500 small and marginal farmers and stakeholders. AWCA proved to reduce the variability of technology impact in pest management compared to individual level of adoption. Significant reduction in the percentage incidence of rhinoceros beetles (72.9 ± 9.3 to 58.1 ± 9.3) was achieved in Edava panchayat whereas, it was more or less same (74.5%) during the period 2010-2013 in a non-intervention area (Kottamkara panchayat in Kollam district), where, only conventional extension approach followed. Similarly the average number of symptoms in coconut fronds per palm was also found to be reduced in AWCA area. It ranged from 1.6 to 4.6 before interventions and reduced to a range of 1.0 to 2.8 after interventions. In the non-intervention area it remained almost same (2.9 and 3.0 cuts per palm, respectively in 2010 and 2013). Impact of AWCA was observed to be more or less geographically contiguous on depicting the percentage reduction in severity of rhinoceros infestation in different wards of Edava panchayat using GIS tools.</p>

Pathogenesis of Entomopathogenic Fungus, <I>Metarhizium anisopliae</I> (Metsch.) Sorokin., on Mealybug, <I>Paracoccus marginatus</I> (Williams and Granara De Willink) (Homoptera:Pseudococcidae)

A study was conducted to investigate the basis and mode of infection of the entomopathogenic green muscardine fungus, Metarhizium anisopliae on the mealybug, Paracoccus marginatus . The pathogenesis of M. anisopliae on P. marginatus was studied at 24, 48, 72, 96, 120, 144 and 168 hours after inoculation. The conidial adhesion and germination process of M. anisopliae occurred within 24 hours after inoculation. The hyphae penetrated the epicuticle and reached the endocuticle within 48 to 72 hours after inoculation. Lysis of the endocuticle occurred while the penetrant hyphae invaded into the epidermis. Invasion and colonization of hyphal bodies into the haemocoel of P. marginatus was observed at 72 to 120 hours after inoculation. By 120 to 144 hours after inoculation, there was considerable abundance of hyphae that extensively colonized on the host and complete invasion occurred at 168 hours after inoculation. At this stage, the larvae became moribund and died. Hyphae re-emerged out of the cuticle after 168 hours after inoculation, and grew all over the surface forming a green mycelial mat. The developmental cycle of M. anisopliae on P. marginatus took 172 to 196 hours to disintegrate and kill the insect from the day of inoculation.

Effect of Selected Pesticides on the Growth Parameters of Metarhizium anisopliae (Metch.) Sorokin

In vitro compatibility studies were conducted with the green muscardine fungus, Metarhizium anisopliae (Metch.) Sorokin and commonly used pesticides. The test insecticides viz., spinosad, indoxacarb, novaluron and cartap hydrochloride after 21 days recorded 6.42, 5.86, 5.74 and 5.30 cm radial growth of M. anisopliae , respectively and all these treatments were on par with each other and with that of control. The conidial concentration per cm of M. anisopliae in spinosad amended media was highest and lowest in cartap hydrochloride. The conidial viability of M. anisopliae in spinosad, indoxacarb, novaluron and cartap hydrochloride treated media was 89.2, 84.6, 80.4 and 77.4 per cent, respectively. No significant difference in radial growth of M. anisopliae was found with tebuconazole, azoxystrobin and chlorothalonil, whereas total inhibition of radial growth was observed in propiconazole treated medium. Significant reduction of M. anisopliae conidial concentration per cm was recorded in tebuconazole and azoxystrobin treated media.

Key Mortality Factors of Spodoptera litura (Fabricius) and Trichoplusia ni (Hubner) Infesting Cabbage

Spodoptera litura (Fabricius) passed through one generation each during rainy and winter seasons on cabbage, while Trichoplusia ni (Hubner) completed two generations only during rainy season, at College of Agriculture, Latur. Apanteles sp., green muscardine fungus and an unidentified tachinid fly were the major mortality factors of S. litura and T. ni infesting cabbage during rainy season and Campoletis chlorideae during winter season. In addition to the above, unidentified parasitoids, white muscardine fungus and NPV were also identified as key mortality factors of T. ni .

Bioefficacy of white muscardine fungus, Beauveria bassiana (Balsamo) Vuillemin and entomopathogenic nematode, Heterorhabditis indica (Poinar) against rice blue beetle, Leptispa pygmaea Baly.

Laboratory studies were conducted during the year 2005-2006 to find out the efficacy of the white muscardine fungus, Beauveria bassiana (Balsamo) Vuillemin and the entomopathogenic nematode, Heterorhabditis indica (Poinar) against adult and grubs of rice blue beetle, Leptispa pygmaea Baly. B. bassiana caused a cumulative adult mortality of 56.67-80.00 per cent at 105-109 spores ml -1 and the LC 50 value was 2.26x10 4 spores ml -1 . The entomopathogenic nematode, H. indica caused a cumulative mortality of 66.67-91.67 per cent at concentrations of 5IJs to 9IJs in the grubs of L. pygmaea . The cumulative LC 50 value was 3.83IJs. The mortality of L. pygmaea was found to increase with reducing dose and increasing exposure period of both B. bassiana and H. indica. The effective pathogenicity of B. bassiana and H. indica against L. pygmaea is reported for the first time.

TRI-TROPIC INTERACTION OF COTTON, RED COTTON BUG AND GREEN MUSCARDINE FUNGI UNDER IN-VITRO CONDITION

ABSTRACT Laboratory bioassay was conducted to find out the impact of a green muscardine fungus, Metarhizium anisopliae (Metsch.), Sorokin (Deuteromycotina: Hyphomycetes) on an economically important cotton pest, red cotton bug Dysdercus cingulatus (Fab.) (Hemiptera: Pyrrhocoridae) under laboratory condition using cotton saplings, Gossypium hirsutum Linn. (Malvaceae). Two fungal isolates of M. anisopliae (CPRC 16 and CPRC 18) and also a standard M. anisopliae MTCC 892 were used for the present study. The present experimental results revealed that the tested strains were effective against the red cotton bug on the cotton saplings. Highest mortality (86.67 %) was observed in CPRC 18 at 1.9 x 108 spores/ml, followed by CPRC 16 (80.64 %) at 2.8 x 108 spores/ml. Subsequently, the LC50 values were also lower (2.27 x 105) and higher 2.83 x 106) for CPRC 18 and CPRC 16 respectively. Percentage of insect infected with M. anisopliae of the former category was highest among live and dead cadavers at 80.00 and 92.30 respectively. The infected dead cadavers were attached on the upper surface of the cotton leaves, which grew very healthy. In future M. anisopliae CPRC 18 can be used to manage this sucking pest in cotton field

Preliminary Study on Entomopathogens for White Grub Management in Nepal

White grubs are increasingly important pests of cereal and cash crops in Nepal. The situation is further aggravated for their management due to their high level resistance to insecticides, as an alternative method of management. To overcome this problem, an insect pathogenic fungal- based antagonists are coming out. Series of activities were conducted since the mid of 2002 at Tribhuvan University, Institute of Agriculture and Animal Sciences (IAAS), Rampur and in farmers' fields in Nepal. Several dozens of isolates of the insect pathogenic fungi, Metarhizium anisopliae (green muscardine fungus) and more than half a dozen of Beauveria bassiana (white muscardine fungus) were recovered from infested soil and diseased insects by using a selective medium and the Galleria bait method (GBM). Isolation, maintenance, mass production and efficacy tests of M. anisopliae were conducted under captivity. A three-tier screening strategies; exploration of the indigenous fungal based bioagents, screening of the virulence under captivity and field tests were initiated with M. anisopliae. With the preliminary screening, four isolates namely, M1, M6, M18 and M48 being identified as pathogenic for insect pest larva (Maladera sp.) at concentrations of 105 and 107 spores/ml. Mass production in barley kernels was achieved into autoclavable polybags, however, field tests are under way in different locations of farmers field in Nepal. J. Inst. Agric. Anim. Sci. 25:39-46

Natural Enemies of Micraspis crocea Mulsant (Coleoptera: Coccinellidae)

Field survey and laboratory studies were conducted to gather information on the natural enemies of Micraspis crocea. A number of predators, parasitoids and entomopathogens were observed to be associated with this species of beetle. Among the predators, the spiders were quite common in the field attacking both the larvae and adult beetles. Four species of spiders, Tetragnatha maxillosa Thorell, Argiope catenulata Doelschall, Oxyopes lineatipes C.L. Koch and Lycosa pseudoannulata Bosenberg and Strand were recorded belonging to 4 families: Tetragnathidae, Araneidae, Oxyopidae and Lycosidae, respectively. Among the species, Oxyopes lineatipes had a hight rate of consumption of the beetle larvae in the laboratory. Other insect predators observed included long-horned grasshoppers (Conocephalus longipennis), crickets (Metioche vittacolis Stal), carabid beetles (Ophionea nigrofasciata Schmidt-Goebel) and species of ant (Solenopsis germinata Fabricius). An Encyrtid wasp was also observed to parasitize the larvae of M. crocea while the white muscardine fungus, Beauveria bassiana Balsamo (Vuillemin) was found to infect the adult beetles in the field.

Distribution, Spread and Management Practices Against Rice Black Bug in Leyte

Rice black bug infestation in the island of Leyte was noticed in late 2001 in Libagon, Southern Leyte. Spread of infestation continued irregularly in many municipalities of Leyte in a year. Light trapping, delayed and synchronous rice planting, duck herding, handpicking of rice blag bug, fallowing, weeding and application of Metarhizium anisopliae were some of the control strategies done by farmers in reducing rice black bug population. Natural enemies that were observed to be present in the field were Solenopsis sp. (red ant), Micraspis crocet Mulsant (coccinellid beetle), Ophionia nigrofasciata (Schmidt-Goebel) [ground beeetle], Metioche vittaticollis (cricket), salticid (jumping spider), Tetragnatha sp. (four-jawed spider), Lycosa sp. (ground spider), and Oxyopes sp. (lynx spider), Telenomus sp. (Order Hymenoptera, wasp) and M. anisopliae (green muscardine fungus)

A new record of white muscardine fungus on internode borer of sugarcane

The white muscardine fungus,Beauveria bassiana (Bals.) Vuill., was recorded for the first time on sugarcane internode borer,Chilo sacchariphagus indicus (Kapur) in a field survey conducted at Coimbatore, Tamil Nadu. In laboratory tests, the fungus caused 10.0 to 93.3% mortality in third instar larvae and 3.3 to 100.0% mortality in fourth instar larvae when treated at 104–109 spores/ml. The incubation period varied from 6.2 to 13.0 days in third instar and 5.8 to 10.0 days in fourth instar. The mean spore production/larva varied from 0.04 × 109 to 0.72 × 109 in third instar and 0.11 × 109 to 3.44 × 109 spores/larva in fourth instar.

Pathogenicity of Beauveria Bassiana (Bals.) Vuill, on Developmental Stages of Rice Hispa, Dicladispa Armigera (Olivier)

Phenological studies on the white muscardine fungus Beauveria bassiana (8als.) Vuill, and Dicladispa armigera (Olivier), a serious insect pest of rice in Assam, India (Hazarika and Dutta, 1991), revealed that the fungus was adapted to the rainfed rice ecosystem. The fungus occurred naturally as an effective biocontrol agent suppressing D.armigera populations (Hazarika and Puzari, 1990; Puzari and Hazarika 1991, 1992). Agarwal (1990) showed the association of B.bassiana with egg, larva, pupa and adults of different insects with variable susceptibility to different stages. This investigation depicts such effects on the embryonic and post embryonic stages of D. armigera .

Microbial control of coconut leaf beetle ( Brontispa longissima) with green muscardine fungus, Metarhizium anisopliae var. anisopliae

A domestic strain of Metarhizium anisopliae var. anisopliae (MA-1) was isolated from infected coconut leaf beetles (CLB), Brontispa longissima. Mycelial growth of this green muscardine fungus was better in Sabouraud dextrose broth (SDB) or SDB supplemented with yeast extract than in Campbell's and other media. In both liquid and solid phase, V-8 media effectively promoted sporulation of MA-1. The optimal temperatures and relative humidities for conidia germination were 24°–30°C and 100 – 92.5% RH, respectively. In a pathogenicity test, the mortalities of larvae, pupae, and adults of CLB were 100% when they were inoculated with MA-1 conidia suspension at a density of 2.15 × 10 7 conidia/ml. Even at a density of 2.17 × 10 3 conidia/ml, the mortality of larvae still reached 47% and pupae still reached 60%. Strain MA-1 had a higher virulence on CLB than another isolate of M. anisopliae and Beauveria bassiana. Two field trials of microbial control of CLB were conducted in the Pingtung area (southern part of Taiwan) in 1986 and 1987. CLB could not be detected after three applications of MA-1 formulated as a homogeneous biomass, in granules or in a conidial suspension.