Evaluation Of Entomopathogenic Fungi Research Articles

The Eucalyptus snout beetle in Colombia: Selection and evaluation of entomopathogenic fungi as bioinsecticides against Gonipterus platensis

The Eucalyptus snout beetles, which belong to the Gonipterus scutellatus species complex, cause heavy damage to Eucalyptus spp. worldwide. The species was reported in Antioquia, Colombia for the first time in 2016, threatening more than 115,000 ha of planted Eucalyptus spp. Elsewhere, its damage has been controlled using Anaphes spp. as classical biological control, but Anaphes spp. are not available in Colombia, where there are no documented control methods for this species to date. We identified the Gonipterus species using molecular methods and isolated entomopathogenic fungi from naturally infected beetles collected from the current distribution area in Colombia. We characterised the fungal isolates, selecting the best to develop a biological control agent. We considered insecticidal activity, UV-B radiation tolerance, yield, germination, and enzyme activity of conidia in making our selection. We confirmed the presence of G. platensis in Colombia, with adults naturally infected by Beauveria spp. and Metarhizium spp. From the isolated native fungi, M. brunneum (CA-3), M. robertsii (RI-1), B. bassiana (CA-1) and (CA-2), B. pseudobassiana (SP-1) were identified. We found remarkable differences in response to different variables between the selected isolates and SP-1 and CA-3 were the most virulent. The SP-1 isolate stood out from the rest for being the most tolerant to UV-B radiation, alkaline media, and low temperatures, germinating faster and producing elevated levels of lipases, chitinases, and proteases. The identified promising native fungus isolate, naturally occurring on field individuals, could be used to develop a biopesticide for controlling G. platensis in Eucalyptus spp. plantations in Colombia.

Evaluation of Entomopathogenic Fungi against Peregrinus Maidis (Ashmead)

The present study to evaluate entomopathogenic fungi for the management of sorghum shoot bug, Peregrinus maidis (Ashmead) revealed that, among the entomopathogens applied in various methods (foliar spray and whorl application along with FYM), Raichur strain (UASR BC VL 1) of Lecanicillium lecani (2×108CFU) @ 2g/l directed to whorl region excelled in reducing shoot bug population (5.49/plant), % plant damage (58.62%) and superior plant growth parameters over all other EPF (Entomopathogenic fungi) treatments which was on par results with standard check, cypermethrin 25% EC @ 0.50ml/lit directed to whorl region (5.78/plant & 65.46%). Whereas, all the EPF treatments and untreated control showed superiority in conserving the natural enemy population (spiders and coccinellids) but standard check due to its chemical properties led to the reduction in the beneficial insects with lowest spider (0.54/plant) and coccinellid (0.87/plant) population.

Efficacy of biopesticides against the whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), on parthenocarpic cucumber grown under protected environment in India

BackgroundThe whitefly, Bemisia tabaci (Genn.) (Hemiptera: Aleyrodidae), is one of the most damaging pests of crops grown in open field and under protected conditions. Owing to the indiscriminate use of insecticides, whitefly has developed resistance against various insecticides belonging to different chemical groups. Use of microbial biopesticides (entomopathogenic fungi) can be an effective alternate to chemical insecticides.ResultsThis study was planned for the evaluation of entomopathogenic fungi (EPF) formulations, namely, Beauveria bassiana Balsamo (Vuillemin), Lecanicillium lecanii (Zimmerman) Viegas and Metarhizium anisopliae (Metschnikoff) Sorokin and botanical pesticide, Neem Baan, for the management of different life stages of B. tabaci on parthenocarpic cucumber grown under protected conditions. The liquid formulations of Neem Baan at 10 and 15 ml/l were the most effective (90.7 to 93.3% in eggs, 93.3 to 97.1% in nymphs, and 92.4 to 94.2% reduction in whitefly adults after 3rd spray, respectively) as compared to EPF. Among the EPF, L. lecanii and B. bassiana at 10 and 15 ml/l (80.6 to 86.5% in eggs, 85.7 to 91.5% in nymphs, and 58.5 to 69.2% in whitefly adults after 3rd spray, respectively) were found to be more effective than M. anisopliae at 10 and 15 ml/l (78.4 to 82.8% in eggs, 82.5 to 85.9% in nymphs, and 57.7 to 62.8% in whitefly adults after third spray, respectively) in reducing different life stages of B. tabaci on cucumber. Significantly high yield of cucumber fruits was obtained from the plot where Neem Baan at 10 and 15 ml/l (2337.5 to 2420.8 g/plant) was used. Minimum fruit yield were recorded in untreated control plots.ConclusionsThe integration of these biopesticides in the management schedule of the whitefly under protected conditions will enhance the quality and market value of parthenocarpic cucumbers.

Isolation and evaluation of entomopathogenic fungi against the neotropical brown stink bug Euschistus heros (F.) (Hemiptera: Pentatomidae) under laboratory conditions

ABSTRACT Although the brown stink bug, Euschistus heros (F.) is susceptible to entomopathogenic fungi, only a single formulation is currently available on the Brazilian market for its control. The objective of this work was to isolate entomopathogenic fungi with potential to control E. heros, evaluate their virulence, and determine effective conidial concentrations. Thirty six different fungal isolates were obtained from soil samples and diseased insects and pure cultures of each were established on potato-dextrose agar. Suspensions of 1 × 108 conidia mL−1 were prepared from each isolate and a 5 μL aliquot was inoculated on the dorsum of adult stink bugs (n = 8 replications of 5 bugs each). Three isolates caused 100% mortality of bugs over a 15-day observation period. These were identified by molecular techniques as belonging to the Beauveria bassiana species complex and designated UFSM-1, UFSM-2 and UFSM-26. Further bioassays determined the LC50, LC90 and cumulative mortality functions caused by these three isolates. Isolates UFSM-1 and UFSM-2 stood out as highly virulence, with an LC90 of 5 × 109 conidia mL−1 in 9 days, compared to an LC90 of 8 × 1010 conidia mL−1 for strain UFSM-26. Application of 1 × 108 conidia mL−1 of UFSM-1 and UFSM-2 isolates killed 70% of stink bugs in nine days, whereas the same concentration of UFSM-26 killed only 12%. We conclude that isolates UFSM-1 and UFSM-2 warrant field tests as novel agents for biological control of E. heros.

Evaluation of entomopathogenic fungi against sucking pests of Bhut Jalakia

Experiment was conducted to evaluate the efficacy of six different strains of entomopathogenic fungi and one insecticide molecule against sucking pests of Bhut Jalakia during 2014-15 to 2016-17. Bhut Jalakia is one of the hottest chillis in the world, grown extensively in Assam, Nagaland and Manipur. Aphis gossypii Glover, Scirtothrips dorsalis Hood and Bemisia tabaci (Genn.) are the major sucking pests of Bhut Jalakia inflicting damage right from planting to fruiting stages of the crop. Three rounds of biopesticides @ 1 × 10 8 spores/gm and insecticide (imidacloprid 17.8 SL @ 20 gm a.i./ha) imposed at 3 weeks interval against the pests revealed that imidacloprid 17.8 SL could significantly reduce the mean population of A. gossypii (4.64); S. dorsalis (2.03) and B. tabaci (0.28), closely followed by Beauveria bassiana (NBAIR-Bb-5a) with 7.20, 3.07 and 0.64 per 10 leaves and both the treatments were on par in their efficacy after third spray. The rest of the entomopathogenic fungi were more or less effective in reducing the sucking pests and statistically at par with each other compared to untreated control plot. Highest yield of 52.64 q/ha recorded in imidacloprid treated plot followed by NBAIR strain of Bb-5a with 45.85 q/ha and had no any significant difference from each other. Minimum yield of 26.78 q/ha was obtained in untreated control plot.

Evaluation of Entomopathogenic Fungi against Coffee Antestia Bug, (Antestiopsis Intricate) Under Laboratory Condition at Jimma

Evaluation of Entomopathogenic Fungi against Coffee Antestia Bug, (Antestiopsis Intricate) Under Laboratory Condition at Jimma

Evaluation of Entomopathogenic Fungi and Delivery Methods for Management of Thrips in Chillies

ABSTRACTSuccessful use of entomopathogenic fungi as microbial control agents of thrips depends on strain virulence, an appropriate delivery system, and timing of application. Use of fungal entomopathogens can be an alternative to synthetic insecticides and could play an important role in bio-intensive pest management. Entomopathogenic fungi may be able to be used for management of chilli thrips, Scirtothrips dorsalis Hood. Laboratory bioassays were performed to evaluate fungal isolates of Beauveria, Metarhizium, Lecanicillium against chilli thrips using different delivery systems. The LC50 values against S. dorsalis indicated that the Beauveria bassiana isolate, Bb 112, had the highest virulence with the lowest LC50 values of 0.6 × 106 spores·mL−1. The time mortality response of S. dorsalis to fungal pathogens indicated that isolate Bb 112 had the lowest LT50 value, 97.68 h. In pot culture on chilli (Capsicum frutescens L., cv. K2), among the entomopathogenic fungal isolates (Bb 111, Bb 112, Bb 101, B2, Bb NBAIR, Bb SBI, and Ml flavoviride var. minus), application of Bb 112 at 108 spores·mL−1 had the highest cumulative mean thrips population reduction, 59.73% and 53.88% in both pot culture experiments. The controlled droplet applicator (CDA) delivery system was effective for application of Bb 112 at 108 spores·mL−1 against S. dorsalis. Mycoinsecticides applied with the CDA sprayer can be used in management of low to moderate populations (two to three thrips per leaf) of S. dorsalis.

Evaluation of entomopathogenic fungi against the mealy bug on custard apple

Different entophathogenic fungi were evaluated in field trials at the instructional farm of Krishi Vigyan Kendra (KVK) Dhule provided by Department of Entomology, College of Agriculture, Dhule for the management of mealy bug on custard apple in Kharif season of 2014-15.All the treatments were observed to be effective in reducing mealy bug infestation on custard apple. Among the evaluated insecticide and biopesticides the treatment with Verticillium lecanii 7.5 g/lit. was recorded significantly lowest mealy bug population and was was at par with Verticillium lecanii 5 g/lit. (12.74). The next best treatments protection included Trizophos 40 EC 3 ml/lit. (14.26) and it was at par with Verticillium lecanii 2.5 g/lit. (14.40). The next treatments in this respect were Metarhizium anisopliae 7.5 g/lit. (15.68), Metarhizium anisopliae 5 g/lit. (16.33), Beauveria bassiana 7.5 g/lit. (17.37), Metarhizium anisopliae 2.5 g/lit. (18.13), Beauveria bassiana 5 g/lit. (20.54) and Beauveria bassiana 2.5 g/lit. (22.25). There was an increase in mealy bug population in untreated check to the extent of 35.52 numbers of colonies as compared to treated plots. How to view point the article : Dixit, S.S., Kabre, G.B. and Patil, V.V. (2016). Evaluation of entomopathogenic fungi against the mealy bug on custard apple. Internat. J. Plant Protec., 9(2) : 510-513, DOI : 10.15740/HAS/IJPP/9.2/510-513.

Bioefficacy of mycopathogensVerticillium lecanii Zimmermen andMetarhizium anisopliae Metchnikoff against sucking pests of Bt cotton

Entomopathogenic fungi Verticillium lecanii Zimmermen and Metarhizium anisopliae Metchnikoff have generated a great deal of interest in recent years because of their potential as bio-control component in integrated pest management of cotton. These two mycopathogens were evaluated against sucking pests of Bt cotton during Kharif 2011 and 2012 at Cotton Improvement Project, Mahatma Phule Krishi Vidyapeeth, Rahuri to find out the scope and potentiality of V.lecanii and M.anisopliae against sucking pests of Bt cotton in intra hirsutum Bt hybrid (RCH-2Bt). Mycopathogens V.lecanii (2 x 10 8 cfu/gm and 2 x 10 12 cfu/g) and M.anisopliae @ 2000 g/hectare were evaluated alone and in combination ( V.lecanii + M.anisopliae ). The observations were recorded on 3,5 and 10 days interval after each spray application. Pooled analysis of two years data revealed that V.lecanii (2 x 10 12 cfu/g) @ 2000 g/hectare + M.anisopliae (2 x 10 12 cfu/g) @ 2000 g/ha in combination was found more effective and significantly superior to its lower dose V.lecanii (2 x 10 8 cfu/g)@ 2000 g/ha + M.anisopliae (2 x 10 8 cfu/g) @2000 g/ha. It wasproved superior over all other treatments in reducing aphids, jassids, thrips and whitefly population, however, it was at par with V.lecanii (2 x 10 12 cfu/g) @ 2000 g/ha. Thus, V.lecanii (2 x 10 12 cfu/g) @ 2000 g/ha was found to be the effective dose against all major sucking pests of cotton. Investigation on evaluation of entomopathogenic fungi against natural enemies of sucking pests in Bt cotton revealed that there was no significant adverse impact of V. lecanii and M. anisopliae on the activity of natural enemies viz ., Chrysoperla and Coccinellids; when compared with the population of natural enemies in control. Sole and combine application of V. lecanii and M.anisopliae at all the evaluated doses were not found toxic to natural enemies.

Screening and evaluation of entomopathogenic fungi against the green peach aphid, Myzus persicae, using multiple tools

The green peach aphid, Myzus persicae Sulzer, is an important pest that infests more than 40 families of plant and has become a serious problem due to its high resistance to insecticides. To address this problem, interest in entomopathogenic fungi as biocontrol agents in the context of integrated pest management strategies has increased. In this study, we report the efficient screening of entomopathogenic fungi for control of the green peach aphid through the evaluation of environmental factors as well as virulence. Initial screening based on pathogenicity against the green peach aphid was performed using 342 isolates of entomopathogenic fungi from Korea. Twenty different entomopathogenic fungi were isolated from green peach aphid cadavers supporting fungal conidiation. These isolates were identified by microscopic examination, genetic sequencing of the ITS region, and universally primed PCR (UP-PCR) as follows: 3 isolates of Lecanicillium attenuatum, 9 isolates of Beauveria bassiana, 1 isolate of Metarhizium anisopliae, 1 isolate of Metarhizium flavoviride, 5 isolates of Purpureocillium lilacinum, and 1 isolate of Aspergillus sp. Further virulence and environmental factors such as thermotolerance, UV-B tolerance, and cold activity were evaluated simultaneously to select 20 isolates because the importance of environmental factors in the development of bioinsecticides is greatly increasing. Virulence and environmental factor activities varied based on the fungal isolate. Purpureocillium lilacinum SD17 was selected as the most likely candidate for a biocontrol agent against the green peach aphid based on a relative comparison of its activities, including virulence.

Evaluation of Entomopathogenic Fungi against Potato Tuber Moth (Phthorimaea operculella ZELLER.) in West Shoa, Ethiopia

Potato Tuber Moth, Phthorimaea operculella is a major insect pest of potato (Solanum tuberosum) which has been identified to cause damage both under field and seed storage in Ethiopia. It is a major threat to potato production. A field experiment was carried out at Guder, Toke Kutaye districts to evaluate the effectiveness of different Entomopathogenic fungi and their concentration for the management of potato tuber moth (PTM). Treatment consisted of three species; Beauveria bassiana (PPRC-56), Metarrhizium anisopliae (MM), and Verticilium lecani at three level of concentrations (1x106, 1x107, and 1x108 spore/ml) with Diazinon 60% EC as a standard check and an untreated control. The treatments were laid out in a simple randomize complete block design (RCBD) with three replications. Results showed that B. bassiana significantly reduced the infestation of PTM larvae both on the leaves and tubers followed by the M. anisopliae when compared to V. lecani. Increasing the concentration levels of fungus also showed a significant reduction in the number of larvae and the damage caused on potato leaves. Based on the study findings, B. bassiana and M. anisopliae could be considered for the effective management of PTM in potato in the study area using higher fungal concentrations.

Evaluation of entomopathogenic fungi against the sycamore lace bug, Corythucha ciliata (Say) (Hemiptera: Tingidae)

The sycamore lace bug, Corythucha ciliata (Say) (Hemiptera: Tingidae), is one of the most destructive pests of plane trees (Platanus spp.) worldwide. This pest is a major nuisance in Europe since plane trees are very popular in parks. Thirteen entomopathogenic fungal strains including 4 isolates of Beauveria bassiana, 2 isolates of Beauveria pseudobassiana, 6 isolates of Metarhizium anisopliae, and 1 isolate of Isaria fumosorosea were screened against adults and nymphs of C. ciliata under controlled laboratory conditions in order to test their efficacy and search for an effective and safe biocontrol agent strategy. Each isolate was applied with a conidial concentration of 1 × 107 conidia mL-1 to adults and nymphs of the pest. B. bassiana isolate KTU - 24 showed the highest mortality for both adults and nymphs with 86% within 2 weeks after inoculation. This isolate also caused the highest mycosis for adults and nymphs with 83% and 80%, respectively. Mortalities of the other fungal isolates ranged from 43% to 86% and from 36% to 73% for adults and nymphs. Therefore, B. bassiana KTU - 24 was selected for further dose mortality tests based on its high virulence and mycosis value. Dose-response mortality bioassays using 5 different concentrations (1 × 104, 1 × 105, 1 × 106, 1 × 107, and 1 × 108 conidia mL-1) were performed to determine the lethal concentration (LC50) of this isolate. Based on probit analysis, the LC50 values of isolate B. bassiana KTU - 24 were calculated as 5.51 × 105 and 3.96 × 105 conidia mL-1 against adults and nymphs, respectively. Consequently, B. bassiana KTU - 24 appears to be a promising candidate for further investigations as a biocontrol agent against C. ciliata.

Evaluation of entomopathogenic fungi and a nematode against the soil‐dwelling stages of the crane fly Tipula paludosa

Larvae of the crane fly Tipula paludosa (Diptera: Nematocera) are economically important pests of grasslands, nurseries and organically grown crops. This study was conducted to evaluate several entomopathogenic fungal strains, the entomopathogenic nematode Heterorhabditis bacteriophora and the organophosphate insecticide Dursban WG (75% chlorpyrifos) against larval stages of T. paludosa under laboratory and greenhouse conditions. Metarhizium robertsii strain V1005 was the most virulent, causing 100% larval mortality 4 weeks post-inoculation. Eight other M. robertsii strains and M. brunneum (ARSEF 3297) caused mortality ranging between 0 and 60%, whereas strains of Beauveria bassiana, Isaria fumosorosea and Lecanicillium longisporum were non-pathogenic to T. paludosa. In greenhouse tests, medium (2 × 10(14) conidia ha(-1) ) and high (2 × 10(16) conidia ha(-1) ) concentrations of V1005 gave higher larval mortalities (90 and 100%) than lower (2 × 10(13) conidia ha(-1) ) concentrations (52 and 78%) at 4 and 8 weeks after treatment respectively. Dursban WG gave 100% larval mortality 4 weeks after treatment; H. bacteriophora UWS1 caused 28 and 65% mortality 4 and 8 weeks after treatment respectively. This study shows that M. robertsii V1005 has considerable potential for the control of T. paludosa, thereby reducing the use of chemical insecticides.

Evaluation of entomopathogenic fungi as potential biological control agents of the dengue mosquito, Aedes aegypti (Diptera: Culicidae)

Dengue is a global health concern. Growing insecticide resistance in the primary mosquito vector, Aedes aegypti, limits the effectiveness of vector control, so alternative tools are urgently needed. One approach is the use of biopesticides comprising entomopathogenic fungi, e.g., Beauveria bassiana and Metarhizium anisopliae. These fungi may decrease disease transmission by reducing mosquito vector longevity and also occur worldwide, although many isolates have not been tested for virulence against mosquitoes. Ninety-three isolates of entomopathogenic fungi representing six species (B. bassiana, M. anisopliae, Isaria fumosorosea, I. farinosa, I. flavovirescens, and Lecanicillium spp.) were screened as potential biological control agents of Aedes aegypti. A hierarchical, multi-criteria experimental design was undertaken to find suitable isolates. Initial screening was performed via in vitro assays measuring radial growth and spore persistence, eliminating isolates with poor growth or viability on nutrient-rich substrate. Subsequent measurements of spore persistence revealed that only nine of 30 strains tested had half-lives exceeding 3 weeks. Ten isolates were chosen for in vivo bioassays against adult Ae. aegypti. From these assays, two Australian isolates of B. bassiana, FI-277 and FI-278, appeared to be most promising. Both isolates were shown to be virulent against Ae. aegypti at 20, 26, and 32°C. Spreading spores manually onto substrate was found to be more efficacious than spraying. Ae. aegypti infected by manually-spread spores on cotton substrate were found to have an LT50 of 3.7±0.3 days. These characteristics suggest that FI-277 has promise as a dengue mosquito biocontrol agent, either alone or combined with conventional chemical insecticides.

Laboratory evaluation of entomopathogenic fungi against the white grubs, Holotrichia oblita and Anomala corpulenta (Coleoptera: Scarabaeidae) from the field of peanut, Arachis hypogaea

We evaluated the pathogenicity of nine isolates of entomopathogenic fungi, including six isolates of Metarhizium anisopliae, one of Beauveria bassiana, and two of Beauveria brongniartii, against eggs and various larval instars of two scarab-beetle species, Holotrichia oblita and Anomala corpulenta, under laboratory conditions. The fungal isolates differed in pathogenicity. Generally, the isolates were more pathogenic to A. corpulenta than to H. oblita. Some of the isolates prevented egg hatching and caused larval death. Isolates M2-2 and Br5-8 caused 39 and 27% egg mortality, respectively, and produced 23 and 24% viewable fungal-infection rates in H. oblita. Three isolates had no significant effect on egg hatchability. Three isolates (Br5-8, Br232818, and M200614) caused about 40% mortality in H. oblita first instars. In A. corpulenta, all isolates except M200614 caused more than 60% egg mortality, and M2-2, Br232818 and Br5-8 caused egg-infection rates greater than 50%. M2-2 caused 47% infection and 100% mortality in first-instar larvae of A. corpulenta, while Br5-8 and Br232818 yielded over 80% mortality of the larvae. The three most virulent isolates, M2-2, Br232818 and Br5-8, were selected for further bioassays against second- and third-instar larvae. In addition, seven graduated concentrations of a Br5-8 conidial suspension were assayed against H. oblita second instars. Larval mortality was positively correlated with fungal dosage, and the LC50 was 4.49×106 conidia/mL. These three virulent isolates may be used to prevent H. oblita and A. corpulenta larval infestations in field crops.

Ovicidal and Larvicidal Activity of Conidia and Blastospores of Paecilomyces fumosoroseus (Deuteromycotina: Hyphomycetes) Against Bemisia argentifolii (Homoptera: Aleyrodidae) with a Description of a Bioassay System Allowing Prolonged Survival of Control Insects

Fungi are the only effective entomopathogens of members of the Aleyrodidae and other homopterans because of the piercing and sucking feeding strategy of these insects. The laboratory assessment of the entomopathogenic activity of fungi often requires a prolonged period of observation. Leaf quality can be the limiting factor in bioassays of fungi against whiteflies that require longer observation periods or those that require conditions that are as close to natural ones as possible. A bioassay system is described that utilizes rooted cabbage leaves infested with the highly polyphagous whitefly, Bemisia argentifolii . Using this method, discriminating dosages of aerial conidia and blastospores of two isolates of Paecilomyces fumosoroseus (Pfr) were bioassayed against eggs and nymphs of B. argentifolii . Low, but significant, mortality (10-20%) of eggs was observed 14 days after exposure to 3.8 104 blastospores/cm2 for the Pfr 97 and European Biological Control Laboratory (EBCL) Pfr 42 isolates. Additionally, the majority of crawlers that had hatched from treated eggs died on the surface of the leaves. Exposure of early second-instar nymphs of B. argentifolii to 3.8 103 conidia or blastospores/cm2 of Pfr 97 resulted in mortalities of 27 and 77% respectively. Identical dosages of conidia and blastospores of the Pfr 42 isolate resulted in mortalities of 59 and 68% respectively. The bioassay method described enables the comparative evaluation of entomopathogenic fungi against whiteflies under diverse biotic and abiotic conditions.