Pathogenicity of Metarhizium anisopliae (Metch) Sorok and Beauveria bassiana (Bals) Vuill to adult Phlebotomus duboscqi (Neveu-Lemaire) in the laboratory

Background & objectives: Biological control of sandflies using entomopathogenic fungi is a possible alternativeto the expensive synthetic chemical control. It is potentially sustainable, less hazardous, and relatively inexpensiveand merits further investigations. The objective of this study was to identify the most pathogenic fungal isolate(s)to sandflies in the laboratory.Methods: Isolates of entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana were screenedfor their pathogenicity against Phlebotomus duboscqi. Adult flies were contaminated using the technique describedby Migiro et al (2010). Briefly, flies were exposed to 0.1 g of dry conidia evenly spread on a cotton velvet clothcovering the inner side of a cylindrical plastic tube (95 mm long × 48 mm diam). In all 25 sandflies weretransferred into the cylindrical tube and allowed to walk on the velvet for one minute, after which they weretransferred from the velvet into the cages in Perplex. Insects in the control treatments were exposed to fungusfree velvet cloth before being transferred into similar cages. The treatments were maintained at 25 ± 2°C,60–70% RH and 12L: 12D photoperiod. The experiment was replicated 5 times. The most pathogenic isolateswere selected for further studies.Results: A total of 19 isolates were screened against adult sandflies in the laboratory. Mortality in the controlswas approximately 16.8 ± 1.7 %. All the isolates were found to be pathogenic to P. duboscqi. Mortality rangedbetween 76.8 and 100% on all the fungal isolates tested. The lethal time taken to 50% (LT50) and 90% (LT90(mortality ranged from 3.0–7.8 days and from 5.3–16.2 days, respectively. The virulent isolates, causing mortalitiesof 97.5–100%, were selected for further studies.Interpretation & conclusion: The high susceptibility of sandflies to entomopathogenic fungi suggests that fungiare potential alternatives to chemical control methods. We conclude that application of entomopathogenic fungicould result in acute mortalities of sandflies and reduction of parasite transmission and subsequently, reductionof leishmaniasis risk. This method of biological control has great potential as a new strategy for leishmaniasiscontro

Can fungal biopesticides control malaria?

Recent research has raised the prospect of using insect fungal pathogens for the control of vector-borne diseases such as malaria. In the past, microbial control of insect pests in both medical and agricultural sectors has generally had limited success. We propose that it may now be possible to produce a cheap, safe and green tool for the control of malaria which, in contrast to most chemical insecticides, will not eventually be rendered useless by resistance evolution. Realising this potential will require lateral thinking by biologists, technologists and development agencie

Antibiosis and antixenosis of two cowpea varieties to the legume flower thrips

(African Crop Science Journal, 1998 6(1): 49-60

Managing termites in maize with the entomopathogenic fungus Metarhizium anisopliae

Field experiments were conducted for two seasons to assess the efficacy of the entomopathogenic fungus Metarhizium anisopliae in the control of termites in maize. Application of the fungus at planting was found to significantly reduce maize lodging and increase grain yield in both seasons. However, data from treatment application at tasselling were not consistent. Our results suggest that a granular formulation of M. anisopliae might be a useful option for the management of termites in the maize agroecosystem. RÉSUMÉ Des expérimentations en plein champs ont été conduites durant deux saisons afin d'évaluer l'efficacité du champignon entomopathogène Metarhizium anisopliae pour la lutte contre les termites sur les cultures de maïs. L'application du champignon au moment de la semis s'est révélée très efficace en réduisant la chute des plants de maïs d'une part, et en augmentant le rendement en grains d'autre part, pendant les deux saisons. Cependant, les résultats issus des traitements pendant l'inflorescence des plants de maïs n'étaient pas consistants. Nos résultats suggèrent donc que la formulation du champignon M. anisopliae en granules serait une option appropriée pour le contrôle des termites dans les cultures de maïs

Pathogenicity of entomopathogenic fungi metarhizium anisopliae and beauveria bassiana (Hypocreales: Clavicipitaceae) isolates to the adult pea leafminer (Diptera: Agromyzidae) and prospects of an autoinoculation device for infection in the field

http://dx.doi.org/10.1603/EN0935

ARPN Journal of Agricultural and Biological Science VIRULENCE OF THREE STRAINS OF Beauveria bassiana AGAINST THE BANANA WEEVIL

ABSTRACT The banana weevil, Cosmopolites sordidus Germar, is the most important insect pest of banana and plantain. Beauveria bassiana is the most researched and commercialized fungal biopesticide effective against a variety of insects. Laboratory studies have revealed a great potential of this entomopathogen for use against the banana weevil, Cosmopolites sordidus in banana. Use of traps for collecting adults or infecting them with biopesticides will most likely capture only those weevils in the immediate vicinity of the traps. The indiscriminate use of chemicals has resulted in the development of resistance in insect pests, adverse ecological events, affecting beneficial fauna, and accumulation of residues in the environment. There is considerable need therefore to develop safe and cheaper biocontrol alternatives that can be used to complement existing control methods. The potential of utilizing the entomopathogen B. bassiana for control of banana weevil was evaluated by testing the virulence of three isolates of Beauveria bassiana (ICIPE 273, M353 and M207) at three concentration (10 8 , 3x10 8 and 10 9 ). From previous pathogenicity tests these three isolates were the most pathogenic. At higher fungal concentrations of 3x10 8 and 10 9 adult mortality for all the three isolates was between 35%-70%. The highest mortality was achieved using an elevated concentration of 10 9 , causing mortalities varying from 50-70% 40 days after exposure depending on the isolate. ICIPE 273 was the most virulent, killing 70% of adults followed by M353 (65% mortality) and M207 (51% mortality). This was far much greater than when a standard concentration of 10 8 was used (mortalities ranged between 28%-50%). Differences in virulence among the tested isolates were due to their geographical origins