Tolypocladium cylindrosporum (Deuteromycotina: Moniliales), a fungal pathogen of the mosquito Aedes australis

2011

Entomopathogens are significant natural enemies for mosquitoes. We have investigated the adulticidal efficacies of metabolites of Trichophyton ajelloi and Lagenidium giganteum against Culex quinquefasciatus and Aedes aegypti simultaneously. The T. ajelloi was grown on Sabouraud's dextrose broth medium at 25 ± 2°C and relative humidity at 75 ± 5% for 15 days. L. giganteum was grown in peptone yeast extract glucose broth at 25 ± 2°C and relative humidity 75 ± 5% for 15 days. The filtrations of metabolites have been made by using Whatman-1 filter paper then with the flash chromatograph. The bioassays were conducted as per the World Health Organization's methods and protocols (2006). In this significant investigations, the metabolites of T. ajelloi have been found highly susceptible against A. aegypti with LC(99)-7.24 ml after an exposure time of 24 h with a comparison, the LC(99)-66 ml was observed against C. quinquefasciatus after exposure of 24 h. Moreover, the L. giganteum metabolites have shown higher pathogenicity against C. quinquefasciatus with LC(99)-11.3 ml and A. aegypti with LC(99)-15.49 ml. Although, the efficacy in adults could be achieved with higher concentration can be significant also. Their adulticidal activities in different climatic zones are plausible with metabolites which have better LT values of T. ajelloi.

Section: Preparation Of Broth and Culture Of T Ajelloimentioning

confidence: 99%

“…The Sabouraud's dextrose broth was prepared by the method of Garder and Pillai (1987). Four 250-mL conical flasks, each containing 100 mL of Sabouraud's dextrose broth (dextrose, 40 g; peptone, 10 g; deionized water, 1,000 ml) were autoclaved at 20 psi for 20 min.…”

Section: Preparation Of Broth and Culture Of T Ajelloimentioning

confidence: 99%

Efficacy of the Trichophyton ajelloi and Lagenidium giganteum metabolites against mosquitoes after flash chromatography

Singh

2011

“…The Subauraud's dextrose broth (SDB) was prepared by the method of Gardner and Pillai (1987). Five 250 ml conical flask, each containing 100 ml Suboraud dextrose broth (Dextrose 40 g, peptone 10 g, deionized water 1,000 ml) were autoclaved at 20 psi for 20 min.…”

Section: Preparation Of Broth and Culture Of C Keratinophilummentioning

confidence: 99%

Effect of Chrysosporium keratinophilum metabolites against Culex quinquefasciatus after chromatographic purification

Soni

2010

Chrysosporium keratinophilum is known to be a keratinophilic fungus and an effective mosquito control agent. This fungus was grown on Sabauraud dextrose broth in the laboratory at 25°C, while the relative humidity was maintained at 75 ± 5% for 15 days. Filtration process of metabolites was done using whatman-1 filter paper, column chromatography and flash, chromatography. Larvicidal efficacy was performed against all instars of Culex quinquefasciatus. Larvicidal efficacy was performed at six different concentrations with different effective ratios (ethanol/metabolites: 9:1, 8:2, 7:3, 6:4, 5:5, 4:6, 3:7, 2:8, and 1:9). The mortality values were then subjected by the probit analysis. The larval mortalities were observed for a period of 24, 48, and 72 h, respectively. The first and second instars were highly susceptible to 2:8 ratio. In the first instar after column chromatography, LC(50) =26.66 ppm, LC(90) =121.96 ppm, LC(99) =231.86 ppm were observed after 72 h, while after flash chromatography the LC(50) =20 ppm, LC(90) =123.02 ppm, LC(99) =281.83 ppm were observed after 48 h. In the second instar after column chromatography, LC(50) =18.19 ppm, LC(90) =102.32 ppm, LC(99) =162.18 ppm were observed after 72 h, while doing flash chromatography 100% mortality could be recorded after 24 h. In the third instar after column chromatography, the LC(50) =38.01 ppm, LC(90) =131.82 ppm, LC(99) =245.47 ppm were observed after 72 h, while after flash chromatography the LC(50) =17.78 ppm, LC(90) =100 ppm, LC(99) =151.35 ppm. In the fourth instar, LC(50) =61.65 ppm, LC(90) =181.97 ppm, LC(99) =436.51 ppm, while after flash chromatography LC(50) =40 ppm, LC(90) =120 ppm, and LC(99) =223.87 ppm were observed after 72 h. The extracellular metabolites of C. keratinophilum could be a fungal based larvicides resource for the control of C. quinquefasciatus larvae. This could be another agent for biotechnological exploitation, if found suitable in field trials.

“…Pure cultures were prepared by transferring a sub-sample of each fungal colony found on the feathers to separate petri plates containing SDA (Ranbaxy, SAS Nagar, India). Chloramphenicol (50 μg/mL) was added to the SDA as a bacteriostatic agent (Gardner and Pillai 1987). Sabouraud dextrose agar petri plates with more than one fungal colony were recultured as needed to isolate a pure colony.…”

Section: Isolation Of Soil Fungimentioning

confidence: 99%

“…Lacey et al (1988) and Alves et al (2002) evaluated the potential of M. anisopliae isolates against Culex quinquefasciatus Say by altering the methods of inoculation. The deuteromycetes fungi Tolypocladium cylindrosporum Gams and Culicinomyces clavosporus Couch, Romney and Rao have proved to be useful against mosquitoes in temperate countries (Cooper and Sweeney 1982;Gardner and Pillai 1987). Serit and Yap (1984) studied the effect of T. cylindrosporum on the third instar of four mosquito species, including C. quinquefasciatus, and found it to be effective.…”

Section: Introductionmentioning

confidence: 97%

Laboratory and field evaluation of the fungus Chrysosporium lobatum against the larvae of the mosquito Culex quinquefasciatus

Mohanty

2008

Eleven fungal species in three genera were isolated from the soil at Agra, India by the feather-baiting technique. Out of the 11 species, Chrysosporium lobatum Scharapov, a deuteromycetous (Moniliales: Moniliaceae) fungus, caused high mortality of Culex quinquefasciatus Say (Diptera: Culicidae) larvae in the laboratory. Laboratory and field trials were carried out to study the efficacy of C. lobatum against various instars of C. quinquefasciatus. In the laboratory bioassays, first, second and third instar larvae were assessed separately. Conidia of C. lobatum that were 15 days old were used both in laboratory and field bioassays. Six different concentrations were used in the laboratory bioassays (10, 10(3), 10(4), 5x10(4), 10(5) and 10(6) conidia/mL), and one concentration was tested in the field trials (10(6) conidia/mL). The LC50 values with 95% fiducial limits and probit equations were calculated by the probit analysis. Significant (analysis o.f variance (ANOVA): P<0.0001) mortality difference between the instars of C. quinquefasciatus was observed after 72 h of exposure to conidia of C. lobatum. The third instar C. quinquefasciatus were 319- and 25-fold more susceptible to C. lobatum (0.47x10(3) conidia/mL) than the first and second instars, respectively. The cuticle of the abdominal region and anal papillae were densely covered by the C. lobatum conidia. In the field trials, populations had declined significantly (t test, P=0.003) 15 days after inoculation in the four test pools. Significantly (t test, P=0.03) higher mortality was observed in the pools with water quality that was lower in total dissolved solids, hardness, chemical oxygen demand and conductivity. Based on the performance and survival in the trial, C. lobatum may be considered as a bio-control agent of mosquitoes.