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C. Prior - One of the best experts on this subject based on the ideXlab platform.

  • long term storage of Metarhizium Flavoviride conidia in oil formulations for the control of locusts and grasshoppers
    Biocontrol Science and Technology, 1995
    Co-Authors: D. Moore, Roy P Bateman, M Carey, C. Prior
    Abstract:

    Freshly harvested conidia of Metarhizium Flavoviride (Gams & Rozsypal) were stored in two vegetable oils, groundnut or soya, or a mineral oil, Edelex. They were diluted with either Shellsol K or deodorized kerosene, and antioxidants were added to half of the vegetable oil formulations. Dried non-indicating silica gel was added to half of the formulations before storage at 8 or 17 C. Undried conidia, those without silica gel, lost viability rapidly, with germination dropping below 40% after 9 and 32 weeks at 17 and 8 C respectively. After 127 weeks (ca. 30 months) in storage, germination remained at over 60 and 80% for the dried formulations at 17 and 8 C respectively (after an unexplained drop in germination after 16-18 months in storage). Comparable figures for 160 weeks (ca. 37 months) were 47 and 68%. These figures represented germination after 24 h of incubation; after 48 h of incubation, germination was 79 and 89% from samples stored for 160 weeks at 17 and 8 C respectively. Representative formulatio...

  • Initial Field Assessment of Metarhizium Flavoviride Gams and Rozsypal (Deuteromycetina: Hyphomycetes) for Control of Chortoicetes terminifera (Walker) (Orthoptera: Acrididae)
    Australian Journal of Entomology, 1995
    Co-Authors: G. H. S. Hooper, Richard J. Milner, P.a. Spurgin, C. Prior
    Abstract:

    An oil based formulation of an Australian isolate of Metarhizium Flavoviride was applied as an ultra low volume spray against nymphal bands of Chortoicetes terminifera in spring 1993. Up to 41% of sprayed locusts, sampled 1 d after treatment, died from the disease when incubated at 20-28°. Field observations 21 d after spraying showed that the density of the treated nymphal bands was one-third that of the controls.

  • Influence of Moisture Content on Temperature Tolerance and Storage of Metarhizium Flavoviride Conidia in an Oil Formulation
    Biocontrol Science and Technology, 1995
    Co-Authors: S. Hedgecock, D. Moore, P. M. Higgins, C. Prior
    Abstract:

    Investigations of the temperature tolerances of Metarhizium Flavoviride conidia, of different moisture contents, in an oil formulation were carried out. The conidia were dried to 5, 9, 15 or 19% moisture contents and exposed to a range of temperatures, -15, 12, 25, 38, 48 and 55 C. Viability declined due to high temperatures and high moisture contents. After 4 months of storage, the conidia were at over 80% viability in all but the 19% moisture content group of the 25 C treatment and all the samples stored at lower temperatures. In a second experiment, conidia dried to 4-5% moisture content showed greater temperature tolerance than conidia with higher moisture contents. Short-term storage under adverse conditions could be feasible with conidia dried to a suitable degree.

  • control of phaulacridium vittatum sjostedt orthoptera acrididae in field cages using an oil based spray of Metarhizium Flavoviride gams and rozsypal deuteromycetina hyphomycetes
    Australian Journal of Entomology, 1994
    Co-Authors: R J Milner, G. G. Lutton, T. R. Hartley, C. Prior
    Abstract:

    Conidia of an isolate of Metarhizium Flavoviride, F1985 suspended in oil were sprayed onto mainly adult Phaulacridium vittatum (Sjostedt) in field cages at two dose rates: 2 × 109 and 2 × 108 conodia/mL. Both rates were effective in killing all P. vittatum in the cages in 3 weeks, under the prevailing cool conditions. Samples of grasshoppers taken from the treated cages at 4, 8 and 14 d post-spraying died within 1–6 d when placed at constant 26°C in the laboratory. Samples of foliage fed to healthy grasshoppers showed that some infections conidia persisted for 14 d. the results indicate that it may be possible to control P. vittatum with an oil-based spray of conidia of M. Flavoviride.

  • Effects of temperature on the viability of the conidia of Metarhizium Flavoviride in oil formulations
    Mycological Research, 1994
    Co-Authors: G V Mcclatchie, R. P. Bateman, D. Moore, C. Prior
    Abstract:

    The effects of temperature on the survival of conidia of the entomopathogenic Metarhizium Flavoviride in oil formulations for ultra low volume application were investigated. High temperature treatments caused delay in germination as well as death; drying conidia by adding dried silica gel to oil formulations greatly increased temperature tolerance. Conidia were more tolerant to temperature extremes than suggested from previous work with > 80% germination recorded from dried conidia exposed to 60 °C for 90 min and 59% and 20% surviving 8 and 42 d, respectively, at 55°. Under some circumstances reduced germination following high temperature exposure was reversed by a subsequent storage period at lower temperatures. Conidia produced at 30° were more tolerant of high temperature than conidia produced at 26° and increasing the sucrose content of the growth media from 2% to 8% reduced tolerance.

C. J. Lomer - One of the best experts on this subject based on the ideXlab platform.

  • Pratiques Paysannes et Utilisation Potentielle de Metarhizium Flavoviride Gams & Rozsypal en Lutte Anti-Acridienne au Niger
    International Journal of Tropical Insect Science, 1999
    Co-Authors: Idrissa Halidou Maiga, O.-k. Douro-kpindou, C. J. Lomer, J. Langewald
    Abstract:

    A socio-economic study was executed in South East Niger to determine the conditions under which a novel mycopesticide based on the fungus Metarhizium Flavoviride could be introduced for locust and grasshopper control as a possible alternative reducing the use of synthetic chemicals. From the interviews, all farmers estimated locusts and grasshoppers to be one of three major pests. The survey revealed that 93.8% of the farmers conduct collective pesticide applications. About 45.5% of the farmers received support from the brigades, at least once. The remaining farmers (54.5%) were not assisted by the brigades due to a lack of pesticides. Farmers estimate that the choice of any pesticide greatly depends upon its knock-down ability (57.5%) or the numbers of cadavers found after a treatment (42.5%). Most farmers (82%) consider the government to be responsible for locust and migrant grasshoppers control. On average, farmers were willing to pay US$ 1.00 per ha per year, to protect their crops.

  • pratiques paysannes et utilisation potentielle de Metarhizium Flavoviride gams rozsypal en lutte anti acridienne au niger
    International Journal of Tropical Insect Science, 1999
    Co-Authors: Idrissa Halidou Maiga, C. J. Lomer, O K Dourokpindou, J. Langewald
    Abstract:

    A socio-economic study was executed in South East Niger to determine the conditions under which a novel mycopesticide based on the fungus Metarhizium Flavoviride could be introduced for locust and grasshopper control as a possible alternative reducing the use of synthetic chemicals. From the interviews, all farmers estimated locusts and grasshoppers to be one of three major pests. The survey revealed that 93.8% of the farmers conduct collective pesticide applications. About 45.5% of the farmers received support from the brigades, at least once. The remaining farmers (54.5%) were not assisted by the brigades due to a lack of pesticides. Farmers estimate that the choice of any pesticide greatly depends upon its knock-down ability (57.5%) or the numbers of cadavers found after a treatment (42.5%). Most farmers (82%) consider the government to be responsible for locust and migrant grasshoppers control. On average, farmers were willing to pay US$ 1.00 per ha per year, to protect their crops.

  • Pratiques Paysannes et Utilisation Potentielle de Metarhizium Flavoviride Gams & Rozsypal en Lutte Anti-Acridienne au Niger
    International Journal of Tropical Insect Science, 1999
    Co-Authors: Idrissa Halidou Maiga, O.-k. Douro-kpindou, C. J. Lomer, J. Langewald
    Abstract:

    Une enquête a été réalisée en vue d’étudier les conditions socio-économiques et techniques dans lesquelles serait introduit un mycopesticide pour remplacer les produits chimiques utilisés contre les criquets. De cette étude il ressort que pour les gens enquêtés, les sauteriaux constituent un des trois principaux ravageurs de cultures. La lutte anti-acridienne se fait de manière collective (93,8% des cas) et 45,5% des paysans enquêtés affirment avoir bénéficié d’au moins une assistance de la brigade phytosanitaire du village. Les autres (54,5%) n’avaient pas pu en bénéficier à cause du manque de pesticides. Un pesticide est choisi en fonction de sa rapidité à tuer les criquets pour 57,5% des agriculteurs, et son efficacité (le nombre de cadavres observés après un traitement) pour 42,5% d’entre eux. La majorité (82%) des agriculteurs considèrent le traitement contre les acridiens comme une responsabilité du gouvernement. Les paysans pourraient en moyenne consentir 1 $ US par ha/an, pour la protection de leurs cultures. A socio-economic study was executed in South East Niger to determine the conditions under which a novel mycopesticide based on the fungus Metarhizium Flavoviride could be introduced for locust and grasshopper control as a possible alternative reducing the use of synthetic chemicals. From the interviews, all farmers estimated locusts and grasshoppers to be one of three major pests. The survey revealed that 93.8% of the farmers conduct collective pesticide applications. About 45.5% of the farmers received support from the brigades, at least once. The remaining farmers (54.5%) were not assisted by the brigades due to a lack of pesticides. Farmers estimate that the choice of any pesticide greatly depends upon its knock-down ability (57.5%) or the numbers of cadavers found after a treatment (42.5%). Most farmers (82%) consider the government to be responsible for locust and migrant grasshoppers control. On average, farmers were willing to pay US$ 1.00 per ha per year, to protect their crops.

  • Utilisation De Metarhizium Flavoviride Gams & Rozsypal Contre les Sauteriaux Dans des Essais Participatifs en Milieu Paysan au Niger
    International Journal of Tropical Insect Science, 1998
    Co-Authors: Idrissa Halidou Maiga, O.-k. Douro-kpindou, C. J. Lomer, J. Langewald
    Abstract:

    Les essais participatifs, sur l’utilisation d’un mycoinsecticide àbase despores du champignon entomopathogène Metarhizium Flavoviride en milieu paysan, ont été réalisés dans l’arrondissement de Gouré au Niger. Ces essais furent exécutés en collaboration avec le projet gestion des ressources naturelles financé par Africare. Dans une jachère d’à peu près 800 ha, six parcelles de 5 ha chacune, ont été délimitées dont trois d’entre elles ont été traitées avec une formulation de M. Flavoviride , souche IMI 330189, tandis que trois autres ont servi de témoins. La formulation fut à raison de 50 g de spores sèches par litre dans une suspension huileuse à base d’un mélange de pétrole et d’huile d’arachide et dans une proportion respective de 7:3. Cette formulation représente 2, 5×10^12 spores par litre. La pulvérisation a été effectuée à raison de 2 litres/ ha, au moyen d’atomiseurs à disque rotatif de type Micron ULVA. Directement et trois jours après l’application du mycoinsecticide, dans chacune des six parcelles, deux lots de 50 larves L3–L4 d’ Oedaleus senegalensis ont été ramassés et encagés. Une de cages était maintenue au champ et la seconde amenée à la station, afin de suivre la mortalité des acridiens. Les cages ont été suivies quotidiennement jusqu’au 14^me jour après le traitement. Les individus morts étaient mis en incubation dans des boîtes de Pétri avec une couche de papier mouchoir imbibée d’eau distillée, afin d’observer la sporulation du champignon sur les cadavres. Les échantillons de sauteriaux placés en cage ont donné une mortalité de 80%, 12 jours après l’application. Une différence significative a été notée entre les témoins et les parcelles traitées au niveau de la densité de population. Toutefois, la lenteur de l’action du champignon n’a pas permis une démonstration convaincante lors des visites des parcelles avec les paysans, puisque les larves de sauteriaux ayant atteint les stades L5 et adultes devenaient très mobiles. Cependant, les cadavres des sauteriaux collectés et encagés et surtout de ceux provenant des les parcelles traitées et mis en incubation ont permis une démonstration aux paysans, de la sporulation du champignon et de là l’action du mycoinsecticide. Les paysans étaient intéressés par le mycoinsecticide, mais ils restent réticents à s’acheter eux-mêmes un produit qui agit lentement. Participatory trials on the use of a mycoinsecticide based on spores of the entomopathogenic fungus Metarhizium Flavoviride were carried out to control grasshoppers on farmers’ plots at Gouré, Niger. The study was conducted in collaboration with the natural resources management project financed by Africare. From a fallow area of about 800 ha, six plots of 5 ha each were selected. Three of these plots were treated with M. Flavoviride , strain IM 330189, while the three remaining plots served as controls. An emulsion of the fungus was prepared with 50 g of dry spores mixed with paraffin and ground oil at a ratio of 7:3. This formulation represents a concentration of 2.5×10^12 spores per litre. The mycoinsecticide was applied at the rate of 2 litres/ha with a Micron ULVA sprayer. Immediately after spraying and three days later, two batches of 50 L4 and L5 Oedaleus senegalensis larvae were collected per plot and each batch kept in a separate cage. One of the two cages was kept in the experimental plot, whereas the second one was taken to the station, in order to follow the grasshoppers’ mortality. Cages were checked daily for two weeks starting from the day of fungus application, and insect mortality recorded. Dead insects were transferred into Petri dishes with moistened filter paper to allow the fungus to sporulate from the cadavers. Grasshoppers kept in cages suffered 80% mortality, 12 days after application. Reduction in grasshopper population density between treated and untreated plots was significantly different, but did not convince farmers, as full grown L5 larvae had emerged as adults and began migrating. However, cadavers collected from cages containing insects from treated plots allowed farmers to follow how the fungus sporulates and contaminates healthy grasshoppers. Farmers were interested in the product but were reluctant to buy a slow-acting insecticide.

  • utilisation de Metarhizium Flavoviride gams rozsypal contre les sauteriaux dans des essais participatifs en milieu paysan au niger
    International Journal of Tropical Insect Science, 1998
    Co-Authors: Idrissa Halidou Maiga, C. J. Lomer, O K Dourokpindou, J. Langewald
    Abstract:

    Les essais participatifs, sur l’utilisation d’un mycoinsecticide abase despores du champignon entomopathogene Metarhizium Flavoviride en milieu paysan, ont ete realises dans l’arrondissement de Goure au Niger. Ces essais furent executes en collaboration avec le projet gestion des ressources naturelles finance par Africare. Dans une jachere d’a peu pres 800 ha, six parcelles de 5 ha chacune, ont ete delimitees dont trois d’entre elles ont ete traitees avec une formulation de M. Flavoviride, souche IMI 330189, tandis que trois autres ont servi de temoins. La formulation fut a raison de 50 g de spores seches par litre dans une suspension huileuse a base d’un melange de petrole et d’huile d’arachide et dans une proportion respective de 7:3. Cette formulation represente 2, 5×1012 spores par litre. La pulverisation a ete effectuee a raison de 2 litres/ ha, au moyen d’atomiseurs a disque rotatif de type Micron ULVA. Directement et trois jours apres l’application du mycoinsecticide, dans chacune des six parcelles, deux lots de 50 larves L3–L4 d’Oedaleus senegalensis ont ete ramasses et encages. Une de cages etait maintenue au champ et la seconde amenee a la station, afin de suivre la mortalite des acridiens. Les cages ont ete suivies quotidiennement jusqu’au 14me jour apres le traitement. Les individus morts etaient mis en incubation dans des boites de Petri avec une couche de papier mouchoir imbibee d’eau distillee, afin d’observer la sporulation du champignon sur les cadavres. Les echantillons de sauteriaux places en cage ont donne une mortalite de 80%, 12 jours apres l’application. Une difference significative a ete notee entre les temoins et les parcelles traitees au niveau de la densite de population. Toutefois, la lenteur de l’action du champignon n’a pas permis une demonstration convaincante lors des visites des parcelles avec les paysans, puisque les larves de sauteriaux ayant atteint les stades L5 et adultes devenaient tres mobiles. Cependant, les cadavres des sauteriaux collectes et encages et surtout de ceux provenant des les parcelles traitees et mis en incubation ont permis une demonstration aux paysans, de la sporulation du champignon et de la l’action du mycoinsecticide. Les paysans etaient interesses par le mycoinsecticide, mais ils restent reticents a s’acheter eux-memes un produit qui agit lentement.

J. Langewald - One of the best experts on this subject based on the ideXlab platform.

  • pratiques paysannes et utilisation potentielle de Metarhizium Flavoviride gams rozsypal en lutte anti acridienne au niger
    International Journal of Tropical Insect Science, 1999
    Co-Authors: Idrissa Halidou Maiga, C. J. Lomer, O K Dourokpindou, J. Langewald
    Abstract:

    A socio-economic study was executed in South East Niger to determine the conditions under which a novel mycopesticide based on the fungus Metarhizium Flavoviride could be introduced for locust and grasshopper control as a possible alternative reducing the use of synthetic chemicals. From the interviews, all farmers estimated locusts and grasshoppers to be one of three major pests. The survey revealed that 93.8% of the farmers conduct collective pesticide applications. About 45.5% of the farmers received support from the brigades, at least once. The remaining farmers (54.5%) were not assisted by the brigades due to a lack of pesticides. Farmers estimate that the choice of any pesticide greatly depends upon its knock-down ability (57.5%) or the numbers of cadavers found after a treatment (42.5%). Most farmers (82%) consider the government to be responsible for locust and migrant grasshoppers control. On average, farmers were willing to pay US$ 1.00 per ha per year, to protect their crops.

  • Pratiques Paysannes et Utilisation Potentielle de Metarhizium Flavoviride Gams & Rozsypal en Lutte Anti-Acridienne au Niger
    International Journal of Tropical Insect Science, 1999
    Co-Authors: Idrissa Halidou Maiga, O.-k. Douro-kpindou, C. J. Lomer, J. Langewald
    Abstract:

    A socio-economic study was executed in South East Niger to determine the conditions under which a novel mycopesticide based on the fungus Metarhizium Flavoviride could be introduced for locust and grasshopper control as a possible alternative reducing the use of synthetic chemicals. From the interviews, all farmers estimated locusts and grasshoppers to be one of three major pests. The survey revealed that 93.8% of the farmers conduct collective pesticide applications. About 45.5% of the farmers received support from the brigades, at least once. The remaining farmers (54.5%) were not assisted by the brigades due to a lack of pesticides. Farmers estimate that the choice of any pesticide greatly depends upon its knock-down ability (57.5%) or the numbers of cadavers found after a treatment (42.5%). Most farmers (82%) consider the government to be responsible for locust and migrant grasshoppers control. On average, farmers were willing to pay US$ 1.00 per ha per year, to protect their crops.

  • Pratiques Paysannes et Utilisation Potentielle de Metarhizium Flavoviride Gams & Rozsypal en Lutte Anti-Acridienne au Niger
    International Journal of Tropical Insect Science, 1999
    Co-Authors: Idrissa Halidou Maiga, O.-k. Douro-kpindou, C. J. Lomer, J. Langewald
    Abstract:

    Une enquête a été réalisée en vue d’étudier les conditions socio-économiques et techniques dans lesquelles serait introduit un mycopesticide pour remplacer les produits chimiques utilisés contre les criquets. De cette étude il ressort que pour les gens enquêtés, les sauteriaux constituent un des trois principaux ravageurs de cultures. La lutte anti-acridienne se fait de manière collective (93,8% des cas) et 45,5% des paysans enquêtés affirment avoir bénéficié d’au moins une assistance de la brigade phytosanitaire du village. Les autres (54,5%) n’avaient pas pu en bénéficier à cause du manque de pesticides. Un pesticide est choisi en fonction de sa rapidité à tuer les criquets pour 57,5% des agriculteurs, et son efficacité (le nombre de cadavres observés après un traitement) pour 42,5% d’entre eux. La majorité (82%) des agriculteurs considèrent le traitement contre les acridiens comme une responsabilité du gouvernement. Les paysans pourraient en moyenne consentir 1 $ US par ha/an, pour la protection de leurs cultures. A socio-economic study was executed in South East Niger to determine the conditions under which a novel mycopesticide based on the fungus Metarhizium Flavoviride could be introduced for locust and grasshopper control as a possible alternative reducing the use of synthetic chemicals. From the interviews, all farmers estimated locusts and grasshoppers to be one of three major pests. The survey revealed that 93.8% of the farmers conduct collective pesticide applications. About 45.5% of the farmers received support from the brigades, at least once. The remaining farmers (54.5%) were not assisted by the brigades due to a lack of pesticides. Farmers estimate that the choice of any pesticide greatly depends upon its knock-down ability (57.5%) or the numbers of cadavers found after a treatment (42.5%). Most farmers (82%) consider the government to be responsible for locust and migrant grasshoppers control. On average, farmers were willing to pay US$ 1.00 per ha per year, to protect their crops.

  • Utilisation De Metarhizium Flavoviride Gams & Rozsypal Contre les Sauteriaux Dans des Essais Participatifs en Milieu Paysan au Niger
    International Journal of Tropical Insect Science, 1998
    Co-Authors: Idrissa Halidou Maiga, O.-k. Douro-kpindou, C. J. Lomer, J. Langewald
    Abstract:

    Les essais participatifs, sur l’utilisation d’un mycoinsecticide àbase despores du champignon entomopathogène Metarhizium Flavoviride en milieu paysan, ont été réalisés dans l’arrondissement de Gouré au Niger. Ces essais furent exécutés en collaboration avec le projet gestion des ressources naturelles financé par Africare. Dans une jachère d’à peu près 800 ha, six parcelles de 5 ha chacune, ont été délimitées dont trois d’entre elles ont été traitées avec une formulation de M. Flavoviride , souche IMI 330189, tandis que trois autres ont servi de témoins. La formulation fut à raison de 50 g de spores sèches par litre dans une suspension huileuse à base d’un mélange de pétrole et d’huile d’arachide et dans une proportion respective de 7:3. Cette formulation représente 2, 5×10^12 spores par litre. La pulvérisation a été effectuée à raison de 2 litres/ ha, au moyen d’atomiseurs à disque rotatif de type Micron ULVA. Directement et trois jours après l’application du mycoinsecticide, dans chacune des six parcelles, deux lots de 50 larves L3–L4 d’ Oedaleus senegalensis ont été ramassés et encagés. Une de cages était maintenue au champ et la seconde amenée à la station, afin de suivre la mortalité des acridiens. Les cages ont été suivies quotidiennement jusqu’au 14^me jour après le traitement. Les individus morts étaient mis en incubation dans des boîtes de Pétri avec une couche de papier mouchoir imbibée d’eau distillée, afin d’observer la sporulation du champignon sur les cadavres. Les échantillons de sauteriaux placés en cage ont donné une mortalité de 80%, 12 jours après l’application. Une différence significative a été notée entre les témoins et les parcelles traitées au niveau de la densité de population. Toutefois, la lenteur de l’action du champignon n’a pas permis une démonstration convaincante lors des visites des parcelles avec les paysans, puisque les larves de sauteriaux ayant atteint les stades L5 et adultes devenaient très mobiles. Cependant, les cadavres des sauteriaux collectés et encagés et surtout de ceux provenant des les parcelles traitées et mis en incubation ont permis une démonstration aux paysans, de la sporulation du champignon et de là l’action du mycoinsecticide. Les paysans étaient intéressés par le mycoinsecticide, mais ils restent réticents à s’acheter eux-mêmes un produit qui agit lentement. Participatory trials on the use of a mycoinsecticide based on spores of the entomopathogenic fungus Metarhizium Flavoviride were carried out to control grasshoppers on farmers’ plots at Gouré, Niger. The study was conducted in collaboration with the natural resources management project financed by Africare. From a fallow area of about 800 ha, six plots of 5 ha each were selected. Three of these plots were treated with M. Flavoviride , strain IM 330189, while the three remaining plots served as controls. An emulsion of the fungus was prepared with 50 g of dry spores mixed with paraffin and ground oil at a ratio of 7:3. This formulation represents a concentration of 2.5×10^12 spores per litre. The mycoinsecticide was applied at the rate of 2 litres/ha with a Micron ULVA sprayer. Immediately after spraying and three days later, two batches of 50 L4 and L5 Oedaleus senegalensis larvae were collected per plot and each batch kept in a separate cage. One of the two cages was kept in the experimental plot, whereas the second one was taken to the station, in order to follow the grasshoppers’ mortality. Cages were checked daily for two weeks starting from the day of fungus application, and insect mortality recorded. Dead insects were transferred into Petri dishes with moistened filter paper to allow the fungus to sporulate from the cadavers. Grasshoppers kept in cages suffered 80% mortality, 12 days after application. Reduction in grasshopper population density between treated and untreated plots was significantly different, but did not convince farmers, as full grown L5 larvae had emerged as adults and began migrating. However, cadavers collected from cages containing insects from treated plots allowed farmers to follow how the fungus sporulates and contaminates healthy grasshoppers. Farmers were interested in the product but were reluctant to buy a slow-acting insecticide.

  • utilisation de Metarhizium Flavoviride gams rozsypal contre les sauteriaux dans des essais participatifs en milieu paysan au niger
    International Journal of Tropical Insect Science, 1998
    Co-Authors: Idrissa Halidou Maiga, C. J. Lomer, O K Dourokpindou, J. Langewald
    Abstract:

    Les essais participatifs, sur l’utilisation d’un mycoinsecticide abase despores du champignon entomopathogene Metarhizium Flavoviride en milieu paysan, ont ete realises dans l’arrondissement de Goure au Niger. Ces essais furent executes en collaboration avec le projet gestion des ressources naturelles finance par Africare. Dans une jachere d’a peu pres 800 ha, six parcelles de 5 ha chacune, ont ete delimitees dont trois d’entre elles ont ete traitees avec une formulation de M. Flavoviride, souche IMI 330189, tandis que trois autres ont servi de temoins. La formulation fut a raison de 50 g de spores seches par litre dans une suspension huileuse a base d’un melange de petrole et d’huile d’arachide et dans une proportion respective de 7:3. Cette formulation represente 2, 5×1012 spores par litre. La pulverisation a ete effectuee a raison de 2 litres/ ha, au moyen d’atomiseurs a disque rotatif de type Micron ULVA. Directement et trois jours apres l’application du mycoinsecticide, dans chacune des six parcelles, deux lots de 50 larves L3–L4 d’Oedaleus senegalensis ont ete ramasses et encages. Une de cages etait maintenue au champ et la seconde amenee a la station, afin de suivre la mortalite des acridiens. Les cages ont ete suivies quotidiennement jusqu’au 14me jour apres le traitement. Les individus morts etaient mis en incubation dans des boites de Petri avec une couche de papier mouchoir imbibee d’eau distillee, afin d’observer la sporulation du champignon sur les cadavres. Les echantillons de sauteriaux places en cage ont donne une mortalite de 80%, 12 jours apres l’application. Une difference significative a ete notee entre les temoins et les parcelles traitees au niveau de la densite de population. Toutefois, la lenteur de l’action du champignon n’a pas permis une demonstration convaincante lors des visites des parcelles avec les paysans, puisque les larves de sauteriaux ayant atteint les stades L5 et adultes devenaient tres mobiles. Cependant, les cadavres des sauteriaux collectes et encages et surtout de ceux provenant des les parcelles traitees et mis en incubation ont permis une demonstration aux paysans, de la sporulation du champignon et de la l’action du mycoinsecticide. Les paysans etaient interesses par le mycoinsecticide, mais ils restent reticents a s’acheter eux-memes un produit qui agit lentement.

O.-k. Douro-kpindou - One of the best experts on this subject based on the ideXlab platform.

  • Pratiques Paysannes et Utilisation Potentielle de Metarhizium Flavoviride Gams & Rozsypal en Lutte Anti-Acridienne au Niger
    International Journal of Tropical Insect Science, 1999
    Co-Authors: Idrissa Halidou Maiga, O.-k. Douro-kpindou, C. J. Lomer, J. Langewald
    Abstract:

    Une enquête a été réalisée en vue d’étudier les conditions socio-économiques et techniques dans lesquelles serait introduit un mycopesticide pour remplacer les produits chimiques utilisés contre les criquets. De cette étude il ressort que pour les gens enquêtés, les sauteriaux constituent un des trois principaux ravageurs de cultures. La lutte anti-acridienne se fait de manière collective (93,8% des cas) et 45,5% des paysans enquêtés affirment avoir bénéficié d’au moins une assistance de la brigade phytosanitaire du village. Les autres (54,5%) n’avaient pas pu en bénéficier à cause du manque de pesticides. Un pesticide est choisi en fonction de sa rapidité à tuer les criquets pour 57,5% des agriculteurs, et son efficacité (le nombre de cadavres observés après un traitement) pour 42,5% d’entre eux. La majorité (82%) des agriculteurs considèrent le traitement contre les acridiens comme une responsabilité du gouvernement. Les paysans pourraient en moyenne consentir 1 $ US par ha/an, pour la protection de leurs cultures. A socio-economic study was executed in South East Niger to determine the conditions under which a novel mycopesticide based on the fungus Metarhizium Flavoviride could be introduced for locust and grasshopper control as a possible alternative reducing the use of synthetic chemicals. From the interviews, all farmers estimated locusts and grasshoppers to be one of three major pests. The survey revealed that 93.8% of the farmers conduct collective pesticide applications. About 45.5% of the farmers received support from the brigades, at least once. The remaining farmers (54.5%) were not assisted by the brigades due to a lack of pesticides. Farmers estimate that the choice of any pesticide greatly depends upon its knock-down ability (57.5%) or the numbers of cadavers found after a treatment (42.5%). Most farmers (82%) consider the government to be responsible for locust and migrant grasshoppers control. On average, farmers were willing to pay US$ 1.00 per ha per year, to protect their crops.

  • Pratiques Paysannes et Utilisation Potentielle de Metarhizium Flavoviride Gams & Rozsypal en Lutte Anti-Acridienne au Niger
    International Journal of Tropical Insect Science, 1999
    Co-Authors: Idrissa Halidou Maiga, O.-k. Douro-kpindou, C. J. Lomer, J. Langewald
    Abstract:

    A socio-economic study was executed in South East Niger to determine the conditions under which a novel mycopesticide based on the fungus Metarhizium Flavoviride could be introduced for locust and grasshopper control as a possible alternative reducing the use of synthetic chemicals. From the interviews, all farmers estimated locusts and grasshoppers to be one of three major pests. The survey revealed that 93.8% of the farmers conduct collective pesticide applications. About 45.5% of the farmers received support from the brigades, at least once. The remaining farmers (54.5%) were not assisted by the brigades due to a lack of pesticides. Farmers estimate that the choice of any pesticide greatly depends upon its knock-down ability (57.5%) or the numbers of cadavers found after a treatment (42.5%). Most farmers (82%) consider the government to be responsible for locust and migrant grasshoppers control. On average, farmers were willing to pay US$ 1.00 per ha per year, to protect their crops.

  • Utilisation De Metarhizium Flavoviride Gams & Rozsypal Contre les Sauteriaux Dans des Essais Participatifs en Milieu Paysan au Niger
    International Journal of Tropical Insect Science, 1998
    Co-Authors: Idrissa Halidou Maiga, O.-k. Douro-kpindou, C. J. Lomer
    Abstract:

    Les essais participatifs, sur l’utilisation d’un mycoinsecticide abase despores du champignon entomopathogene Metarhizium Flavoviride en milieu paysan, ont ete realises dans l’arrondissement de Goure au Niger. Ces essais furent executes en collaboration avec le projet gestion des ressources naturelles finance par Africare. Dans une jachere d’a peu pres 800 ha, six parcelles de 5 ha chacune, ont ete delimitees dont trois d’entre elles ont ete traitees avec une formulation de M. Flavoviride, souche IMI 330189, tandis que trois autres ont servi de temoins. La formulation fut a raison de 50 g de spores seches par litre dans une suspension huileuse a base d’un melange de petrole et d’huile d’arachide et dans une proportion respective de 7:3. Cette formulation represente 2, 5×1012 spores par litre. La pulverisation a ete effectuee a raison de 2 litres/ ha, au moyen d’atomiseurs a disque rotatif de type Micron ULVA. Directement et trois jours apres l’application du mycoinsecticide, dans chacune des six parcelles, deux lots de 50 larves L3–L4 d’Oedaleus senegalensis ont ete ramasses et encages. Une de cages etait maintenue au champ et la seconde amenee a la station, afin de suivre la mortalite des acridiens. Les cages ont ete suivies quotidiennement jusqu’au 14me jour apres le traitement. Les individus morts etaient mis en incubation dans des boites de Petri avec une couche de papier mouchoir imbibee d’eau distillee, afin d’observer la sporulation du champignon sur les cadavres. Les echantillons de sauteriaux places en cage ont donne une mortalite de 80%, 12 jours apres l’application. Une difference significative a ete notee entre les temoins et les parcelles traitees au niveau de la densite de population. Toutefois, la lenteur de l’action du champignon n’a pas permis une demonstration convaincante lors des visites des parcelles avec les paysans, puisque les larves de sauteriaux ayant atteint les stades L5 et adultes devenaient tres mobiles. Cependant, les cadavres des sauteriaux collectes et encages et surtout de ceux provenant des les parcelles traitees et mis en incubation ont permis une demonstration aux paysans, de la sporulation du champignon et de la l’action du mycoinsecticide. Les paysans etaient interesses par le mycoinsecticide, mais ils restent reticents a s’acheter eux-memes un produit qui agit lentement.

  • Utilisation De Metarhizium Flavoviride Gams & Rozsypal Contre les Sauteriaux Dans des Essais Participatifs en Milieu Paysan au Niger
    International Journal of Tropical Insect Science, 1998
    Co-Authors: Idrissa Halidou Maiga, O.-k. Douro-kpindou, C. J. Lomer, J. Langewald
    Abstract:

    Les essais participatifs, sur l’utilisation d’un mycoinsecticide àbase despores du champignon entomopathogène Metarhizium Flavoviride en milieu paysan, ont été réalisés dans l’arrondissement de Gouré au Niger. Ces essais furent exécutés en collaboration avec le projet gestion des ressources naturelles financé par Africare. Dans une jachère d’à peu près 800 ha, six parcelles de 5 ha chacune, ont été délimitées dont trois d’entre elles ont été traitées avec une formulation de M. Flavoviride , souche IMI 330189, tandis que trois autres ont servi de témoins. La formulation fut à raison de 50 g de spores sèches par litre dans une suspension huileuse à base d’un mélange de pétrole et d’huile d’arachide et dans une proportion respective de 7:3. Cette formulation représente 2, 5×10^12 spores par litre. La pulvérisation a été effectuée à raison de 2 litres/ ha, au moyen d’atomiseurs à disque rotatif de type Micron ULVA. Directement et trois jours après l’application du mycoinsecticide, dans chacune des six parcelles, deux lots de 50 larves L3–L4 d’ Oedaleus senegalensis ont été ramassés et encagés. Une de cages était maintenue au champ et la seconde amenée à la station, afin de suivre la mortalité des acridiens. Les cages ont été suivies quotidiennement jusqu’au 14^me jour après le traitement. Les individus morts étaient mis en incubation dans des boîtes de Pétri avec une couche de papier mouchoir imbibée d’eau distillée, afin d’observer la sporulation du champignon sur les cadavres. Les échantillons de sauteriaux placés en cage ont donné une mortalité de 80%, 12 jours après l’application. Une différence significative a été notée entre les témoins et les parcelles traitées au niveau de la densité de population. Toutefois, la lenteur de l’action du champignon n’a pas permis une démonstration convaincante lors des visites des parcelles avec les paysans, puisque les larves de sauteriaux ayant atteint les stades L5 et adultes devenaient très mobiles. Cependant, les cadavres des sauteriaux collectés et encagés et surtout de ceux provenant des les parcelles traitées et mis en incubation ont permis une démonstration aux paysans, de la sporulation du champignon et de là l’action du mycoinsecticide. Les paysans étaient intéressés par le mycoinsecticide, mais ils restent réticents à s’acheter eux-mêmes un produit qui agit lentement. Participatory trials on the use of a mycoinsecticide based on spores of the entomopathogenic fungus Metarhizium Flavoviride were carried out to control grasshoppers on farmers’ plots at Gouré, Niger. The study was conducted in collaboration with the natural resources management project financed by Africare. From a fallow area of about 800 ha, six plots of 5 ha each were selected. Three of these plots were treated with M. Flavoviride , strain IM 330189, while the three remaining plots served as controls. An emulsion of the fungus was prepared with 50 g of dry spores mixed with paraffin and ground oil at a ratio of 7:3. This formulation represents a concentration of 2.5×10^12 spores per litre. The mycoinsecticide was applied at the rate of 2 litres/ha with a Micron ULVA sprayer. Immediately after spraying and three days later, two batches of 50 L4 and L5 Oedaleus senegalensis larvae were collected per plot and each batch kept in a separate cage. One of the two cages was kept in the experimental plot, whereas the second one was taken to the station, in order to follow the grasshoppers’ mortality. Cages were checked daily for two weeks starting from the day of fungus application, and insect mortality recorded. Dead insects were transferred into Petri dishes with moistened filter paper to allow the fungus to sporulate from the cadavers. Grasshoppers kept in cages suffered 80% mortality, 12 days after application. Reduction in grasshopper population density between treated and untreated plots was significantly different, but did not convince farmers, as full grown L5 larvae had emerged as adults and began migrating. However, cadavers collected from cages containing insects from treated plots allowed farmers to follow how the fungus sporulates and contaminates healthy grasshoppers. Farmers were interested in the product but were reluctant to buy a slow-acting insecticide.

  • Effects of the sunscreen oxybenzone on field efficacy and persistence of Metarhizium Flavoviride conidia against Kraussella amabile (Orthoptera: Acrididae) in Mali, West Africa
    Biocontrol Science and Technology, 1998
    Co-Authors: P. A. Shah, O.-k. Douro-kpindou, A. Sidibe, C. O. Daffé, H. Van Der. Pauuw, C. J. Lomer
    Abstract:

    A field trial was performed at Mourdiah, northwest Mali, to evaluate whether the performance of Metarhizium Flavoviride conidia would improve if 2% oxybenzone, an oil-soluble ultraviolet light protectant, was used. Conidia were applied in an ultra-low volume formulation against nymphs of the grasshopper Kraussella amabile . Mortality was assessed by collecting grasshoppers directly from field plots (sweep net samples) or by exposing untreated nymphs to sprayed vegetation for 48 h (field cage samples). For sweep net samples, the mortalities in M. Flavoviride treatments varied between 94.5 and 99.9% up to 7 days after treatment, while control mortalities were significantly lower (20.7-55.0%). There were no significant differences between M. Flavoviride treatments with or without oxybenzone. The average survival times were found to be significantly lower for fungal treatments (4.9 days) compared with the control treatment (11.8 days). W ith field cage samples, the mortality in M. Flavoviride treatments decli...

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  • limits to the negative logarithmic relationship between moisture content and longevity in conidia of Metarhizium Flavoviride
    Annals of Botany, 1998
    Co-Authors: T. D. Hong, Nina E. Jenkins, R H Ellis, D. Moore
    Abstract:

    Abstract Conidia of Metarhizium Flavoviride were hermetically stored at 50 °C and 14 moisture contents between 2.5 and 31.8% (fresh weight basis) for up to 146 d, and tested for germination on Sabouraud Dextrose Agar at 25 °C for 24 h. Survival of conidia conformed to cumulative negative normal distributions and all 14 survival curves could be constrained to a common origin. There was a negative logarithmic relation between longevity and conidia moisture content, but limits to the relation were detected: the lower-moisture-content limit was 4.6% [in equilibrium with 10.7% relative humidity (RH) at 20 °C], below which value further reduction in moisture content did not increase conidia longevity; and an upper-moisture-content limit between about 21.2 and 31.8% moisture content (between 77 and 90.0% equilibrium RH at 20 °C) above which conidia longevity no longer decreased. The observations could also be described by a negative semi-logarithmic relation between conidia longevity and equilibrium relative humidity. In this model, each reduction in equilibrium relative humidity by 11.2% within the range 10.7 to 80% RH doubled conidia longevity. The similarities in these relations, and the limits to these relations, between the conidia of this entomopathogenic fungus and the orthodox seeds of higher plants are discussed.

  • Viability of Stored Conidia of Metarhizium Flavoviride Gams and Rozsypal, Produced under Differing Culture Regimes and Stored with Clays
    Biocontrol Science and Technology, 1997
    Co-Authors: D. Moore, P. M. Higgins
    Abstract:

    Conidia of Metarhizium Flavoviride were cultured under a range of conditions and stored , with or without clays and silica gel , as powder or in oil . Fungal biomass was produced in shake flasks in liquid media containing nutrients before being added to sterilized rice for conidial production . Conidia pre - cultured under a low C:N ratio , or dried over a 9 - day period compared with 2 days before being placed in storage , showed greatest loss of viability . Conidia stored at 10 o C survived better than those stored at + 30 o C . A range of clays had no significant effect on storage of dried conidia but montmorillonite K10 clay was often harmful in terms of conidial viability . Conidia survived better when stored as dry powder than when stored in a mixture of mineral and vegetable oils . The addition of silica gel proved beneficial even when dried conidia were being stored .

  • Effects of Rehydration on the Conidial Viability of Metarhizium Flavoviride Mycopesticide Formulations
    Biocontrol Science and Technology, 1997
    Co-Authors: D. Moore, J. Langewald, F. Obognon
    Abstract:

    The rehydration of dried conidia of Metarhizium Flavoviride was investigated in an attempt to increase speed of kill of locusts and grasshoppers by formulations of this fungus. Conidia were dried t...

  • The effect of fatty, organic or phenolic acids on the germination of conidia of Metarhizium Flavoviride
    Mycological Research, 1997
    Co-Authors: S.e. Barnes, D. Moore
    Abstract:

    Conidia of Metarhizium Flavoviride were suspended in oil formulations and received fatty and other acids before germination. This was done by the acids being added either to the conidial suspensions before inoculation onto agar plates or directly into the agar before the conidia were applied. Certain acids of chain lengths C10 and below, including lactic, salicylic, caprylic and capric acids produced significant inhibition of germination when added to the oil formulations. When incorporated into the agar, all acids of C10 and below were inhibitory, with the exception of sebacic and succinic acids. Sebacic acid (a C10 saturated dicarboyxlic acid) and all the longer chain fatty acids sampled produced no inhibition of germination, either when added to the formulation or the agar. Tests were carried out on a sample of conidia which showed no germination; a few acids stimulated some germination. These included sebacic acid and longer chain fatty acids such as stearic and (inconsistently) lauric acids. Conidia from a long term storage experiment showed increased germination on the addition of stearic and/or lauric acids. The inhibitory effect of capric acid on germination was overcome by a 4–15 times higher concentration of stearic acid.

  • Effects of Moisture Content and Temperature on Storage of Metarhizium Flavoviride Conidia
    Biocontrol Science and Technology, 1996
    Co-Authors: D. Moore, O.-k. Douro-kpindou, Nina E. Jenkins, C. J. Lomer
    Abstract:

    The effects of moisture content and temperature on the medium-term (3-4 months) storage of conidia of Metarhizium Flavoviride were investigated. Conidia harvested after 24 days of culturing on rice showed greater tolerance to long storage than conidia from 12-day cultures. The moisture content of the conidia was of greatest importance; at harvest from the culture, conidial moisture contents could be 40%, while the optimal moisture content for storage was found to be 4-5%. Dried conidia stored in oil benefited from the addition of dried silica gel, as did conidia stored as powder. A range of mineral oils proved satisfactory for storage, and when dried silica gel was added to suspensions, germination levels were 79.8% after 105 days at 28-32 C. Dried conidia stored in oil maintained germination levels of up to 96 and 85% after 80 days at 10-14 C and 28-32 C respectively. Dried conidia stored as powder retained germination levels of 95% at 10-14 C, but only up to 27% at 28-32 C. In another experiment, dried ...