Biological control of the cassava mealybug, Phenacoccus manihoti (Hom., Pseudococcidae), by Epidinocarsis lopezi (Hym., Encyrtidae) in Malawi
From 1985 to 1989 five large scale surveys were made to document the spread of the cassava mealybug (CM) Phenacoccus manihoti Matile‐Ferrero (Hom., Pseudococcidae) and the releases and successful establishment of its exotic parasitoid Epidinocarsis lopezi (De Santis) (Hym., Encyrtidae) through most...
| Main Authors: | , , , , , , |
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| Format: | Journal Article |
| Language: | Inglés |
| Published: |
Informa UK Limited
1991
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| Subjects: | |
| Online Access: | https://hdl.handle.net/10568/100011 |
| _version_ | 1855543704105779200 |
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| author | Neuenschwander, Peter Borowka, R. Phiri, G. Hammans, H. Nyirenda, S. Kapeya, E.H. Gadabu, A. |
| author_browse | Borowka, R. Gadabu, A. Hammans, H. Kapeya, E.H. Neuenschwander, Peter Nyirenda, S. Phiri, G. |
| author_facet | Neuenschwander, Peter Borowka, R. Phiri, G. Hammans, H. Nyirenda, S. Kapeya, E.H. Gadabu, A. |
| author_sort | Neuenschwander, Peter |
| collection | Repository of Agricultural Research Outputs (CGSpace) |
| description | From 1985 to 1989 five large scale surveys were made to document the spread of the cassava mealybug (CM) Phenacoccus manihoti Matile‐Ferrero (Hom., Pseudococcidae) and the releases and successful establishment of its exotic parasitoid Epidinocarsis lopezi (De Santis) (Hym., Encyrtidae) through most cassava‐growing areas of Malawi. In a multiple regression analysis involving 29 meteorological, agronomic and plant variables from 476 fields, the duration of E. lopezi's presence was the major factor influencing CM population densities. In the first year the CM was recorded in a particular place, 25% of all tips had more than 100 CM. Wherever E. lopezi had been present for two years or more, CM populations were reduced on average seven times and tips infested with more than 100 CM became rare (1%). In parallel, damage on cassava tips stabilized at a low level. Similarly, along Lake Malawi, 84.9% of all tips had more than 10 CM in 1986; this value stabilized at 3.3%‐4.0% in 1988–1989. Indigenous coccinellids were often abundant in the first year of the CM infestation, but their populations collapsed later, while the frequency of fields with E. lopezi increased. In 1987, farmers abandoned 28.4% of all fields where E. lopezi was just introduced as compared with 2.7% where the parasitoid had been present for two years or more. Overall, satisfactory control was achieved by E. lopezi in all but a few fields concentrated on extremely poor soils characterized by sand dune vegetation. The socioeconomic implications of this ongoing and apparently successful biological control program are discussed. |
| format | Journal Article |
| id | CGSpace100011 |
| institution | CGIAR Consortium |
| language | Inglés |
| publishDate | 1991 |
| publishDateRange | 1991 |
| publishDateSort | 1991 |
| publisher | Informa UK Limited |
| publisherStr | Informa UK Limited |
| record_format | dspace |
| spelling | CGSpace1000112024-05-15T05:12:21Z Biological control of the cassava mealybug, Phenacoccus manihoti (Hom., Pseudococcidae), by Epidinocarsis lopezi (Hym., Encyrtidae) in Malawi Neuenschwander, Peter Borowka, R. Phiri, G. Hammans, H. Nyirenda, S. Kapeya, E.H. Gadabu, A. biological control cassava mealybugs epidinocarsis lopezi From 1985 to 1989 five large scale surveys were made to document the spread of the cassava mealybug (CM) Phenacoccus manihoti Matile‐Ferrero (Hom., Pseudococcidae) and the releases and successful establishment of its exotic parasitoid Epidinocarsis lopezi (De Santis) (Hym., Encyrtidae) through most cassava‐growing areas of Malawi. In a multiple regression analysis involving 29 meteorological, agronomic and plant variables from 476 fields, the duration of E. lopezi's presence was the major factor influencing CM population densities. In the first year the CM was recorded in a particular place, 25% of all tips had more than 100 CM. Wherever E. lopezi had been present for two years or more, CM populations were reduced on average seven times and tips infested with more than 100 CM became rare (1%). In parallel, damage on cassava tips stabilized at a low level. Similarly, along Lake Malawi, 84.9% of all tips had more than 10 CM in 1986; this value stabilized at 3.3%‐4.0% in 1988–1989. Indigenous coccinellids were often abundant in the first year of the CM infestation, but their populations collapsed later, while the frequency of fields with E. lopezi increased. In 1987, farmers abandoned 28.4% of all fields where E. lopezi was just introduced as compared with 2.7% where the parasitoid had been present for two years or more. Overall, satisfactory control was achieved by E. lopezi in all but a few fields concentrated on extremely poor soils characterized by sand dune vegetation. The socioeconomic implications of this ongoing and apparently successful biological control program are discussed. 1991-01 2019-03-03T05:54:44Z 2019-03-03T05:54:44Z Journal Article https://hdl.handle.net/10568/100011 en Limited Access Informa UK Limited Neuenschwander, P., Borowka, R., Phiri, G., Hammans, H., Nyirenda, S., Kapeya, E.H. & Gadabu, A. (1991). Biological control of the cassava mealybug Phenacoccus manihoti (Hom., Pseudococcidae) by Epidinocarsis lopezi (Hym., Encyrtidae) in Malawi. Biocontrol Science and Technology, 1(4), 297-310. |
| spellingShingle | biological control cassava mealybugs epidinocarsis lopezi Neuenschwander, Peter Borowka, R. Phiri, G. Hammans, H. Nyirenda, S. Kapeya, E.H. Gadabu, A. Biological control of the cassava mealybug, Phenacoccus manihoti (Hom., Pseudococcidae), by Epidinocarsis lopezi (Hym., Encyrtidae) in Malawi |
| title | Biological control of the cassava mealybug, Phenacoccus manihoti (Hom., Pseudococcidae), by Epidinocarsis lopezi (Hym., Encyrtidae) in Malawi |
| title_full | Biological control of the cassava mealybug, Phenacoccus manihoti (Hom., Pseudococcidae), by Epidinocarsis lopezi (Hym., Encyrtidae) in Malawi |
| title_fullStr | Biological control of the cassava mealybug, Phenacoccus manihoti (Hom., Pseudococcidae), by Epidinocarsis lopezi (Hym., Encyrtidae) in Malawi |
| title_full_unstemmed | Biological control of the cassava mealybug, Phenacoccus manihoti (Hom., Pseudococcidae), by Epidinocarsis lopezi (Hym., Encyrtidae) in Malawi |
| title_short | Biological control of the cassava mealybug, Phenacoccus manihoti (Hom., Pseudococcidae), by Epidinocarsis lopezi (Hym., Encyrtidae) in Malawi |
| title_sort | biological control of the cassava mealybug phenacoccus manihoti hom pseudococcidae by epidinocarsis lopezi hym encyrtidae in malawi |
| topic | biological control cassava mealybugs epidinocarsis lopezi |
| url | https://hdl.handle.net/10568/100011 |
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