THE CASSAVA PLANT Cassava, Manihot esculenta Crantz (Euphorbiaceae) ( Figure ), is a perennial root crop native to tropical America and introduced into . Abstract: The cassava mealybug Phenacoccus manihoti (Hemiptera: Pseudococcidae) feeds by sucking the sap of cassava plants, causing damage directly by. Abstract: The cassava mealybug Phenacoccus manihoti (Hemiptera: Pseudococcidae) feeds cassava plants, causing damage directly by sucking the sap and.
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Eggs are oblong, golden yellow and enclosed in woolly ovisacs located at the posterior end of the adult females. Length and breadth measurements are 0. Antennae are 6-segmented in first instars and 9-segmented in subsequent instars.
Body length and breadth measurements are, respectively, 0. Adult females of the cassava mealybug are ovoid, rose-pink and dusted with white, powdery wax; the eyes are relatively prominent, legs are well developed and of equal size Matile-Ferrero, The mealybug’s body segmentation is apparent. Body segments bear very short lateral and caudal white wax filaments in the form of swellings that produce a toothed appearance to the body outline.
All of the microscopic features listed above as typical for genus Phenacoccus are present in P. Other important characters of P. The above characters will facilitate recognition of many Phenacoccus species, especially the economically important ones. The lanceolate setae are especially distinctive for this genus. Regional keys to mealybug faunas, such as the one provided by Williams and Granara de Willinkshould, however, be used to support an identification of Phenacoccus, as some species have only a few of the morphological features which are typically found in this genus.
A useful key to identify Meaoybug. The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.
On the basis of the exotic origin and rapid spread of the cassava mealybug in Africa, classical biological control has been the main and most appropriate approach to the pest problem. Among several natural mealyybug introduced to combat the pest Herren and Lema, ; Lema and Herren, ; Herren et al.
1. Cassava and mealybugs
Herren and Neuenschwander reviewed the biological control campaign against cassava mealybug in Africa. It was introduced to Nigeria in and is now established in at least 26 African countries Ganga, ; Herren et al.
The biological and ecological impact cassaba A. In some studies, the results indicate a successful role of A. Large-scale and sustained field studies have, however, recorded excellent biological control of the pest by A.
Ants attending mealybugs for their honeydew are known to defend the pests from natural enemies that would otherwise attack them. They have been observed interfering with biological control of cassava mealybug in Ghana Cudjoe et al. It may be advisable to discourage ants in cassava fields if this becomes a problem. The economic impact of biological control of the cassava mealybug, mainly by A.
The benefit to cost ratio of biological control by Apoanagyrus Epidinocarsis lopezi was calculated as at least Where the soil is very infertile, however, biological control has been shown to be unsatisfactory, unless it can be complemented by cultural practices such as soil improvement Neuenschwander et al. The coccinellid Hyperaspis notata is associated with the mealybugs P.
It was brought to Africa to help control the accidentally introduced P. Immersion of cassava cuttings in manipueira a liquid extract from cassava roots for 60 minutes was found caesava significantly reduce infestation Razafindrakoto et al. Three NKWE treatments at weekly intervals protected cassava against established early instar nymphs; however, some phytotoxicity was observed.
Cassava contains two significant compounds whose levels increase in response to mealybug infestation. Cyanide content acts as a phagostimulant for the mealybug, whereas rutin has an antibiotic effect on the pest. It was found that the use of mulch and manure increased cassava resistance against mealybug infestation Tertuliano et al. Use of manure or other fertilizers can result in a reduction in the mealybug population because improved nutrition results in the production of larger parasitoid wasps with higher fertility levels Schulthess et al.
Mulch and fertilizer use also enhances the cxssava properties of cassava against mealybug infestation Tertuliano et al. Akinlosotu TA; Leuschner K, Outbreak of two new cassava pests Mononychellus tanajoa and Phenacoccus manihoti in southwestern Nigeria.
Tropical Pest Management, 27 2: A systematic catalogue of the mealybugs of the world Insecta: Pseudococcidae and Putoidae with data on geographical distribution, host plants, biology and economic importance. Andover, UK; Intercept Limited, pp. Ben-Dov Y; German V, Laboratory and field parasitism by Epidinocarsis Apoanagyrus lopezi Hym.: Encyrtidae an exotic auxillary introduced into the Congo for the control of Phenacoccus manihoti Hom.: The insects associated with the cassava mealybug, Phenacoccus manihoti Homoptera: Pseudococcidae in Congo, five years after the introduction of Epidinocarsis lopezi Mfalybug Annales de la Societe Entomologique de France, 25 3: Une nouveau ravageur du manioc au Rwanda: Bulletin Agricole du Rwanda, Juillet Fighting African cassava pests from the air.
The natural enemy complex of cassava mealybug, Phenacoccus manihoti Hom. Coccoidea Pseudococcidae in Gabon. Annales de la Societe Entomologique de France, 22 1: Experiments on the biological control of the cassava mealybug in Gabon: Encyrtidae and competitive displacement of local parasitoids. La lutte contre la cochenille du manioc en Afrique.
Cahiers de la Recherche Developpement No. Biological control of the cassava mealybug, Phenacoccus manihoti Homoptera: Pseudococcidaein Zambia.
Biological Mdalybug, 4 3: An account of cassava mealybugs Mealhbug Pseudococcidae with a description of a new species.
Bulletin of Entomological Research, 71 2: Experimental determination of the efficiency of indigenous and exotic natural enemies of the cassava mealybug, Phenacoccus manihoti Mat.
Journal of Applied Entomology, 1: Interference by ants in biological control of the cassava mealybug Phenacoccus manihoti Hemiptera: Bulletin of Entomological Research, 83 1: First record of cassava mealybug, Phenacoccus manihoti Hemiptera: Pseudococcidaein Malaysia.
European and Mediterranean Plant Protection Organization. Bioecology of the casava mealybug Phenacoccus manihoti Hom. Pseudococcidae in the People’s Republic of Congo.
II — Variations in abundance and regulation factors. Agronomie Tropicale, 36 4: Fabres G; Boussiengue J, Agronomie Tropicale, 36 1: Fabres G; Kiyindou A, Comparison of the biotic potential of two coccinellids Exochomus flaviventris and Hyperaspis senegalensis hottentotta, Col.
Cassava-Mealybug interactions – 1. Cassava and mealybugs – IRD Éditions
Coccinellidaepredators of Phenacoccus manihoti Hom. Pseudococcidae in the Congo. Acta Oecologica, Oecologia Applicata, 6 4: Fabres G; Matile-Ferrero D, Natural enemies attacking the cassava mealybug Phenacoccus manihoti Hom. Coccoidea Pseudococcidae in the People’s Republic of Congo. The components of the entomocoenose and their interrelations. Annales de la Societe Entomologique de France, 16 4: Reflections on the acclimatization of exotic entomophages for the regulation of populations of the cassava mealybug in the Congo.
Bulletin de la Societe Zoologique de France, 1: New contribution to the study of scale insects from Brazilian Amazonia Homoptera: Annales de la Societe Entomologique de France, 24 1: Pseudococcidae par un entomophage exotique Epidinocarsis lopezi De Santis Hym. Encyrtidae en Republique Populaire du Congo. First record of the cassava mealybug, Phenacoccus manihoti Meqlybug Homoptera: Pseudococcidaefrom Zimbabwe. African Entomology, 2 2: Goergen G; Neuenschwander P,