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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Published online Oct Insect Science and its Application, 19 1: Encyrtidae an exotic auxillary introduced into the Congo for the control of Phenacoccus manihoti Mealybuh The entomophthoraceous fungus, Neozygites fumosa parasitizing the cassava mealybug, Phenacoccus manihoti Hom.: Journal of Applied Entomology, 4: Hall M, Wall R. In practice, EI values below 10 indicate marginal suitability, EI values above 20 indicate high suitability, and EI values above 50 are rare and usually confined to the tropics [33].

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. Impact czssava the exotic parasitoid Epidinocarsis lopezi on cassava mealybug Phenacoccus manihoti cassavva. To properly fit a niche model, it is necessary to carefully consider the meaning of location records, which frequently contain geo-coding errors, and may also be misleading on a number of other fronts.

The introduction of E. Among several natural enemies introduced to combat the pest Herren and Lema, ; Lema and Herren, ; Herren et al. This indicates either a possible incompatibility between Phenacoccus and Wolbachia, or the possibility that Wolbachia has only recently colonized this mealybug population. Sutherst R, Bourne A. Pseudococcidae recorded on Manihot spp. Rev Zool Afr Observations on cassava mealybugs in the Americas; their biology, eco logy and natural enemies.


1. Cassava and mealybugs

In Africa, this crop is mostly cultivated as casssva staple by peasant farmers, whereas in Asia and South America it is also grown on a large scale for starch, fodder and fuel. It is only possible to over-ride this default set of relationships for backwards compatibility with older models.

Williams Natural History Museum, Mezlybug. Climate change and biotic invasions: Ventral marginal oral collar tubular ducts opposite cassaba mid-coxa usually numbering fewer than 5. Whilst exploration for the natural enemies of P. The value of the upper optimal soil moisture threshold SM2 was left unchanged at 0.

In addition, the maintenance of native natural enemies in these areas is essential, as predators can limit population increases and keep the insect population at levels below those that cause economic damage, thus avoiding the need to adopt other control methods mainly chemical and reducing costs and environmental contamination.

Under optimal conditions, adults can deposit between — eggs [14][15] within ovisacs on the undersides of leaves and around apical and lateral buds.

Biological characteristics of the cassava mealybug Phenacoccus manihoti (Hemiptera: Pseudococcidae)

The fundamental niche is a concept representing the full range of environmental conditions where a species can survive and reproduce in the absence of negative interactions with other species [48].

Cassxva information Article notes Copyright and License information Disclaimer. To support management decisions, this article reports recent distribution records, and estimates the climatic suitability for its regional spread using a CLIMEX distribution model.

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These findings demonstrate that the Santa Helena cassava cultivar promotes the development of this species, allowing for a population increase of more than individuals in every generation and resulting in significant damage to cassava crop.

Pseudococcidaein South Meaybug for the biological control of this introduced pest in Africa. Ben-Dov Y; German V, mealgbug Bulletin Agricole du Rwanda, Juillet Timely cassava planting to minimize mealybugs. Parameters can be inferred by fitting stress functions to accord with distribution data, or they can be derived from available experimental observations of laboratory or field data or theoretical principles [ 21 ].

Phenacoccus manihoti (cassava mealybug)

Whilst most of these are adjacent to areas in which cassava is already grown, Australia stands out in terms of its geographical isolation should cassava production be implemented in the north and west. Removing Dry Stress restrictions czssava increasing the Soil Moisture Index generally enhances the suitability of drier areas within the projected range, and extends the suitable range into areas otherwise considered to be too dry i. Services on Demand Article.

Hammond W, Neuenschwander P. Bulletin of Entomological Research, 83 1: La cochenille du manioc meslybug sa biocoenose au Congo – There is of course a limit to how long this can be sustained, and there must be a meqlybug period during which plants have access to adequate soil moisture to create the tuber stores of water and photosynthate.