Native phytoseiid mites as indicators of non-target eVects of the introduction of Typhlodromalus aripo for the biological control of cassava green mite in Africa

Article purchasedThe need to evaluate non-target effects of classical biological control of arthropod pests has received considerable attention in recent years. We determined with repeated field surveys the changes in abundance and distribution of the phytoseiid mite fauna in cassava fields resulting from the introduction of the neotropical phytoseiid Typhlodromalus aripo into two countries—Malawi and Mozambique—in southern Africa for the biological control of Mononychellus tanajoa. Typhlodromalus aripo abundance was similar, while the abundance of the target pest M. tanajoa declined progressively, during the 2 years after the introduction of T. aripo into the target countries. We did not detect any changes in the abundance of the most common native phytoseiids mites—Euseius baetae, Euseius bwende and Ueckermannseius saltus—on cassava in Mozambique. In contrast, the abundance of two of the most common native phytoseiids, Euseius fustis and Iphiseius degenerans, on cassava in Malawi were apparently facilitated—i.e., their abundance was enhanced by the introduction of T. aripo; while the abundance of a third species, U. saltus, was not affected. For only one species, E. baetae, within-plant distribution shifted to the lower parts of the cassava canopy as a result of the introduction of T. aripo, which resides in the upper parts of the cassava canopy, but without any measurable negative effects on biological control of M. tanajoa. While the overall abundance of phytoseiid mites found on non-cassava vegetation was not affected by T. aripo introduction, there were some changes in relative abundance of some species in Malawi. Possible mechanism for the increase in abundance of I. degenerans and E. fustis in Malawi, and changes in within-plant distribution of E. baetae and I. degenerans in Mozambique and Malawi, respectively, are discussed. The methodology developed for assessing potential non-target effects of T. aripo introduction into southern Africa has significantly advanced classical biological control efforts against an economically important cassava pest

New phytoseiid mites (Acari: Phytoseiidae) from tropical Africa

G.J. De Moraes, A.R. Oliveira, I.D. Zannou (2001): New phytoseiid mites (Acari: Phytoseiidae) from tropical Africa. Zootaxa 8: 1-10, DOI: http://doi.org/10.5281/zenodo.461648

Cannibalism and interspecific predation in a phytoseiid predator guild from cassava fields in Africa: evidence from the laboratory

Interspecific predation and cannibalism are common types of interaction in phytoseiid predator guilds, but the extent and nature of these interactions have not been determined yet in phytoseiid guilds composed of African native and neotropical exotic phytoseiid predators found in cassava habitat in southern Africa. We determined in laboratory experiments the level of cannibalism and interspecific predation among the three phytoseiid mite species Euseius fustis, Iphiseius degenerans, and Typhlodromalus aripo in the absence of food and in the presence of limited or abundant quantities of two food types – Mononychellus tanajoa and maize pollen – commonly found on cassava in Africa. When confined without food, only two T. aripo females laid each two eggs within 5 days, and this species survived longer than I. degenerans and E. fustis. In the presence of con- or hetero-specific larvae or protonymphs, the three species fed more on the former than on the latter, and more on hetero-specifics than on con-specifics. Oviposition rates of the three species did not exceed 0.7 egg/female/day on con- and hetero-specific immatures. Typhlodromalus aripo and E. fustis survived longer on con-specific and hetero-specific larvae and on hetero-specific protonymphs than in the absence of any food, while T. aripo survived longer than the two other species on the same diets. Provision of limited quantity of food decreased interspecific predation rate by I. degenerans and T. aripo, but not by E. fustis, and increased oviposition rate and longevity of all three species. Provision of abundant food, however, eliminated cannibalism by all three species and further reduced interspecific predation rates, but their oviposition and longevity remained relatively unchanged compared with limited food provision. Potential consequences of cannibalism and interspecific predation among phytoseiid mites on cassava for the biological control of M. tanajoa are discussed

Phytoseiid mites of the subtribes Typhlodromalina and Euseiina (Acari: Phytoseiidae: Euseiini) from subSaharan Africa

Twenty-four phytoseiid species of the subtribe Typhlodromalina Chant & McMurtry are reported in this paper. They refer to all species of this subtribe now known to occur in sub-Saharan Africa, and they belong to the general Amblydromalus Chant & McMurtry (5 species), Prasadromalus Chant & McMurtry (1 species), Typhlodromalus Muma (7 species) and Ueckermannseius Chant & McMurtry (11 species). Ten of these species are described for the first time and 11 species are redescribed. All of these were collected in cassava habitat, in an effort to determine the mites of that agro-ecosystem in that region. Redescriptions are based mostly on specimens collected in this study; for 6 species, redescriptions are also based on type specimens. A key to help in the separation of Typhlodromalina presently known to occur in sub-Saharan Africa is included. The morphological relation between a group of sub-Saharan species of Euseius (2 of which first described in this paper) and Ueckermannseius is also discussed

Phytoseiid mites of the subtribe Amblyseiina (Acari: Phytoseiidae: Amblyseiini) from sub-Saharan Africa

This is the fifth publication in a series to determine the phytoseiid mites of sub-Saharan Africa. Thirty-one phytoseiid species of the subtribe Amblyseiina are reported in this paper. They refer to all species of this subtribe known to occur in sub-Saharan Africa. Ten of these species are described for the first time, 15 species are redescribed and 6 are not evaluated in this study. Most of those species were collected in cassava habitat in tropical Africa and in other habitats in South Africa. A key is included to help in the separation of these species

Phytoseiid mites of the subfamily Phytoseiinae (Acari: Phytoseiidae) from sub-Saharan Africa

This is the seventh publication in a series concerning the phytoseiid mites of sub-Saharan Africa. Sixteen phytoseiid species of the subfamily Phytoseiinae (Chantia: 1 species, Phytoseius: 13 species and Platyseiella: 2 species) are reported in this paper. They include all species of this subfamily known to occur in sub-Saharan Africa. Ten of these species are redescribed. Most of those species were collected in cassava habitats in tropical Africa and in other habitats in South Africa. A key is included to help in the separation of these species

Species of the subtribes Arrenoseiina and Proprioseiopsina (Tribe Amblyseiini) and the tribe Typhloromipsini (Acari: Phytoseiidae) from sub-Saharan Africa

This is the fourth publication of a series to determine the phytoseiid mites of sub-Saharan Africa. Twenty-six phytoseiid species of the subtribes Arrenoseiina Chant & McMurtry (5 species) and Proprioseiopsina Chant & McMurtry (9 species), and tribe Typhlodromipsini Chant & McMurtry (12 species), are reported in this paper. They refer to all species of these taxa known to occur in sub-Saharan Africa. Eight of these species are described for the first time, 14 species are redescribed and 4 are not evaluated in this study. Most of those species were collected in cassava habitat in tropical Africa and in other habitats in South Africa. Keys are included to help in the separation of the species in each tribe or subtribe

Phytoseiid mites of the tribe Typhlodromini (Acari: Phytoseiidae) from subSaharan Africa

This is the ninth publication in a series on the taxonomy of phytoseiid mites of sub-Saharan Africa. Sixty-five phytoseiidspecies of the tribe Typhlodromini Wainstein, all of which are in the genus Typhlodromus Scheuten are reported in this paper (62 in the subgenus Anthoseius DeLeon and 3 in the subgenus Typhlodromus Scheuten). They refer to all species of this tribe known to occur in sub-Saharan Africa. Fifteen new species are described and 41 species are redescribed. Most of the reported species were collected in various habitats in southern Africa and in cassava habitats in tropical Africa. A key is included for the separation of these species