The effect of temperature, humidity and photoperiod on the development of Neozygites cf. floridana (Weiser and Muma) in the cassava green mite, Mononychellus tanajoa (Bondar) was studied in the laboratory. Dead infected mites began to appear 2.5 days after inoculation. At 33 and 28°C peak mortalities were higher and occurred earlier (after 2.5 days), than at 23 and 18 ° C. Mean LTs0 (time for half the infected mites to die) decreased with increasing temperature as follows: 3.9, 3.0, 2.9 and 2.5 days at 18, 23, 28 and 33 ° C, respectively. When placed under conditions of high relative humidity for a period of 24 h, the percentage of dead infected mites from which the fungus sporulated was highest at 28 ° C (51.4%) and lowest at 33 ° C (6.5%). The development of the fungus inside the mite was not significantly affected by ambient humidity or photoperiod. No significant interactions between tested factors were found.

This datasheet on Mononychellus tanajoa covers Identity, Overview, Distribution, Dispersal, Hosts/Species Affected, Diagnosis, Biology & Ecology, Environmental Requirements, Natural Enemies, Impacts, Uses, Prevention/Control, Further Information.

The cassava green mite, M. tanajoa, is of Neotropical origin but was accidentally introduced to Africa in 1971 (Nyiira, 1972). By 1985, the pest had spread throughout the cassava belt of Africa (Yaninek and Heren, 1988). M. tanajoa affects the important annual crop cassava (Manihot esculenta) and can cause a reduction of about 50% in leaf weight, and up to 80% tuber yield loss (Shukla, 1976; Gutierrez et al., 1988; Pallangyo et al., 2004). M. tanajoa is mainly dispersed by human activity, whereby infested plant materials and contaminated media are transported over long distances. Natural dispersion by wind and water may also spread the cassava green mite. In areas where both the pest and host plant are exotic, there is no evidence that indigenous natural enemies are significant factors in limiting the mite population growth rates. M. tanajoa can feed and reproduce on other plant species (Moraes et al., 1995) and is reported as a quarantine pest (Delalibera et al., 1992; EPPO, 2009).