About the invasive insects and their biological management

1. Cassava Green Mite
A case study for Classical Biological Control
Jawwad Hassan Mirza
Ph.D. Scholar (ID# 435108485)
Acarology Laboratory
Department of Plant Protection
King Saud University, AlRiyadh, KSA

2. Cassava
Manihot esculenta (Crantz)
• Family: Euphorbiaceae
• Native to South America, Exotic to
Africa (16th Centuray)
• Staple food for 200 million people
• Tubers and leaves consumed
• Low input, easy grow, survives poor soil and
harsh environment, famine reserve crop
• Among major pests = Cassava Green Mite

3. Cassava Green Mite
Mononychellus tanajoa (Bondar)
(Acari: Tetranychidae)
• Native to USA, invasive to
Africa (1970)
• Invaded Uganda, 1971
• Spread to 27 Countries, 1985
• Reduction of 50% leaf weight, 80% tuber yield
• Introduced accidently
(Nyiira, 1972; Bellotti et al. 1999; Pallangyo et al. 2004)

4. DAMAGE SYMPTOMS

5. CASSAVA
REGIONS
PATHWAY FOR
INVASION
Lu et al. 2012

6. DISTRIBUTION AND INVASION
Lu et al. 2012

7. DISTRIBUTION IN AFRICA
Lu et al. 2012

8. WHY AFRICA?
• Lack of Acarologists
• Established host on large scale
• Absence of Bio-control agents
• Lack of Co-Evolution between predator and
prey

9. IMPORTANCE OF CASSAVA

10. FAOSTAT, 2012

11. FAOSTAT, 2012

12. FAOSTAT, 2012

13. OBJECTIVE
Keeping in view the importance of Cassava plant and economic
state of local farmers, the objective was:
Develop an efficient management strategy that
can keep the pest population under check and
is cost effective

14. HISTORY OF MANAGEMENT
• Cultural control didn’t give desired results solely
• Host plant resistance was a slow process
• Acaricides caused environmental, health issues and
pest resistance
• Biological Control was the best option
 Classical Biological Control
Costa et al. 2012

15. CLASSICAL BIOLOGICAL CONTROL
• International Institute of Tropical Agriculture
(IITA), 1980
• Introduced different bio-control agents including
fungi, insects and Mites
• Phytoseiid Mites
• 1984: 5.2 million Phytoseiids (7 species) from
Colombia = none adapted
• 1988: 5.3 million Phytoseiids from Brazil = success
– (Tryphlodromalus spp, Neoseiulus spp)
Yaninek et al. 1993

16. CLASSICAL BIOLOGICAL CONTROL
• 5 species of Typhlodromalus = T. aripo
• Introduced in Benin, 1993
• Spread to 21 countries
• In prey absence = dispersed or stayed on plant
• Reduced pest to 90%
• Increase in yield 35% in one season
• Add up $60 million/season
Onzo et al. 2005

17. OTHER BIO-AGENTS
• Among the Exotic and Indigenous Bio-agents
• Tryphlodromalus manihoti has high predation
• Euseius fustis & T. manihoti = intraguild predation
• T. aripo & T. manihoti = successful results
• Neoseiulus idaeus:
– 32% pest control
– Survives low pest density
• Euseius fustis:
– Can remain on artificial diet
– Best performs when used solely
(Onzo et al. 2003)

18. TAKE HOME MESSAGE
• Quarantine measures should be strictly
followed
• Conservation of biological control agents
• Artificial diet ensures the conservation

19. REFERENCES
• Bellotti, A.C., Smith, L. and Lapointe, S.L., 1999. Recent advances in cassava pest management. Ann. Rev.
Entomol. 44: 343-370.
• Costa, E.C., Teodoro, A.V., Re go, A.S., Maciel, A.G., and Sarmento, R.A., 2012. Population structure and
dynamics of the cassava green mite Mononychellus tanajoa (Bondar) and the predator Euseius ho
(DeLeon) (Acari: Tetranychidae, Phytoseiidae). Arthropods. 1: 55-62.
• Lu, H., Ma, Q., Chen, Q., Lu, F., and Xu, X., 2012. Potential geographic distribution of the cassava green
mite Mononychellus tanajoa in Hainan, China. African Journal of Agricultural Research. 7: 1206-1213.
• Nyiira, Z.M., 1972. Report on investigation of cassava mite, Mononychus tanajoa Bondar. Unpublished
report. Kampala, Uganda: Kawanda Research Station.
• Onzo, A., Hanna R. and Sabelis M.W., 2005. Biological control of cassava green mites in Africa: impact of
the predatory mite Typhlodromalus aripo. Entomologische Berichten. 65(1).
• Onzo, A., Hanna, R. and Sabelis, M.W., 2003. Interactions in an acarine predator guild: impact on
Typhlodromalus aripo abundance and biological control of cassava green mite in Africa. Exp. Appl. Acarol.
31: 225–241.
• Pallangyo, B., Hanna R., Toko M., Gnanvossou D., Mgoo V., Otema M., Onzo A., Hountondji F., Nsami E. and
Mfugale O., 2004. Biological control of cassava green mite in Tanzania. Proceedings of 9th Triennial
Symposium of the International Society for Tropical Root Crops - Africa Branch (ISTRC - AB) Mombasa,
Kenya.
• van Rijn, P.C.J. and Tanigoshi, L.K., 1999. Pollen as food for the predatory mites Iphiseius degenerans and
Neoseiulus cucumeris (Acari: Phytoseiidae): dietary range and life history. Exp. Appl. Acarol. 23: 785–802.
• Yaninek, J.S., A. Onzo and B. Ojo, 1993. Continent wide experiences releasing neotropical phytoseiids
against the exotic cassava green mite in Africa. Exp. Appl. Acaro. 16: 145-160.

20. THANK YOU FOR YOUR
TIME
Pic: A Spider Mite (Tetranychus urticae) infestation on Marygold