442
8 Conclusion
The use of O. longinoda in managing cashew and other crop pests is currently the
best and most sustainable alternative to insecticide-based pest management strategies in Tanzania, particularly in orchard trees, as the differences between using recommended insecticides and weaver ants were not statistically significant (P < 0.001).
Moreover, using O. longinoda fits well with organic farming providing a reliable
solution to the attempt by the world authorities to minimize pollution and protect
human beings and the environment from agricultural produce with pesticide residues. The technology has been proven economically feasible by all analytical methods such that the benefits accrued from its use are invaluable. When partial budgeting
method was used, the net change in benefit ranged from US$4.85 to US$7.72 per
tree by switching from conventional insecticide (Karate) to O. longinoda, while
switching from no control to using O. longinoda led to net change in benefit from
US$5.55 to US$9.23 per tree. The marginal rate of return indicated net benefit of up
to US$11.39 per tree when O. longinoda was used, compared to US$5.74 per tree
when Karate
®
was used. Thus, the use of O. longinoda against cashew pests does
not only protect crops and add economic gains from investments in production; it
also ensures protection of farmers’ health and the environment. It is an undeniable
fact that O. longinoda technology will reduce the production costs, offer sustainable
solution to cashew pests and open ways to markets that requires high-quality agricultural produce with no pesticide residuals.
Acknowledgement Authors are thankful to Dr. Joachim Offenberg and Prof. Mogen G. Nielsen
of Aarhus University, Denmark, for technical collaboration in designing the research work. The
study was financially supported by the Danish International Development Assistance (DANIDA)
through grant DFC no. 10-025AU.
References
Abdulla NR (2016) Weaver ant, Oecophylla longinoda Latreille (Hymenoptera: Formicidae) as
biocontrol agent on major insect pests of cashew and mango in Tanzania. PhD thesis, 206+i–
xiv pp
Abdulla NR, Rwegasira GM, Jensen K-MV, Mwatawala MW, Offenberg J (2016) Potential of
Oecophylla longinoda Latreille (Hymenoptera: Formicidae) in managing major insect pests
in organic cashew production systems. J Int Soc Org Agric Res. https://doi.org/10.1007/
s13165-016-0152-8
Adandonon A, Vayssieres J-F, Sinzogan A, Van Mele P (2009) Density of pheromone sources of
the weaver ant Oecophylla longinoda affects oviposition behaviour and damage by mango fruit
flies (Diptera: Tephritidae). Int J Pest Manag 55(4):285–292
Agboton BV, Salifu D, Segumi Z, Sijaona ME, Shomari S, Ekesi S, Maniania NK (2013)
Bioecology of some key cashew insect pests and diseases in diverse habitats and landscapes in
Tanzania. J Appl Entomol 137:782–789
Anato FM, Wargui RB, Sinzogan AAC, Offenberg J, Adandonon A, Vayssières JF, Kossou DK
(2015) Reducing losses inflicted by insect pests on cashew, using weaver ants as a biological
control agent. Agric For Entomol 17:285–291
G. M. Rwegasira et al.
8 Conclusion
The use of O. longinoda in managing cashew and other crop pests is currently the
best and most sustainable alternative to insecticide-based pest management strategies in Tanzania, particularly in orchard trees, as the differences between using recommended insecticides and weaver ants were not statistically significant (P < 0.001).
Moreover, using O. longinoda fits well with organic farming providing a reliable
solution to the attempt by the world authorities to minimize pollution and protect
human beings and the environment from agricultural produce with pesticide residues. The technology has been proven economically feasible by all analytical methods such that the benefits accrued from its use are invaluable. When partial budgeting
method was used, the net change in benefit ranged from US$4.85 to US$7.72 per
tree by switching from conventional insecticide (Karate) to O. longinoda, while
switching from no control to using O. longinoda led to net change in benefit from
US$5.55 to US$9.23 per tree. The marginal rate of return indicated net benefit of up
to US$11.39 per tree when O. longinoda was used, compared to US$5.74 per tree
when Karate
®
was used. Thus, the use of O. longinoda against cashew pests does
not only protect crops and add economic gains from investments in production; it
also ensures protection of farmers’ health and the environment. It is an undeniable
fact that O. longinoda technology will reduce the production costs, offer sustainable
solution to cashew pests and open ways to markets that requires high-quality agricultural produce with no pesticide residuals.
Acknowledgement Authors are thankful to Dr. Joachim Offenberg and Prof. Mogen G. Nielsen
of Aarhus University, Denmark, for technical collaboration in designing the research work. The
study was financially supported by the Danish International Development Assistance (DANIDA)
through grant DFC no. 10-025AU.
References
Abdulla NR (2016) Weaver ant, Oecophylla longinoda Latreille (Hymenoptera: Formicidae) as
biocontrol agent on major insect pests of cashew and mango in Tanzania. PhD thesis, 206+i–
xiv pp
Abdulla NR, Rwegasira GM, Jensen K-MV, Mwatawala MW, Offenberg J (2016) Potential of
Oecophylla longinoda Latreille (Hymenoptera: Formicidae) in managing major insect pests
in organic cashew production systems. J Int Soc Org Agric Res. https://doi.org/10.1007/
s13165-016-0152-8
Adandonon A, Vayssieres J-F, Sinzogan A, Van Mele P (2009) Density of pheromone sources of
the weaver ant Oecophylla longinoda affects oviposition behaviour and damage by mango fruit
flies (Diptera: Tephritidae). Int J Pest Manag 55(4):285–292
Agboton BV, Salifu D, Segumi Z, Sijaona ME, Shomari S, Ekesi S, Maniania NK (2013)
Bioecology of some key cashew insect pests and diseases in diverse habitats and landscapes in
Tanzania. J Appl Entomol 137:782–789
Anato FM, Wargui RB, Sinzogan AAC, Offenberg J, Adandonon A, Vayssières JF, Kossou DK
(2015) Reducing losses inflicted by insect pests on cashew, using weaver ants as a biological
control agent. Agric For Entomol 17:285–291
G. M. Rwegasira et al.