Resistance of the predacious mite, euseius kenyae (acari: phytoseiidae) to chlorpyrifos (dursban ®) in kenyan coffee farms
AbstractThis study was carried out to assess whether the predacious phytoseiid mite, Euseius kenyae (Swirski and Ragusa), commonly found in major coffee growing regions in Kenya has developed resistance to Chlorpyrifos. Mite populations were collected from coffee farms harbouring E. kenyae and where Chlorpyrifos or other organophosphates were sprayed to manage the primary coffee insect pests. The mites collected were reared in mass in the laboratory for bioassays. The findings showed that under coffee agro-ecosystems, levels of resistance existed among the populations of E. kenyae after their exposure to Chlorpyrifos or other organophosphates. The population of E. kenyae from a coffee farm (C44) was most susceptible to Chlorpyrifos with LC50 = 0.044 that was below the lowest concentration of 0.1875 ml per litre of water which was tested. The E. kenyae from coffee farms (C1, C4, C7, C37, C25 and C119) had resistance ratios more than ten times that of C44. The coffee farms (C2, C12, C19, C116, C31, C50 and C72) had populations of E. kenyae susceptible to Chlorpyrifos at concentration of 0.75 ml per litre of water which is the field recommended rate for control of insect pests in coffee. The population of E. kenyae from C7 was resistant to the highest field rate of 200% (1.5 ml per litre of water) with LC50 of 1.716 and resistance ratio of 39 times. The existence of resistance populations of E. kenyae is an aspect that needs to be considered in the integrated pest control strategies against coffee insect pests.
Open access articles published in the Journal of Agriculture, Science and Technology are under the terms of the Creative Commons Attribution (CC BY) License which permits use, distribution and reproduction in any medium, provided the original work is properly cited. The CC BY license permits commercial and non-commercial re-use of an open-access article, as long as the author is properly attributed.
Copyright on any research article published in the Journal of Agriculture, Science and Technology is retained by the author(s). The authors grant the Journal of Agriculture, Science and Technology with a license to publish the article and identify itself as the original publisher. Authors also grant any third party the right to use the article freely as long as its original authors, citation details and publisher are identified.
Use of the article in whole or in part in any medium requires proper citation as follows:
Title of Article, Names of the Author, Year of Publication, Journal Title, Volume (Issue) and page. Links to the final article on the JSRE website are encouraged.
The Creative Commons Attribution License does not affect any other rights held by authors or third parties in the article, including without limitation the rights of privacy and publicity. Use of the article must not assert or imply, whether implicitly or explicitly, any connection with, endorsement or sponsorship of such use by the author, publisher or any other party associated with the article.
For any reuse or distribution, users must include the copyright notice and make clear to others that the article is made available under a Creative Commons Attribution license, linking to the relevant Creative Commons web page. Users may impose no restrictions on the use of the article other than those imposed by the Creative Commons Attribution license.
To the fullest extent permitted by applicable law, the article is made available as is and without representation or warranties of any kind whether express, implied, statutory or otherwise and including, without limitation, warranties of title, merchantability, fitness for a particular purpose, non-infringement, absence of defects, accuracy, or the presence or absence of errors.