Chilli-based repellents have shown promise as deterrents against crop-raiding elephants in Africa. The authors experimented with ropes coated with chilli-based repellent as a cheap alternative to existing elephant crop raid deterrent methods in India.
Links:
[1] http://admin.indiaenvironmentportal.org.in/feature-article/testing-efficacy-chillitobacco-rope-fence-deterrent-against-crop-raiding-elephants
[2] http://admin.indiaenvironmentportal.org.in/category/author/k-chelliah
[3] http://admin.indiaenvironmentportal.org.in/category/author/g-kannan
[4] http://admin.indiaenvironmentportal.org.in/category/author/s-kundu-et-al
[5] http://admin.indiaenvironmentportal.org.in/category/journal/current-science
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/elephant
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/wildlife
[8] http://admin.indiaenvironmentportal.org.in/category/thesaurus/agriculture
[9] http://admin.indiaenvironmentportal.org.in/category/thesaurus/people-animal-conflicts
[10] http://admin.indiaenvironmentportal.org.in/category/thesaurus/buxa-np
[11] http://admin.indiaenvironmentportal.org.in/category/thesaurus/wynad-sa
[12] http://admin.indiaenvironmentportal.org.in/category/thesaurus/tamil-nadu
[13] http://admin.indiaenvironmentportal.org.in/category/thesaurus/west-bengal
[14] http://admin.indiaenvironmentportal.org.in/category/thesaurus/kerala