According to experts, no seed variety is to be used continuously for more than a decade
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/single-variety-paddy-seeds-reason-pest-attacks-odisha-aikms
[2] http://admin.indiaenvironmentportal.org.in/category/newspaper/hindu-new-delhi
[3] http://admin.indiaenvironmentportal.org.in/category/thesaurus/orissa
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/rice
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/farmers
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/chemical-fertilisers
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/agriculture