They need less water, no fertilizer and hardly any care or attention.
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/local-seeds-best-bet-against-climate-change
[2] http://admin.indiaenvironmentportal.org.in/category/newspaper/hindu-chennai
[3] http://admin.indiaenvironmentportal.org.in/category/thesaurus/climate-change
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/farmers
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/seeds
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/kerala
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/karnataka
[8] http://admin.indiaenvironmentportal.org.in/category/thesaurus/orissa
[9] http://admin.indiaenvironmentportal.org.in/category/thesaurus/west-bengal
[10] http://admin.indiaenvironmentportal.org.in/category/thesaurus/rice
[11] http://admin.indiaenvironmentportal.org.in/category/thesaurus/dindigul-d
[12] http://admin.indiaenvironmentportal.org.in/category/thesaurus/traditional-knowledge