In West Africa two rice species (Oryza glaberrima Steud. and Oryza sativa L.) co-exist. Although originally it was thought that interspecific hybridization is impossible without biotechnological methods, progenies of hybridization appear to occur in farmer fields.
Links:
[1] http://admin.indiaenvironmentportal.org.in/feature-article/evidence-emergence-new-rice-types-interspecific-hybrid-origin-west-african-farmers
[2] http://admin.indiaenvironmentportal.org.in/category/author/edwin-nuijten
[3] http://admin.indiaenvironmentportal.org.in/category/author/robbert-van-treuren
[4] http://admin.indiaenvironmentportal.org.in/category/author/paul-c-struik-et-al
[5] http://admin.indiaenvironmentportal.org.in/category/journal/plos-one
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/agriculture
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/plant-breeding
[8] http://admin.indiaenvironmentportal.org.in/category/thesaurus/rice
[9] http://admin.indiaenvironmentportal.org.in/category/thesaurus/farmers
[10] http://admin.indiaenvironmentportal.org.in/category/thesaurus/africa
[11] http://admin.indiaenvironmentportal.org.in/category/thesaurus/gambia
[12] http://admin.indiaenvironmentportal.org.in/category/thesaurus/ghana
[13] http://admin.indiaenvironmentportal.org.in/category/thesaurus/senegal
[14] http://admin.indiaenvironmentportal.org.in/category/thesaurus/sierra-leone
[15] http://admin.indiaenvironmentportal.org.in/category/thesaurus/togo