ADAPTABILITY OF IMPROVED RICE VARIETIES IN SENEGAL

Using yield gap and adaptability (modified stability) analyses, this s tudy evaluated the potential relevance of improved rice varieties rele ased by, or soon to be released by, the Senegalese Agricultural Resear ch Institute (ISRA) in the Casamance Region of Senegal. Results from r esearcher-managed, on-farm trials indicated that level of fertilizer a pplied accounted for most of the difference in Yield Gap II (i.e. the difference between potential [experimental] and actual yields at the f arm level), followed by variety. Also, the adaptability analysis resul ts indicated that most of the improved varieties performed poorer than local varieties under poor production environments but better than lo cal varieties under good production environments. We concluded that th e rice breeding programme needs to pay greater attention to developing varieties better adapted to the varied production environments under which farmers operate. (C) 1998 Elsevier Science Ltd. All rights reser ved.