30 years of sunflower breeding in France

Fourgroups of five varieties representing the French sunflower crop since 1965 were grown in 25 yield trials and 7 disease resistance trials in 2000 and 2001. These trials showed a mean increase of 40% in seed yield for the five varieties registered since 1995 over those registered in 1965-1975 (33 kg/ha or 1.3% per year), with an acceleration of gain in recent years. Oil yield increased by almost 50%; since 1980 as a result of seed yield increase as oil content has remained stable since this date. There was the same mean and range for earliness and plant height in 1970 and 2000, whereas lodging was reduced by 80%, Sclerotinia head rot attack by 60% and Phomopsis stem canker by 30%. Improvement in seed yield was due to improved seed number/m(2) in the period 1975-1985, but then to an increase in seed size. The increased disease resistance accounted for 25% of the increased seed yield of recent varieties in the yield trials, 7125 of which showed some Sclerotinia or Phomopsis attack. The best demonstration of yield improvement came from trials in Central France, sown early. Such conditions give the highest potential yields but also some risk of disease on older varieties. It is concluded that modern varieties would be well adapted to regions of high potential yield if economic conditions favoured the sunflower crop.