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The development of organic agriculture in France was steady since 2010 but became stronger since 2014. Like other crops, the cultivated areas of organic soybean and sunflower doubled from 2014 to 2018. With a view to better characterize cultural practices in organic production, Terres Inovia and ITAB (in collaboration with Agence Bio) conducted in 2016 and 2017 a national farmers’ survey. These surveys reveal that sunflower was mainly cultivated over the same types of soil than in conventional production but were integrated in more diversified rotations. The main differences between organic and conventional systems concern sowing date and weed control. Organic sunflower was sown very lately compared to conventional one, which impacted the yield severely. Weed were controlled through ploughing, mechanical weeding and crop rotation and weed control was judged as satisfying by a major part of producers. Concerning soybean, a great difference is the use of irrigation which is almost systematic in conventional but concerned only 50% of cultivated area in organic production. Contrary to sunflower, soybean is integrated in short crop rotation, particularly when it was irrigated. This demonstrated the high profitability of soybean in organic systems. Like for sunflower, weed control done through ploughing, mechanical weeding, and crop rotation and weed control was also judged satisfying; nevertheless, criteria on harvest impurities are more severe and to respect them, organic farmers also use hand weeding in complement. These surveys will be reconducted over the years to be able to follow the changes of cultural practices over the years.

Weedy sunflowers have been officially reported in South-Western France in 2004. They display a combination of phenotypic traits of the wild and domesticated forms of the species and infest between 15 and 20% of fields of sunflower crop in this area, although at variable levels. When the infestation is strong, it affects seed yield and oil quality. Molecular studies showed that weedy sunflowers most probably resulted from accidental crop-wild hybridization during the seed production process and from the introduction of the resulting hybrids into commercial seed lots. Multiple independent introductions were at the source of the number of infested fields observed nowadays. The temporal dynamics of the infestation of a field and the detailed conditions for its success remain largely unknown. The flowering synchrony between crops and weeds is substantial, even if a variable fraction of the weeds (15-55%) flower completely outside the crop flowering period. Molecular survey of adult weedy plants and their progenies showed that crop-toweed gene flow occurs, at a rate that can reach 35 %on average, at the peak of the crop flowering period. We draw perspectives on the durability of herbicide-tolerant sunflower varieties as a solution to control these weeds, and call for more studies tackling weed management from an evolutionary lens.

Soybean is cultivated in Europe as a GM free cultivation. In spite of a growing demand in identity preserved (IP) seeds and of the high environmental benefit of the soybean in the crop rotations,a great decrease of the soybean acreage has been observed in France and in Europe since 2002. That’s why in 2007, Cetiom and Onidol, two bodies of the French oilseed crop organisation decided to carry out a comprehensive survey on the different actors of the soybean production chain from the farmers until the feed and food soybean users. The study showed that 12% of the total acreage is planted under organic farming and that most surfaces are still grown under IP process. It also highlighted that the decrease of soybean’s surfaces till 2008 was mainly due to an insufficient economic competitiveness compared to other crops. The survey proved that the French production gained market shares between 2002 and 2007 for the soyfood industry supply (from 5 to 25% of the total acreage). The remaining production is processed in small or medium extrusion plants for the local animal raising. The needs of the industry were described in details showing that the main asset of the French production is the good control of the whole production chain, the high quality management by the farmers, the good protein content and shorter logistic chains compared to the imported soybean. For the future, the increasing environmental constraints and the larger demand of European soyfood industry but also of local high-quality feed and animal raising could lead soybean to recover between 100 000 and 150 000 hectares in France.

This paper presents the main research works and search results which have been discussed inside the 17th international sunflower conference, held in Cordoba (June 8-12, 2008) and organised by the International sunflower association (ISA). It focusses on five main topics: Breeding and genetics, Pathology, Crop production and physiology, Oil and meal quality, Sunflower production in the world and in Spain.

The 16th International Sunflower Conference was held from August 29th to September 2th, 2004 in Fargo, North Dakota, USA. 250 participants were present and 25 countries were represented. The leaders of the world’s main research programs on sunflower were in Fargo. Consequently, it is possible to sum up the principal orientations of world research on sunflower at present. Concerning disease resistance and pathology, downy mildew and sclerotinia are the main studied topics. Only few studies are carried out on other diseases. The main subject treated in weed control is the selection and efficiency of sunflower varieties with resistance to imidazoline herbicides, to control broomrape and other weeds. For crop production and physiology, the main programs are leaded by Argentina (interesting study about productivity and high densities) and France (Heliotest: a decision support system for nitrogen fertilization). Concerning breeding and genetics, a lot of studies were presented and confirmed a great improvement in the characterization of the genome of sunflower and other compositae. The helianthus wild species germplasm collection which is held in Ames (Iowa) was presented and described. Concerning oil composition, tocopherols and high oleic appeared as the main topics.