GROWTH AND YIELD OF THREE SUNFLOWER HYBRIDS CULTIVATED FOR TWO YEARS UNDER MEDITERRANEAN CONDITIONS

Abstract

Sunflower (Helianthus annuus L.) is globally one of the most important oil crops, lately expanding in more semi-arid Mediterranean regions. A 2-years field study was conducted to evaluate growth, grain and oil productivity of three sunflower hybrids (PR64E83, Oleko and PR63A90). Plant height, number of green leaves, weight of 1000-grains and grain number were significantly affected by the interaction of year and sunflower hybrid. Grain yield resulted to differences ranged among 13 and 34 % between the two years. In 2009, Oleko and PR63A90 were the most productive hybrids regarding seed (8210 and 7500 kg/ha, respectively) and oil (2960 and 2950 kg ha-1, respectively), while PR63A90 was the significantly more productive hybrid during the second year (2010). Hybrids such as Oleko seem ideal for high grain and oil yield (with a high concentration of monounsaturated fatty acids); however they fit better to a crop rotation, probably due to a high phytotoxicity of their residues which reduces the yield of the second year. On the contrary, the ability of some non high-oleic hybrids such as PR63A90 to keep high grain yield even in the second year of their cultivation in the same field is clearly a very desirable trait and it should be further tested, since it can result to very high oil yield.