Oil and fatty acid distribution in different circles of sunflower head

Prevailing temperature at anthesis influences pollen health, fertilisation, seed filling, oil and fatty acid accumulation in different circles of sunflower head. Field experiments were conducted, during 2007 and 2008, at Pir Mehr Ali Shah, Arid Agriculture University, Rawalpindi, Pakistan, to document oil and fatty acid distributions in different circles of sunflower head. Hybrid S-278 was planted in randomised complete block design with a two factors factorial experiment, with four replications. At maturity, heads were divided into three equal circles (outer, middle and central); thereafter, oil and fatty acid distributions were separately determined in each circle. Oil and fatty acid concentrations in three circles differed significantly. The outer circle accumulated high oil and oleic contents which decreased to a minimum in the central circle; however, linoleic acid consistently increased, from outer to central circle, during both the years.