SYNTHESIS OF STORAGE RESERVES IN DEVELOPING SEEDS OF SUNFLOWER

The patterns of synthesis and accumulation of storage compounds were c ompared in young developing embryos of sunflower. Oil biosynthesis was clearly initiated very early in development with total lipids account ing for about 18% of the dry weight at the earliest stage studied. Thi s was associated with the accumulation of oleosins and the expression of cytochrome b(5). In contrast, significant amounts of helianthinin ( 11S globulin) and 2S albumin were only observed in stages 3 and 4; res pectively. The early expression of oleosins contrasts with previous st udies of other oilseeds and is consistent with the hypothesis that the y are intimately associated with the biogenesis of oil bodies. (C) 199 8 Elsevier Science Ltd. All rights reserved.