Fig. 1
Hilum phenotypic differences between seeds of Clark isolines UC7 (ii R T Mi g) and UC413 (ii R t mi G) at three late developmental stages. Seeds in the left hand panels have normal size hilum (UC7) while the ones in the right (UC413) have the minute hilum phenotype and associated cracks in the seed coat. Seed coat cracks from the hilum and beyond are formed at a late stage of seed maturation and clearly seen in UC413 dry seed in the bottom right panel. The three stages of development shown to the right of the image are: full seed (R7), mid-desiccation (R7-R8) and dry seed (R8). The white oval lines around the hilum in the upper panels represent the area of the hilum and immediate seed coat region, designated the EH (extended hilum), dissected from seeds at the early maturation stages of EH10 (10–25 mg seed), EH25 (25–50 mg), and EH50 (50–100 mg) seed fresh weight developmental stages (not shown) . All genotypes are homozygous in the inbred isolines