The essential role of seeds in crop establishment and improvement has long been recognized. Poor emergence in the fields is one of the main factors responsible for low yields in sugar beet. In order to investigate the effects of size, pelleting and coating of nine seed lots of sugar beet (Beta vulgaris) on the germination, an experiment was conducted under laboratory conditions, based on completely randomized design with 4 replications of 25 seeds. Top of Paper (TP) was used to conduct the experiment. Seeds were first divided into two sizes, small and large, by observation. Then, seed pellets removed on the seed lots that had low germination before conducting the germination test. Finally, seed coat removed before conducting the experiment. Germination (radicle emergence ≥2 mm) was counted daily for 15 days to calculate mean germination time (MGT). Final germination percentage was recorded. The number of normal seedlings and seedlings length were assessed on the final day. The results indicated that increased MGT resulted decreasing the normal seedling percentages, final germination and seedlings length. Small seeds had a higher final germination percentage, normal seedlings and seedlings length but with lower MGT, compared to large seeds. Final physiological germination and normal seedlings of removed seed coating lots were over 70% and 40%, respectively. Final physiological germination and normal seedlings of removed seed pelleting lots were over 40% and 30%, respectively. Therefore, removing the pelleting and coating of seeds enhanced the germination and normal seedlings percentages. It seems that unsuitable pellets have a physical force that prevents imbibition and radicle protrusion.

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