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1419ReseaRch T he inbred-hybrid method for producing hybrids was proposed at the turn of the 20th century and is the predominant method for producing hybrids today. Inbred lines are established with varying degrees of homozygosity depending on the extent of inbreeding depression seen in a particular species ( Jones and Bingham, 1995;Havey, 1999;Janick, 1999;Miranda Filho, 1999). Complementary inbred lines are then crossed together to create hybrid progeny, which are valued for their vigor and uniformity. The discovery of CMS and effective nuclear restorer genes led breeders to seek efficient hybrid production in table beet (Beta vulgaris L.) and carrot (Daucus carota L.).