Carbohydrates and genetic factors influence cell division in citrus fruits from ovule cultures. Here, we investigated the effects of various carbohydrate sources (sorbitol, maltose, galactose, and lactose) on cell proliferation, somatic embryogenesis, and plant regeneration in three Citrus unshiu cultivars (‘Miyagawa wase’ [MW], ‘Haryejosaeng’ [HW], and ‘Nankan 20 gou’ [NW]), and one C. reticulata cultivar (‘Ootaponkan’ [PM]). In PM, carbohydrate sources did not affect proliferation; MW showed a significant but marginal increase in media containing 300 mM mannitol. It also proliferated well in media supplemented with 300 mM sorbitol and a mixture of galactose and lactose. NW achieved the best rate with 100 mM mannitol and 146 mM lactose, whereas HW proliferated well with 100 mM mannitol alone. Phylogenetic analysis using 18 citrus varieties showed distinct genetic differences among the cultivars, suggesting that the differences in regeneration capacities in different carbohydrate sources could be attributed to their genetic differences. This study provides valuable insights for optimizing tissue culture protocols for mandarin varieties and may enhance the efficiency of citrus breeding and tissue culture applications.