Abstract: A field experiment was conducted to evaluate the effect of zinc (Zn) fertilization on Zn accumulation in garlic plants. The experiment was designed as five zinc treatment groups and one control, and Zn was added as base fertilizer. The results showed that the Zn mass fractions in garlic leaves, young garlic shoots and the bulbs were significantly increased up to 935, 718 and 964 mg/kg (dry weight) respectively. The Zn forms in different edible garlic organs all changed after the addition of Zn fertilizers. Furthermore, the proportions of free Zn ions were improved in garlic leaves, young garlic shoots and bulbs with the increase of Zn levels, while the proportions of water-extractable Zn and residual Zn decreased. However, the proportion of salt- and alkali-extractable Zn increased in garlic leaves and young garlic shoots, but decreased in the bulbs. The in vitro simulation of gastrointestinal digestion showed that the Zn dissolution rate in Zn-fortified bulbs increased by 68% compared to the control. When mixing together with rice, the Zn dissolution rate of garlic bulbs increased by 2.6 times, which indicates that the nutritional quality of Zn improved significantly via bio-fortification.

Key words: garlic, Zn bio-fortification, occurrence state, nutritional quality