Selenium biofortification on garlic growth and other nutrients accumulation

ABSTRACT Selenium (Se) is an essential element for humans and has anti-cancer function. Garlic can accumulate Se, so it is an option to Se supplementation in the human diet. The aim of this research was to study Se uptake and accumulation during garlic growth. Four doses of Na2SeO4 and Na2SeO3 solution were applied in the substrate (0, 5, 10 and 15 kg ha-1 Se) for one time in August 2014, with a random plot design and 3 replicates on garlic clone Rubi INTA. Three harvests were made, in September, October and December 2014. After each harvest, leaves, bulbs and roots were separated and conditioned (peeled and chopped), lyophilized, and finally acid-digested prior to Se, Mg, Zn, Mn, Cu, Fe, P and S determination by inductively coupled plasma mass spectrometry (ICP-MS). The Se accumulation was proportional to Se doses and did not affect garlic growth. Also, Se distribution among different organs was related to the garlic growth cycle. The Se presence decreased accumulation of Mg, Mn, Cu, Fe, P and S but increased Zn accumulation in plants. Garlic can be an important Se source to humans but it is important to consider Se-doses for biofortification.

摘要：硒（Se）是人体必需的微量元素，具备抗癌功效。大蒜可富集硒元素，因此可作为人类膳食中硒补充的备选来源。本研究旨在探究大蒜生长过程中的硒吸收与富集规律。试验于2014年8月向栽培基质单次施加四种浓度的硒酸钠（Na₂SeO₄）与亚硒酸钠（Na₂SeO₃）溶液，施硒剂量分别为0、5、10、15 kg·ha⁻¹（以Se计），采用随机区组设计，以大蒜无性系Rubi INTA为材料，设置3次重复。分别于2014年9月、10月和12月进行三次采收。每次采收后，分离大蒜的叶片、鳞茎与根系，经去皮、切碎预处理后进行冷冻干燥，最后经酸消解，采用电感耦合等离子体质谱法（inductively coupled plasma mass spectrometry，ICP-MS）测定样品中硒、镁、锌、锰、铜、铁、磷及硫的含量。结果表明，大蒜的硒富集量与施硒剂量呈正相关，且施硒未对大蒜生长产生影响；此外，硒在不同器官中的分布与大蒜生长周期密切相关。植株体内硒的存在会降低镁、锰、铜、铁、磷与硫的富集水平，但可提升锌的积累量。大蒜可成为人类重要的硒膳食来源，但在开展硒生物强化栽培时，需合理考量施硒剂量。