Improving Zn bioavailability in lentil through fertilization

加拿大是世界上最大的扁豆（Lens culinaris）生产国和出口国，萨斯喀彻温省是主要的扁豆生产省。加拿大小扁豆出口在发展中国家有很大的市场，在这些国家，由于在日常饮食中严重依赖缺乏营养的谷物和谷物豆类，缺锌是造成人类健康问题的主要原因。并非谷物中的所有锌都能被人体吸收，因为像植酸盐这样的抗营养物质会与锌结合，形成不溶性复合物，不能被人体吸收。对扁豆等豆类作物施锌可以提高粮食中锌的产量和浓度，有可能改善粮食的人体营养品质，增加加拿大扁豆的市场需求。然而，这增加“生物可利用”锌的程度是未知的。由于磷是植酸抗营养物的主要成分，锌和磷的施用都会影响小扁豆作为人体营养中的生物强化锌源的质量。植酸与锌的摩尔比已被用来划分食物中锌的生物利用度，并建立了模型来预测锌的吸收。在萨斯喀彻温省的一系列土壤中，小扁豆中锌的估算、其生物有效性以及与作物和土壤管理因素（如小扁豆类别、锌施肥方法和其他营养物质如磷）的关系被提出进行研究。具体而言，本研究考察了土壤和叶面施用锌肥对三种不同类型扁豆锌浓度和植酸含量的影响。锌吸收的三变量模型将用于估计锌在小扁豆籽粒中的生物利用度。以小扁豆为研究对象，研究了不同类型小扁豆对锌的再动员和分配，并对锌的施用进行了评价。

Canada is the largest producer and exporter of lentil (Lens culinaris) in the world, and Saskatchewan is the leading lentil producing province. A large market for Canadian lentil exports exists in developing countries where zinc (Zn) deficiencies are a leading cause of human health problems due to heavy reliance on nutrient deficient cereals and grain legumes in the daily diet. Not all of the Zn in grain is available to humans, due to binding of anti-nutrients like phytate to Zn to form insoluble complexes that cannot be absorbed by the human body. Fertilization of pulse crops like lentil with Zn can increase the yield and concentration of Zn in the grain and potentially improve the human nutritional qualities of the grain, and increase the market demand for Canadian lentils. However, the extent to which this increases "bioavailable" Zn is unknown. As phosphorus is a major component of the phytate anti-nutrient, both zinc and phosphorus fertilization may affect the quality of lentil as a biofortified source of Zn in human nutrition. The phytate to zinc molar ratio has been used to categorize the zinc bioavailability in food, and models have been developed to predict Zn absorption. Estimation of Zn in lentils, its bioavailabity and relationship to crop and soil management factors such as lentil class, Zn fertilization practices, and other nutrients such as phosphorus are proposed to be investigated in a range of Saskatchewan soils. Specifically, the proposed research examines the effect of soil and foliar applied Zn fertilizers on zinc concentration and phytate content of three different classes of lentil. A trivariate model of Zn absorption will be used to estimate Zn bioavailability in the lentil grain. Re-mobilization and distribution of Zn with the lentil plant as a function of lentil class type, and Zn fertilization practice will also be evaluated.