硫代葡萄糖苷调控小白菜农药代谢降解机制研究

The high pesticide residue in vegetable is becoming a big problem of food safety and affected the sustainable development of vegetable industry. It is of great importance to study the mechanisms of pesticide degradation in vegetable for reducing the vegetable pesticide residues and assuring the food safety.Glucosinolates are the main secondary metabolism products of the Brassicaceae family including Brassica vegetables, which is of value to the flavor and nutritional qualities of this category food crops.The glucosinolate system is considered to be an efficient defense system for plant to be against many environment stresses including herbivore, microorganisms, fungus, wounding and chemical poisoning.It has also been proved that the degradation products of glucosinolates have strong anticarcinogenic properties.Hence,it is an effective strategy of modulating glucosinolates profile and content to enhance the tolerance of vegetable crops and improve the quality and safety of agricultural produces. .In this program,we will study the relationship between glucosinolates metabolism, plant growth and pesticide degradation metabolism in pakchoi with different glucosinolate profile and content by using molecular methods. Aiming to investigate the role of glucosinolates on plant pesticide degradation and illustrate the mechanism of pesticide degradation in pakchoi modulated by glucosinolates. We hope this study can provide foundation to guide agriculture practice of reducing vegetable pesticide residue and assuring food safety.

蔬菜农药残留已经成为影响我国食品安全和设施蔬菜可持续发展中亟待解决的重要问题之一。研究蔬菜作物农药代谢解毒机制对减少农药残留、保障食品安全具有重要科学和实践意义。硫代葡萄糖苷等植物次生代谢物质是植物防御体系的重要组成部分，在植物防御昆虫取食、病菌侵害、逆境胁迫、化学物质毒害等方面发挥重要作用。硫代葡萄糖苷是小白菜等十字花科蔬菜的主要次生代谢产物，与此类蔬菜的风味和品质有关，其水解产物还被证实对人体有抗癌作用。因此，调控硫代葡萄糖苷组分和含量，既可提高农产品品质，又能增强植物防御性。.本项目通过研究不同硫代葡萄糖苷组分及含量的小白菜在农药处理后硫代葡萄糖苷代谢-植株生长-农药代谢之间的相互关系，分析硫代葡萄糖苷组分及含量变化与小白菜农药代谢的关系，探明硫代葡萄糖苷在小白菜农药代谢中的作用机制，为了解十字花科作物农药代谢解毒机制、用生物技术手段减少农药残留、保障食品安全提供理论依据。

硫代葡萄糖苷是小白菜等十字花科蔬菜重要的次生代谢物质，是植物抵御包括化学毒害物质等逆境胁迫的防御体系的重要组成部分，也与此类蔬菜的风味和品质有关。而农药作为现代农业中非常重要的部分，对作物本身和环境都有不可忽略的影响。本项目主要着眼于农药与小白菜硫苷代谢之间的关联及其作用机制，研究不同硫苷组分及含量的小白菜在农药处理后植株生长、硫苷及农药代谢情况。结果显示，不同基因型小白菜在经过不同农药处理后，植株生长和硫苷代谢均受到了不同程度的影响。而随着农药自身的降解和植株对其适应性的增强，农药的作用慢慢减弱。同时，在一定浓度范围内，不同农药对硫苷合成基因表达的诱导和含量积累具有一定程度的促进作用，但作用模式可能因其本身代谢模式不同而有所区别。在农药处理后，植株硫苷合成基因的表达和硫苷含量积累间存在一定的关联。我们将在后期继续进行相关机制的研究。