Ozone Tolerant Rice for Bangladesh: From Molecular Understanding of Tolerance Mechanisms to Field Application

孟加拉国的对流层臭氧浓度在过去二十年中急剧上升，并将继续上升，直到世纪中期。臭氧对稻米产量和质量产生负面影响，因此威胁到数百万稻米消费者的粮食安全。以前的工作已经揭示了水稻臭氧耐受性的遗传和生理方面，包括数量性状位点（QTL）的定位，以及潜在候选基因OsORAP1的分子特征。该项目扩大了这些发现，旨在开发适应孟加拉国不断变化的大气条件的水稻。该项目由两个工作包组成：（一）将在两个水稻季节使用化学臭氧保护剂乙撑二脲进行多地点实地试验。这将是孟加拉国有史以来第一次进行全面的臭氧影响评估和品种筛选。它将提供信息的时间和空间模式的臭氧损害和耐受性排名的20个广泛种植的水稻品种。(ii)将进行标记辅助育种方法，以将先前表征的耐受性QTL渗入臭氧敏感的本地精英背景中。将从臭氧生理反应和农艺性能两方面对选定的育种品系进行评估。该项目将增进我们对水稻对臭氧的反应和耐受性的了解，并有助于在世界上人口最多的发展中国家之一开发耐受种质。

Tropospheric ozone concentrations in Bangladesh have risen dramatically in the past twenty years and will continue to rise until the middle of the 21st century. Ozone thus threatens the food security of millions of rice consumers due to its negative impacts on rice yield and quality. Previous work has unraveled genetic and physiological aspects of ozone tolerance in rice, including the mapping of quantitative trait loci (QTL), and the molecular characterization of an underlying candidate gene OsORAP1. This project expands upon these findings, and aims to develop rice adapted to changing atmospheric conditions in Bangladesh. The project is composed of two work packages: (i) Multi-location field experiments will be conducted over two rice seasons using the chemical ozone protectant ethylenediurea (EDU). This will provide the first comprehensive ozone impact assessment and cultivar screening ever conducted in Bangladesh. It will provide information regarding temporal and spatial patters of ozone damage and tolerance ranking of twenty widely grown rice cultivars. (ii) A marker assisted breeding approach will be conducted to introgress previously characterized tolerance QTL into ozone sensitive local elite background. Selected breeding lines will be evaluated both in terms of physiological ozone response and agronomic performance. This project will advance our understanding of ozone response and tolerance in rice and contribute to the development of tolerant germplasm in one of the most populated developing countries in the world.