Regulação da resposta à deficiência de Zinco em Arroz e Sorgo

The risk of Zn malnutrition affects one third humans worldwide, especially in poorer countries (Wessells and Brown 2012), and Zn deficient-soils cause substantial losses in crop productivity (Alloway, 2008). Research on the physiology and genetics of plant micronutrient homeostasis is therefore needed to develop biofortification tools that can these and other problems (Assunção et al. 2022). The main objective of this project is to advance knowledge of plant Zn regulation, including translational research to crops, with the ultimate goal of producing proof-of-concept crop lines with enhanced Zn content and Zn-use-efficiency. The specific objectives are two-fold: - First, Tasks #1 to #3 clarify the mode of action of F-bZIP ZSM variants, which, as explained in the previous section, is necessary to support translational work to crops. - Second, Tasks #4 to #6 will provide evidence for the function of F-bZIPs in natural crops (rice and sorghum), and proof-of-concept lines for the effect of modulating F-bZIP activity on crop performance and seed Zn content. We chose to work with rice and sorghum crops for the following reasons: - Rice: Rice (Oryza sativa) feeds more than half the world population and is often used as a staple food. Rice is the predominant source of energy, protein and micronutrients for more than 50% of the world population, but it does not provide enough essential mineral nutrients to match human requirements; a typical rice-based vegetarian diet cannot fulfil the ca. 8-15 mg daily Zn requirement (Nakandalage et al., 2016). Portugal is the fourth largest European producer (ec.europa.eu), and rice has an important economic and cultural value in the country. Therefore, developing biofortification technologies for rice should be one of the most effective ways of fighting Zn malnutrition worldwide, and is also of economic interest for fighting poor crop performance in Zn-poor soils, including in Portugal. - Sorghum: Sorghum (Sorghum bicolor) is traditionally used as staple food in regions of Africa, middle-East and Asia, and in the West it has so far been used mostly as fodder for animal production. However, sorghum is now considered an emerging crop for ecologically-conscious agriculture, because of its water-use efficiency, tolerance to warming and nutrition value. Therefore, including sorghum in this research supports diversification in agricultural practices needed to respond to climate change.