Impact of Tiller Inhibitor (tin) Gene and Nitrogen Application on Yield Components and Nitrogen Status (NNI) in Wheat.

The doctoral thesis begins with an introductory section highlighting the significance of cereals, particularly soft wheat and durum wheat, as key crops used for bakery products and pasta production, respectively. The research, motivated by the growing global demand for food, aims to enhance cereal varieties in terms of both productivity and quality. Tillering plays a crucial role in determining wheat yield and its competitiveness against weeds. Genetic and environmental factors significantly influence tillering, providing opportunities to select more efficient wheat varieties. Nitrogen is a vital macronutrient for crop production. Nitrogen use efficiency (NUE) is critical for sustainable crop management, involving the optimization of nitrogen uptake and utilization to maximize yield while minimizing environmental impact. The first chapter presents a field trial investigating the effects of the tin gene by comparing two pairs of near-isogenic lines (NILs) of bread wheat (Triticum aestivum L.), namely Janz±tin and Kite±tin. The experiment involved sowing 350 germinable seeds per square meter across six environmental conditions (two sites over three years) in Italy, specifically in Sardinia and Emilia-Romagna. The second chapter explores the impact of nitrogen (N) management on the yield and yield components of durum and bread wheat. This study was conducted over three growing seasons (2018/19, 2019/20, and 2020/21) at the University of Sassari's experimental station in Oristano, Italy. The research examined two durum wheat cultivars (Ramirez and Nazareno) and two bread wheat cultivars (Gioconda and Mona Lisa) under three nitrogen fertilization levels (N0, N80, and N160). Sustainability is a central objective in cereal production. Practices such as precision agriculture and crop rotation not only enhance productivity but also conserve resources. The challenges posed by climate change necessitate innovative solutions, including the development of drought- and heat-resistant varieties. The future of cereal production depends on integrating traditional knowledge with advanced technologies. Collaboration among researchers, policymakers, and farmers is crucial for translating scientific advancements into practical solutions. Continuous research and innovation will ensure cereals adapt to environmental challenges and meet the evolving demands for food.