Efecto de los genes de vernalización VRN1 y fotoperíodo PPD1 sobre la fenología y los componentes de rendimiento en trigo

Wheat (Triticum aestivum L.) is an essential global crop due to its contribution to food security and its ability to adapt to diverse environmental conditions. In Uruguay, it is the main winter crop, with an average annual production of 1.13 million tons, highlighting its economic and productive significance. This study analyzes how the Vrn-11 and Ppd-1 genes, which regulate vernalization and photoperiod respectively, influence wheat phenology and yield components. Nineteen genetic materials, classified according to their allelic combinations for these genes, were evaluated across four sowing dates at INIA La Estanzuela, using a randomized incomplete block design with two replicates. Variables measured included growing degree days to first node, heading, and physiological maturity, as well as yield, number of spikes, grains per spike, and thousand-grain weight. Data were analyzed using mixed linear models to adjust means and determine significant differences among phenological groups.

The results showed that winter genotypes had slower development but achieved high yields in early sowings, making better use of initial climatic conditions. Spring genotypes insensitive to photoperiod stood out for their phenological stability and high yields across all sowing dates, demonstrating great adaptability. In contrast, spring genotypes sensitive to photoperiod exhibited longer cycles, better phenological adjustment, and greater stability in late sowings, reflecting robust adaptation to changing environmental conditions. Additionally, a positive impact of recent genetic improvement was observed, with materials showing higher productivity and better adaptability to variable conditions. Environmental factors such as radiation and temperature during critical crop stages also significantly influenced yield, underscoring their importance in crop performance.

This study emphasizes the interaction between vernalization and photoperiod genes and their importance in optimizing wheat productivity and stability in diverse environments. The selection of specific allelic combinations for these genes allows for the development of materials better suited to specific sowing dates and climatic conditions. The results provide valuable tools for breeding programs and agronomic management, essential for addressing the challenges of climate change and ensuring the sustainability of wheat production in Uruguay.