Assessing the Impact of Grain-Filling Temperature on the Amylose Content, GBSSI Gene Expression, and Plant Growth in Tartary Buckwheat (Fagopyrum tataricum) for Climate Resilient Crop Production

Abstract

Crop production and food systems are increasingly affected by global warming and climate change, which pose challenges to the growing demand for food. This study focused on the impacts of high temperatures during the grain-filling stage on Tartary buckwheat (Fagopyrum tataricum), a nutritious and functional crop with unique ripening habits. The amylose content, relative expression of the granule-bound starch synthase I (GBSSI) gene, and various plant growth parameters were investigated under controlled growth chamber conditions. Three treatment groups with different air temperature regimes were established: low temperature (LT: 15/10 °C), moderate temperature (MT: 20/20 °C), and high temperature (HT: 30/25 °C). Results revealed that the HT treatment significantly decreased the amylose content of Tartary buckwheat seeds compared to the LT treatment. A qRT-PCR analysis indicated a decline in the relative expression level of the GBSSI gene in the HT treatment, particularly during the late filling stages. Pollen fertility also decreased with increasing temperatures, with the HT treatment exhibiting no fertile pollen at later stages. These findings highlight the negative impacts of high temperatures on Tartary buckwheat development, physiology, and reproduction. Understanding these effects is crucial for developing strategies to improve breeding programs and enhance food production in the face of climate change.