Epsilon Archive for Student Projects

Abstract

Spring wheat (Triticum aestivum L.) plays a crucial role in global agriculture, yet its productivity is severely impacted by drought and heat stress, particularly under
changing climate conditions. This study aims to evaluate the tolerance of ten Swedish spring wheat lines to drought, heat and combined drought and heat stress in controlled conditions. Selected lines, representing high and low yield stability under field trials, have been assessed for traits such as stay-green ability during senescence, chlorophyll content, chlorophyll fluorescence, leaf temperature, canopy temperature and yield. Using advanced measurements, including digital biomass, Soil Plant Analysis Development (SPAD) and fast chlorophyll a fluorescence induction (OJIP), the study identifies phenotypic markers linked to stress tolerance. Statistical analysis, including ANOVA, principal component analysis (PCA) and correlation studies, was performed to explore relations between traits and treatments of the different genotypes.

There were clear differences between the genotypes in multiple of the tested traits based on if the plants were grown in non-stressed or stressed conditions. There was a clear distinction between the treatments, with negative effects for the stressed plants in relation to both yield, growth, chlorophyll content and photosynthetic activity. Control treated plants had the highest yields, followed by drought, heat and combined stresses. PCA showed that difference between treatments were mostly due to difference in yield, leaf temperature and canopy temperature, while difference between genotypes largely depended on phenological traits such as days to heading and days to anthesis.

This research will contribute to the development of resilient wheat varieties and inform breeding strategies for climate adaptation, with implications for sustainable cereal production under environmental stressors.