Phenotyping the Effects of Simulated Spring Frost on the Yield of Barley (Hordeum vulgare L.) and Wheat (Triticum aestivum L.)

The climate change has led to an increase in the number of relatively warm days experienced in Central Europe during the late winter and early spring periods. These conditions have resulted in an early onset of vegetation, thereby elevating the risk of spring frost damage. The present study investigates spring frost tolerance in sets of bread wheat and barley accessions, with experiments conducted over a period of 2 years. In both species, the occurrence of spring frost during the flowering stage resulted in a reduction in grain yield, manifested as a decrease in the number of grains and a concomitant reduction in grain size. In barley, an additional association was observed between yield reduction and a decline in the number of tillers and heads following freezing. The detrimental effects of spring frost can be amplified when low temperatures are followed by drought. When water availability is not limited, plants begin to establish new heads, which in the case of wheat may partially compensate for decreasing yield. However, the practical impact of this effect may be limited by unequal maturity. There was a significant range in the extent of the reduction in yield following spring frosts between accessions, which offers a promising opportunity for breeding more resilient varieties.