Grain setting variations in wheat and barley exposed to pre-flowering heat waves.

CARRERA, CONSTANZA S; SLAFER, GUSTAVO A.; SAVIN, ROXANA

Lleida

Simposio; Fifth Symposium on Physiology and Cereal Breeding 2023; 2023

Universidad de Lleida

The probability of heat stress occurrence has been increasing steadily, compromising food security due to the negative effects on most crops’ performance. In fact, transient heat waves on crops will also be more frequent, negatively impacting yield. Thus, recognizing differences in sensitivity between crops that are grown alternatively on the same fields, like wheat and barley, is relevant. Grain number per unit area (GN/m2) is the main yield determinant and depends on the production and survival of floret primordia determining the number of fertile flowers (FF). We compared the sensitivity of wheat and barley to pre-flowering heat waves, analysing the responses on GN/m2 and its components. Treatments consisted of three well-adapted and high-yielding cultivars of each species exposed to two temperature levels: unheated (control) and heated plots using portable chambers with transparent polyethylene films for a brief period, during pre-flowering. Heating reduced yield in both crops, being mainly associated with GN/m2 reductions (P-value