Dr Lia B. Olmedo Pico1, Dr Jeremy Whish1, Dr. Fernanda Dreccer1
1CSIRO Agriculture and Food
Biography:
Lia B. Olmedo Pico is a crop physiologist specialised in cropping systems and abiotic stresses. Lia has lead projects of field-based, data-driven agricultural research in the U.S. and Argentina, and she is now a CSIRO CERC Fellow focused on quantifying the yield response of lentil and chickpea to frost and heat events. Lia holds a B.Sc. in agricultural engineering from the University of Catamarca, a M.Sc. in crop physiology from the University of Mar del Plata, and a Ph.D. in cropping systems & crop physiology from Purdue University.
Abstract:
Lentil yield is sensitive to heat stress during key reproductive stages. To determine the quantitative response of lentil yield to high temperatures and its underpinning physiological mechanisms, we applied a two-fold approach. First, we studied the response of lentil variety PBA Jumbo 2 in terms of phenology, biomass accumulation and yield formation under contrasting water availability levels and sowing dates in a summer rainfall growing area (Gatton, QLD). Thermal time to budding -and flowering- was shortened with increasing water stress under both sowing dates. This response was partially explained by rainfed plants having higher canopy temperature, especially in the later sowing date. Increases in biomass accumulation due to higher water availability were mainly driven by differences in intercepted radiation with no changes in radiation use efficiency. Despite responses in phenology and biomass accumulation, yield did not change across treatments as increases in seed number were compensated by decreases in seed weight. In order to put these results in a broader context of genotypes and environments, we also investigated the main climatic drivers of lentil grain yield using data from the National Variety Trials (2005-2023). In this presentation, we discuss the effects of temperature on lentil yields using both sources of information.