Breeding has selected for architectural and photosynthetic traits in lentils

Genetic progress in seed yield in lentils (Lens culinaris Medik) has increased by 1.1% per year in Australia over the past 27 years. Knowing which plant traits have changed through breeding during this time can give important insights as to how lentil yield has increased. This study aims to identify morphological and physiological traits that were directly or indirectly selected between 1993 and 2020 in the Australian lentil breeding program using 2 years of experimental data. Major changes occurred in plant architecture during this period. Divergent selection has seen the release of varieties that have sprawling to very upright types of canopies. Despite this genetic diversity in recently released varieties, there is an overall tendency of recently released varieties having increased plant height and leaf size with reduced number of branches. Increased light interception was positively correlated with year of release (YOR) and yield, and likely results from indirect selection of yield and taller plant types. There is an indication that recently released varieties have tower CO2 assimilation rate, stomatal conductance and canopy temperature depression (CTD) at high ambient temperatures (similar to 30 degrees C). Understanding lentil physiology will assist in identifying traits to increase yield in a changing climate with extreme weather events.

Automated summary

The seed yield in lentils has increased by 1.1% per year in Australia over the past 27 years. Changes in plant traits, such as increased height and leaf size with reduced number of branches, have occurred through breeding. Increased light interception and physiological changes, such as higher CO2 assimilation rate and lower canopy temperature at high temperature, are associated with improved yield in recently released varieties.