High-Throughput Phenotyping of Brachypodium distachyon under Progressive Drought and Heat Stress

Grasses, such as rice, wheat, maize and sorghum, are the primary caloric intake for humans and productivity is not projected to meet global demand by 2050. The geographical distribution of food and bioenergy crops is limited by several factors including temperature, soil salinity, and water availability. Although abiotic stress research in the dicot plant model, Arabidopsis, has been successful in elucidating pathways for cold, heat, drought and salt stresses, key questions still remain. There are also fundamental differences between monocots and dicots, which diverged 127-175 million years ago, such as grain development, plant architecture and cell wall composition. B. distachyon, is a C3 model grass closely related to wheat, barley, rye and rice. This study focuses on quantifying the phenotypic variation of model monocot B. distachyon under temperature and drought stress in order to identify genes important for increasing plant productivity under abiotic stress tolerance in grasses. An accession population of B. distachyon was analyzed under drought and temperature stress using a number of phenomics tools, including a high-throughput LemnaTec Scanalyzer 3D platform at the Donald Danforth Plant Science Center. Phenomics data was examined for traits such as growth-rate, biomass accumulation, integrated WUE, efficiency of photosystem II (Fv/Fm), and plant water content (near-infrared imaging) using open-source custom analysis software.