Executive Summary : | Plants face extreme temperature fluctuations due to their sessile nature, diurnal variation, seasonal variations, and the warming global climate. They grow in two non-overlapping material phases: the aerial phase of the shoot system and the soil phase of the root system. The difference in temperature distribution between these phases is often overlooked when studying the effect of temperature on plant growth. In a moderate climate, air temperature can vary from 20-35°C in summer to 10-25°C in winter, while under-soil temperature remains relatively invariant throughout the year. Soil surface temperature change is more extreme compared to air temperature, measuring from 5-40°C. Different tissues of growing plants experience different temperature dynamics over the day and seasons, with the optimal temperature of one tissue appearing as an extreme temperature of another. This is important for agriculture, as food products consist of diverse tissue types of aerial and under-soil origin. Most experiments on the effect of temperature on plant growth and performance have been carried out in the aerial phase, primarily due to the technical challenge in designing plant growth space that can simulate natural temperature variation and its extreme forms. The Department of Mechanical Engineering's Co-PIs have been working on designing new plant growth devices, such as aeroponics chambers and polyhouses, with control over various environmental parameters. This proposal proposes combining the technical expertise of the Co-PIs in engineering plant growth modules with differential temperature and the PI's study of environmental factors on plant growth and development. Growth modules will be designed and fabricated with two distinct temperature domains and tested under varying temperature regimes, as well as the effect of such changes on gene expression/function. |