Diurnal stomatal apertures and density ratios affect whole-canopy stomatal conductance, water-use efficiency and yield
| Date/Time: | Wednesday, 02 Feb 2022 from 2:00 pm to 3:00 pm |
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| Location: | Virtual via Zoom |
| URL: | https://iastate.zoom.us/j/98157476742?pw...E0NWNrZz09 |
| Phone: | 515-294-1360 |
| Channel: | Agronomy Department |
| Actions: | Download iCal/vCal | Email Reminder |
Key physiological traits of plants, such as transpiration and stomatal conductance, are usually studied under steady-state conditions or modeled using only a few measured data points. Those measurements do not reflect the dynamic behavior of the plant in response to field conditions. To overcome this bottleneck, we used a gravimetric functional-phenotyping platform and a reverse-phenotyping method to examine the dynamic whole-plant water-regulation responses of tomato introgression lines and compared those responses with several years of yield performance in commercial fields. Ideotype lines had highly plastic stomatal conductance and high abaxial-adaxial stomatal density ratios and the size of their stomatal apertures peaked early in the day under water-deficit conditions. These traits resulted in dynamic daily water-use efficiency, which allowed for the rapid recovery of transpiration when irrigation was resumed after a period of imposed drought. We found that stomatal density, the abaxial-adaxial stomatal density ratio and the time of maximum stomatal apertures are crucial for plant adaptation and productivity under drought-stress conditions. Abaxial stomatal density was also found to be strongly correlated with the expression of the stomatal-development genes SPCH and ZEP. This study demonstrates how a reverse functional phenotyping approach based on field yield data, continuous and simultaneous whole-plant water-balance measurements and anatomical examination of individual leaves can help us to understand and identify dynamic and complex yield-related physiological traits.