Project
Effect of rice growth dynamics and plant architecture on photosynthetic capacity
Sustaining rice production under water deficit is a key global goal. In this project the aim is to see how canopy morphology, whole plant water use, and biomass production are linked via photosynthesis to plant growth rate and investment under water stress.
Project description
The phenology of crops is a key crop trait that can influence the response of yield to environmental stress. Phenological development determines the rate of water use and the rate of carbon and nitrogen investment in different organs, especially leaves, impacting photosynthesis. These differences in growth rates can also affect photosynthesis by leading to different canopy structure and hence, different light and nitrogen profiles. This can also change the amount of pigments along canopy depth. These dynamics would ultimately impact the rate of plant water use and biomass production.
We want to test the interconnectedness between leaf-level to plant-level growth rates and their impact on plant morphology, water use and biomass under water stress. More specifically, we want to test these relationships at different canopy depths, and different watering regimes. We will do this in two contrasting rice varieties with different sensitivity to water stress.
Objectives and methods
Key questions:
- Is canopy architecture related to growth rate and biomass production of the plant?
- Does light penetration of open canopies mean a more evenly distributed nitrogen?
- Do those differences in nitrogen profile lead to different chlorophyll content (SPAD) down the canopy?
- Does change in SPAD down the canopy affect photosynthesis and stomatal conductance?
- How is this related to whole-plant water use and biomass production.
Key measurements:
- Rate of leaf appearance and expansion
- Daily whole plant transpiration
- Leaf morphology and stomatal anatomy along the canopy
- Leaf elemental composition along the canopy
- Aboveground and belowground biomass harvest
- Light canopy distribution
- Porometer/fluorometer using Li-600, with dark adaptation clips.
- SPAD, leaf thickness and other leaf level photosynthesis parameters.
- Absorptance and transmittance of leaves
Expectations
Student should be willing and capable, after appropriate training, to conduct sampling and data collection by themselves inside the climate room, and able to conduct the measurements using the techniques above.
Required skills
Understanding of general agronomic principles, alongside willingness to work in the lab and growth rooms collecting data. Some experience in data analysis will be desirable, but student will get more training throughout.
Types of research/work
Experimental sampling inside the climate room and then analysis of samples in the wetlab.
Period
June 2024 to November 2024
Location
Unifarm climate controlled chamber