Waterlogging of Winter Crops at Early and Late Stages: Impacts on Leaf Physiology, Growth and Yield

What is the problem?

Crop production in various parts of the world is expected to become more vulnerable to prolonged waterlogging as a result of global climate change.

This study conducted at the University of Buenos Aires in Argentina investigated the tolerance of wheat, barley, field pea and rapeseed to 14-days of early or late waterlogging.

What did the research involve?

Wheat, barley, rapeseed and field pea were grown from seed and then subjected to three different treatments to determine their potential vulnerability to waterlogging stress.

Treatments that were compared included:

• plants used as a control were grown in well-drained media and watered daily,
• plants were grown in waterlogged conditions during early stages of development, (3) plants were grown in water logged conditions during the later stages of development.

Photosynthesis and internal CO2 were measured on fully expanded leaves of control and waterlogged plants. The formation or air channels was assessed in roots of control and waterlogged plants. Dry mass and seed production responses were also measured from all plants.

What were the key findings?

• There were substantial differences among the four winter crop species in tolerance to waterlogging.
• Wheat shows resilience to 14 days of waterlogging and while wheat leaf and shoot growth was not significantly affected by waterlogging in early- or late-stages of growth, seed production was reduced by up to 86% compared to controls.
• All leaf physiological parameters measured was affected by waterlogging which showed inhibited shoot and root growth due to early leaf senescence depending on the species and the timing of the waterlogging stress.
• Relative growth rate of shoots and roots were negatively affected by waterlogging stress by up to 78% of controls.

Final comment

• Some resilience towards waterlogging stress is seen to develop in its leaf and shoot growth. However seed production decreases substantially.
• Transient waterlogging during early plant stages of barley and rapeseed can still result in significant yield, but more adverse impacts were observed when waterlogged at the late stage.
• Field pea was not suitable for areas prone to waterlogging of 14 days at either growth stage.

This paper was summarised by Luke Stafford (Bachelor of Biological Sciences with Honours – Botany and Genetics Majors (La Trobe University)  and reviewed by Nickala Best  (PhD Student (La Trobe University).  Learn more about Luke and Nickala  here.