How do plants respond to changes in temperature?
Climate change is influencing the temperature and weather patterns around the world.
Understanding the consequences for the world around us is complex but can help us reduce the impact of these changes on our everyday lives.
With that in mind, we sat down with Genes in the Environment Programme Manager Dr Teresa Penfield to discuss the work being done.
“In the UK the temperature is expected to rise by 2 – 4 °C by 2080; winters are predicted to get wetter by up to 30%, while our summers could get up to 40% drier.
Irreversible losses of some natural habitats are anticipated and impacts on crop productivity are already being seen at regional scales. Extreme weather events such as the heat wave in 2018 caused low yields of many UK crops from carrots through to cereals.
The global effects of climate change also influence the availability of our food through crop failures and impacts on our trade networks.
Adaptation strategies are necessary to secure food supplies for the future. These include breeding new crop varieties which are capable of withstanding and even excelling in the new and changing environmental conditions.
Plants adapt to the environment by using temperature signals to prepare themselves for the next stage of the growing season.
The different growth stages such as seed germination, flowering and seed set are fine-tuned to take place in narrow temperature ranges normally experienced at specific times of year. For this reason, climate change can have massive effects on ecosystem function and food crops.
In the Genes in the Environment (GEN) strategic programme we aim to understand how changes to the environment and particularly temperature influence plant development.
We use genetics to identify which genes are regulated for a plant to grow and develop in a way that is adapted to their environment.
To inform our crop breeding we first need to understand how plants perceive temperature, the genes which are regulated in response to temperature and the developmental processes which allow the plant to grow and develop in alignment with their environment.
By improving our understanding of how the environment influences the way plants grow and develop, we can inform strategies for developing more resilient crops and also improve the accuracy of modelling outputs of the anticipated outcomes of climate change on food security.
Since the beginning of the GEN programme in 2017, we have made significant advances in our understanding of how temperature influences plant development.
Our findings are helping us to identify both the genes and processes important for the timing of flowering, pollination and fruit and seed development which allow plants to fine-tune these processes to fit in with seasonal changes.
Increasing tolerance to a greater range of temperatures is important when breeding for yield resilience.
Flowering and vernalization
During flowering, pollen is produced in a structure called the anther where it is nursed by specialised tissue called the tapetum.
Our research has shown that tapetal cells are highly sensitive to temperature and that this is important for the range of temperatures in which pollen can be produced successfully. We have also identified a candidate gene in wheat which confers tolerance to both high and low temperatures during the production of sperm cells in plant reproduction.
After seed development many plants control the dispersal of their seeds by regulating when their seed pods break open, a process known as dehiscence.
We have shown that increased temperature is associated with faster and more frequent pod dehiscence, which can result in a major loss of yield before a crop is harvested. Understanding the genetics behind this process can allow us to breed for plants with stronger pods that are less likely to disperse their seed early.
A major focus of our research is understanding the changes which take place in plants in response to temperature as they begin to flower.
In places which experience a cold winter, this transition often occurs to enable the plant to flower in spring. The process in which flowering is accelerated by winter is known as vernalization.
The gene FLC plays a central role in this vernalisation process, and we have demonstrated by investigating FLC in the model plant Arabidopsis that variation in autumn levels of this gene enables plants to adapt to growing at latitudes with different climates.
In winter wheat we have shown that warmer temperatures during the early stages of plant development delay flowering and also result in an altered inflorescence structure which has implications on wheat yields.
To facilitate our research, we have developed new tools for manipulating vernalisation in a field environment at our Dorothea de Winter Field station, so that vernalisation can be interrupted or delayed and effects on yield components monitored.
We have also used specialised Controlled Environment Rooms which allow us to precisely mimic natural temperature, light and humidity variables so that we can verify and interpret our findings in the field using precisely controlled conditions.
It had been assumed that vernalization takes place over winter.
However, by moving our research into a field environment we have discovered that vernalization in oilseed rape usually takes place in October. We have found that if Octobers are warm vernalisation is delayed, which influences seed yield the following spring.
Future research plans
We are now working on identifying the genetic components that influence how much cold is required to enable a plant to flower. This is important for enabling us to select and breed crops in the future which are capable of producing high yields even if winters are warmer.
Our research is providing insights into how temperature influences the way plants survive and successfully reproduce.
We anticipate that our research will help us to understand the genetics underlying whether or not a plant can withstand the changes in temperature we are expecting through climate change. This will inform how we might introduce mechanisms of temperature tolerance into our crops to help secure global food supplies as the temperature rises.”