Learn how do plants respond to heat and apply defense mechanism that helps them survive the hot season? How does it work in different species?
Sooner or later, summer will come. Many of us get used to the mild spring weather until the temperatures soar, and then, suddenly, we start to miss spring.
Heat affects not only us, it also affects plants.
During excessive heat, plants try to survive by trying to pull enough water out of the ground quickly enough to compensate for the moisture lost when it evaporates from the leaves.
Many biochemical reactions that are necessary for growth and reproduction are temperature sensitive.
Plants use physiological, biochemical, morphological, and molecular responses to heat stress.
How do plants respond to heat: how it works
When high temperatures are repeated year after year, plants can develop a memory of heat stress (thermopriming) that, when triggered, adapts them to minimize temperature damage (thermotolerance).
They can also adapt their leaves and other structures to better cope with heat.
Some of the mechanisms of thermal acclimation and adaptation of plants to high temperatures include changing leaf orientation, curled leaves, or fine hairs that shade the leaf surface; all of these reduce sun exposure and heat absorption.
Or the leaves may be covered with a thick waxy cuticle that retains water.
Reduced leaf size or changes in leaf shape or color are common types of adaptation.
Smaller leaves have less surface area exposed to the sun, lose less water, and stay cooler than larger leaves.
Gray leaves absorb less sun than dark green leaves.
Plants often lose leaves when they suffer from extreme heat stress.
Fewer leaves mean less water loss through pores called stomata, which are found in leaves, stems, and other plant organs.
Developing buds and fruits may drop.
In addition, plants can change their metabolism under heat stress. This may include changes in cell water content, cell salt content, proteins, and phytohormones.
How do plants respond to heat can also affect their growth. Some species simply avoid growth during the hottest time of the year by going into dormancy.
Reactions to heat stress and adaptation depend on the species and the stage of development.
Researchers are breeding plants for heat tolerance in order to support crop production worldwide in the face of longer hot seasons.
How to help plants survive the heat?
In order to help your plants survive the heat:
- Water them heavily in the early morning. Deeper roots tolerate heat better than surface roots.
- Mulch the soil to reduce evaporation of moisture in the soil and keep the soil cooler.
- Avoid fertilizing with anything other than slow release fertilizer or compost when it is hot.
- Rapid release fertilizer causes new growth that is tender and extremely vulnerable to heat damage.
The adaptation of plants to high temperatures is an extraordinary proof of the resilience and ingenuity of nature. Through a complex interplay of physiological, biochemical and molecular mechanisms, plants have evolved sophisticated strategies to overcome heat stress and ensure their own survival in the environment.
From morphological adaptations, such as leaf modifications and stomatal regulation, to biochemical tweaks, such as the synthesis of heat stress proteins and osmoprotectants, plants show remarkable plasticity in response to temperature fluctuations.
In addition, the role of genetic variation and epigenetic regulation in shaping plant thermal tolerance emphasizes the dynamic nature of adaptation processes.
As climate change continues to pose unforeseen challenges to the world, understanding the mechanisms of plant heat tolerance is becoming increasingly important for sustainable agriculture and environmental protection efforts.
By uncovering the complexities of plant adaptation to heat, researchers can develop innovative strategies to increase crop resilience, reduce environmental impact, and ensure biodiversity in a rapidly changing world.