Whispers of the Green

Introduction

In the realm of nature, a symphony unfolds between plants which eludes the human ear, one which allows plants to communicate over unimaginable distances; from underground root networks to airborne chemical signals, this article will explore the secretive world where flora displays its communicative capabilities to one another. The hidden language of plants which shapes our ecosystems, influences growth patterns, and hints at a collective intelligence prospering beneath our botanical companions will be talked about here and, to finalise this article, human applications regarding this knowledge will also be discussed.

Ways in which Foliage Interact:

Root Networks

The most obvious form of possible communication between plants occurs between their roots. Plants talk to each other through their roots by releasing chemicals into the soil. This communication, called allelopathy, involves sending substances that affect how neighbouring plants grow and behave. A study by Callaway and others in 2005 showed that these chemical exchanges influence the competition and distribution of plant species. The research found that some plants release substances that hinder the growth of nearby competitors, giving them an edge in getting water and nutrients. This chemical communication not only affects individual plant growth but also influences where different plants thrive in an ecosystem. Essentially, plants use these chemicals to shape their environment and gain a competitive advantage.

Symbiotic Relationships

Unlike previously, where plants use the communicative abilities to enhance their competitive attributes, they can also use it to create positive relationships with other species. For example, the mycorrhizal association (top left), is a type of relationship which occurs between a plant and fungi is a cooperative relationship which enhances nutrient acquisition for plants. The fungi extend the plant's root system, and in return, the plant provides the fungi with carbohydrates produced through photosynthesis. Another notable symbiosis involves certain plants and nitrogenfixing bacteria. Within this association, plants convert atmospheric nitrogen into a usable form, and in return, bacteria receive sugars from the plants. All in all, plant’s ability to communicate with other flora enables them to survive in environments where they wouldn’t be able to do so alone.

Chemical Signalling

The Venus flytrap (top right) presents a unique chemical characteristic involving the secretion of jasmonic acid to enable the closure of its trapping structure. This intricate response is not only purposed for prey capture but serves a dual purpose as a deterrent to herbivores as-well, signalling potential danger and preventing them from consuming the plant's foliage. Furthermore, the Venus flytrap engages in a form of chemical communication through the release of jasmonic acid into the environment. This serves as a means of signalling to neighbouring Venus flytraps, prompting them to be wary and possibly secreting their own jasmonic acid to deter potential threats. In essence, the Venus flytrap presents the cooperative nature of plants with one another.

Electrical Signalling

A study conducted discovered a mechanism of communication among plants, focusing particularly on electrical signalling. It unveiled that when one plant undergoes stress, such as from injury or excessive sunlight, it emits an electrical signal. Surprisingly, this electrical message has the ability to be transmitted to a neighbouring plant, even if it belongs to a different species. This communication creates changes in the plant's physiology, including photosynthetic processes. The findings highlight the extent to which collaboration among plants occurs and introduces the concept of “network acquired acclimation,” contributing significantly to our understanding of plant interactions.

Eavesdropping phenomena

Aside from possessing the ability to communicate with each other, plants can also act as a third-party, tapping into communications between other plants. In the eavesdropping process of plants, volatile organic compounds (VOCs) are released by a stressed plant into the air. Nearby plants detect these chemical signals and adjust their responses, activating chemical and physical changes. This adaptive mechanism enables plants to prepare for environmental challenges, providing advantages in terms of growth and survival.

Human applications and Hypothesises for the future:

Understanding how plants communicate could completely change how we view pest control (bottom right) in agriculture. Farmers, by identifying specific plant signals, can implement more precise and sustainable pest management strategies. Early detection through plant communication minimises the need for the broad use of pesticides, promoting environmentally friendly practices. This knowledge also opens options for developing pest-resistant crops through.

Knowing how plants talk to each other can also help create crops that handle climate change better. By understanding the signals plants send when stressed, scientists can develop crops that are more resilient. Breeding programs and genetic changes using this knowledge can produce crops that can better cope with temperature changes, lack of water, and other challenges linked to climate change. This means we could potentially grow crops that ensure food security in changing environments. Finally, hypothetically, knowledge surrounding how plants talk to each other can help create new medicines. By understanding the chemicals, they use to communicate, scientists might find compounds with medical benefits. Plants produce various bioactive compounds, and studying their roles could lead to the discovery of new medicines. This knowledge might also start the development of drugs that help boost our body’s immune system. Exploring plant communication is a promising way to find new compounds for healthcare. In conclusion, this article explained how plants communicate and describes how the understanding of plant communication is highly valuable in our live, such as through agriculture, pest management, climate resilience, and pharmaceutical discovery. Thus, the investigation of how plants communicate not only contributes to scientific knowledge but also creates solutions for advancing sustainable agriculture practices and healthcare solutions. (Take care in looking at the picture on the next page which summarises plants’ communicative pathways)

Key-words:

Symbiosis – a close association between two or more different biological species.

Mycorrhiza – A symbiotic relationship between a green plant and fungus.

Allelopathy -the chemical inhibition of one plant by another, due to the release into the environment of substances acting as germination or growth inhibitors.

Pesticides - Chemicals which destroy insects or other organisms harmful to cultivated plants or animals

Synoptic links :

GCSE: 11.9 - Plant Hormones and Responses (looking at how basic hormone can initiate processes of chemical signalling between plants)

11.10 – Using Plant Hormones (looking at the applications of Plant hormones in agriculture)

A-Level 19.2 –Variation in population size (Looking at how plant interactions can influence their likelihood of survival )

19.3 –Competition (Looking at how plants can use communication to gain a competitive advantage against neighbouring foliage)

10.1 – Species and taxonomy (Looking at how artifical selection could potentially be used in plants to create more pesticide-resistant strains )

References [cited 2024 Jan 18]

1. Callaway, R. M., Thelen, G. C., Rodriguez, A., & Holben, W. E. (2005). Soil biota and exotic plant invasion. Nature, 435(7044), 1098-1100.

1. Smith, S. E., & Read, D. (2008). Mycorrhizal Symbiosis. Academic Press. - Bonfante, P., & Genre, A. (2010). Mechanisms underlying beneficial plant–fungus interactions in mycorrhizal symbiosis. Nature Communications, 1, 48.
2. Frazer, J. (n.d.). The Venus Flytrap Can Count Past 2. [online] Scientific American Blog Network. Available at: https://blogs.scientificamerican.com/artful-amoeba/thevenus-flytrap-can-count-past2/#:~:text=The%20plant%20appears%20to%20use [Accessed 27 Jan. 2024].
3. Szechyńska-Hebda, M., Lewandowska, M., Witoń, D., Fichman, Y., Mittler, R. and Karpiński, S.M. (2022). Aboveground plant-to-plant electrical signaling mediates network acquired acclimation. The Plant Cell. [online] doi: https://doi.org/10.1093/plcell/koac150.
4. Karban, R., Maron, J., Felton, G. W., Ervin, G., & Eichenseer, H. (2003). Herbivore damage to sagebrush induces resistance in wild tobacco: evidence for eavesdropping between plants. Oikos, 100(2), 325-332