Shh...listen to what little secrets the plants are whispering?

Figure 1 shows the tree-like Calligonum mongolicum. In order to resist heat and drought, the leaves of the tree-like Calligonum mongolicum are deformed, and the photosynthesis function is transferred to the new branches of the year, which are also called "nutrient branches" or "assimilation branches."

Figure 2 shows the light-branched Calligonum. The light-branched Calligonum is relatively cold-resistant and can safely survive the winter at extreme temperatures below -40°C without any frozen tips. It is very smart in that it can tolerate sand burials. When the lower part of its branches is buried in the sand, it grows faster and can quickly form new branches there. Photo by Duan Shimin

As the saying goes: There is nothing strange in the world. If scientists use some scientific means, there will be more incredible things that are beyond our imagination. In the middle of this month, two very "science fiction" news emerged: scientists "talked" with humpback whales for the first time; plants can make "sounds" to communicate.

The former reported that a US research team recently used an underwater speaker to successfully "talk" with a humpback whale and recorded the call of the humpback whale when it "contacted" the speaker. It is said that this "communication" shows a complex level of understanding and interaction, which is of great significance to the future search for extraterrestrial life.

The latter cited a paper published in the journal Cell by an Israeli research team, revealing the surprising side of seemingly quiet plants: tomatoes and tobacco emit ultrasonic "screams" when dried or their stems are cut; and earlier studies have reported that fungi change the pattern of electrical signals they emit when exposed to light or chemicals, and that plant roots emit signals when they are symbiotic. Do these phenomena mean that plants have "dialogue-like" interactions? If we "understand" the "sounds" emitted by plants, such as water shortages, wouldn't it be possible to achieve precision irrigation in agriculture?

The topic was extended and it was very interesting.

Darwin, a British biologist and founder of the theory of evolution, once wrote: "In the map of organisms, I am always happy to praise plants." Looking back at the evolution of plants, in terms of the "art of reproduction", from "asexual" to "sexual", from "bisexual" cross-pollination to "self-sufficient" self-pollination, the survival wisdom of plants has exceeded our imagination. Let's look at it again: the emergence of roots solved the problem of getting water, allowing plants to leave the water; the vascular bundles are intertwined and connected, making it possible for plants to transport water, inorganic salts and organic substances, thereby allowing plants to move from "primary" to "advanced".

Perhaps it can be said that plants are better evolved, more adaptable, and more "intelligent" species than we have always thought, although the term "plant intelligence" is quite controversial. In fact, as early as the beginning of the 20th century, scientists studied the responses of plants to various stimuli and pointed out that plants actively explore their environment, learn, and adjust their behavior according to their goals. The development of plant physiology in recent years has also prompted us to study plants as organisms that have the ability to obtain, store, share, process, and use surrounding information. One scholar even proposed that if "intelligence" is defined as the ability to solve problems faced in survival, then we really cannot deny that plants do have these abilities.

Studies have shown that even without neurons, plants can still process and integrate information with their own perception and response systems, thereby regulating their own physiology, growth and development, and morphology. Although plants cannot escape adversity through movement like humans and animals, they can actively adapt to environmental changes by integrating environmental information and their own physiological activities.

In the desert, water is a scarce resource. Desert plants have generally evolved various strategies to cope with water shortages. When water is extremely scarce, many plants will enter a dormant state. Once they are moistened by rain and dew, they can often quickly complete the entire process of germination, growth, flowering, and fruiting. In terms of morphology, the leaf surface area of ​​desert plants is generally reduced or degraded, or has undergone "metamorphosis" in evolution, becoming scaly, thorny, or leafless, which is very helpful in reducing the transpiration rate of plants.

I have seen an important desert vegetation community plant in Xinjiang, a "guardian" of windbreak and sand fixation - Calligonum mongolicum. Its leaves have shrunk into stipules and wrapped around the internodes of the branches, resulting in very short internodes of the branches. When growing, they twist and turn, which also makes this "pioneer in sand control" named "Calligonum mongolicum". What is particularly amazing is that Calligonum mongolicum can not only use assimilated green shoots to replace the function of leaves for photosynthesis, but also grow a layer of wax on its branches to avoid high temperature burns and water loss.

In fact, the rich polymorphism and plasticity of Calligonum plants are a manifestation of microevolution and evolution with the environment. This also makes it a "good material" for basic scientific research on classification and evolution in the eyes of biologists. It can involve multiple disciplines such as classical taxonomy, phenology, reproductive biology, cytology, anatomy and molecular biology. It is really amazing! What kind of ability is it?

Author: Yin Chuanhong