The great Swedish botanist Carl Linnaeus established a plan for the classification of plants in his 1735 publication, Systema Naturae. Linnaeus divided the natural world into kingdom, phylum, class, order, family, genus, and species. He developed binomial nomenclature, which assigned a two-word unique name to each species: the first word described the genus, and the second, the species.
Linnaeus’s binomial nomenclature established a universal system of naming plant and animal species that provided order to a formerly chaotic, descriptive system that could have one species of flower described in multiple ways.
Linnaeus’s taxonomy system is still in use today, with subclasses and categories identified as scientists make new discoveries. DNA analysis has changed some of Linnaeus’s conclusions, but the overall structure of his classification system, especially his binomial nomenclature, is still standard in the natural sciences.
Linnaeus had a microscope, but oddly, he didn’t seem terribly interested in it. He wrote only one work about microscopic observation, Mundum Invisibiliem, when he was trying to figure out where to place fungi in his classification scheme.
However, history has recognized how important microscopes are to carrying on Linnaeus’s work of discovery and classification. Here we list 5 benefits of looking at plants under a microscope.
Placing a very thin sliver of plant material under a microscope offers the observer the opportunity to see cell structures within the plant. With increased magnification, curious explorers can see that cells are more than just blobs with a border and a center, but complex structures that carry out the following important functions necessary to a plant’s lifecycle.
Using high-powered microscopes, plant scientists have developed a new hypothesis about how plants grow. Previously, botanists thought that simple pressure against plant cell walls caused expansion. A newer idea put forth by researchers at the Université Paris-Saclay posits that the “rigid” walls of plant cells may have an intrinsic ability to grow.
In his Systema Naturae, Linnaeus outlines a description of plant reproduction, comparing it to human reproduction with analogies to a bride and groom. But until recently, it has been impossible to observe the processes of plant reproduction. Developments in microscopy now make it possible to observe the plant reproductive process as it happens. Understanding how plants reproduce may be central to saving endangered species and propagating beneficial plants.
Looking at plant cells under a microscope can reveal evidence of environmental stresses and damage. While a plant may look healthy at the macroscopic level, at the cellular level it may be suffering damage from environmental stresses such as climate change or toxic pollution. Microscopic observation can be an early warning system of crop stresses, alerting scientists to impending dangers to the food supply.
Like environmental impacts, botanists can observe and identify plant diseases using microscopes. Parasites, insects, bacteria, fungi, and viruses may cause disease and death in plants up to and including old-growth trees. Identifying the source of a plant’s distress could help with early intervention to treat the underlying cause, or to protect neighboring specimens from the spread of a plant pathogen.
During his lifetime, Linnaeus never traveled beyond northern Europe. But as European nations developed economic systems based on seafaring and global trade, students and admirers of Linnaeus went along for the ride and returned samples of previously unknown plant species to him for classification.
Linnaeus’s work of classifying and organizing the natural world didn’t stop with his death in 1778. Naturalists continued his work globally, while microscopes simultaneously developed more powerful lenses.
Today, DNA analysis can identify the genetic makeup of plant species and place them more accurately in the right classification or establish a new species altogether. One of the most important applications of genetic analysis of plants is to confirm compliance with international “genetically modified organism” standards. DNA testing can establish whether the “non-GMO” label is accurate. Fluorescence microscopes use fluorescence rather than, or in addition to, reflection, attenuation, or absorption of light to analyze a sample and can be used to identify genomic aberrations in plant cells.
Field Work and Education
Until recently, samples had to be delivered to labs that harbored the microscopes used to examine them. Now, however, portable microscopes make field study of plant specimens possible. Foldable microscopes can tuck into a backpack or pocket. Researchers can prepare slides at the site where a plant is growing and observe a specimen’s live attributes right at the time the scientist collects it.
Portable microscopes, inexpensively made of paper and a small lens, can work with cellphones to upload images for analysis at labs thousands of miles away from the exploration site. Researchers can work together much more quickly to identify species, diseases, or environmental damage to plant life.
Perhaps the most important benefit of looking at plants under a microscope is educational: when children who have never had the opportunity to use a microscope in scientific exploration first peer through a Foldscope lens, their reactions are of amazement, wonder, and best of all, curiosity.
Encouraging curiosity in young minds is the cornerstone of building a better future not just for those individual kids, but for the global community. Children in far-flung areas of the world have used these microscopes to help with crop management, identifying areas that should be isolated to prevent the spread of plant pests.
The abundance of plant life on this planet is astonishing: from the lush rain forests of Central and South American to hardy urban trees and even weeds that sprout from cracks in the sidewalk, plant life is everywhere. Using microscopes to gain a better understanding of the structure and lifecycles of these plants helps us understand the natural world and our responsibility as stewards of it.
When used to observe plant life, microscopes can be the canary in the coal mine of global environmental health. But they can also be the inspiration for kids who will grow up to be instrumental in finding solutions to medical, environmental, and ecological challenges of the future.