Gardening and botany are undergoing a true revolution thanks to the integration of genomic and molecular tools . These technologies, which until recently seemed reserved for cutting-edge research laboratories, are becoming key to understanding the diversity of our plants, improving them, and adapting them to the enormous environmental and production challenges we face.
Today, it is no longer enough to select plants based on their visible characteristics or to crossbreed them empirically. Advances in DNA sequencing, the development of new molecular markers, artificial intelligence, and gene-editing techniques such as CRISPR have opened up an immense range of possibilities, allowing us, in both agriculture and ornamental gardening, to design customized species and much better conserve plant biodiversity.
Genomic and molecular tools: concepts and applications
The incorporation of genomics and biotechnology represents a qualitative leap forward in the improvement and conservation of plant species. The techniques are highly varied, ranging from the most traditional, such as the use of morphological markers, to the latest developments in massive sequencing, artificial intelligence, and gene editing.
Molecular markers and genetic diversity analysis
Assessing genetic diversity is fundamental for both breeding programs and biodiversity conservation. Molecular markers, which are small fragments of DNA linked to specific regions of the genome, allow for the precise distinction of species, varieties, and even individuals, regardless of environmental factors. Among the most commonly used are:
- AFLP (Amplified Fragment Length Polymorphism)
- RAPD (Randomly Amplified Polymorphic DNA)
- SRAP (Amplified Sequence-Related Polymorphisms)
- ISSR (Inter-simple Sequence Repetitions)
- RFP (Restriction Fragment Length Polymorphism)
- SSR or microsatellites (Simple Sequence Repetitions)
- SNPs (Single Nucleotide Polymorphisms)
Dominant markers, such as RAPD or AFLP, allow for low-cost studies in less studied species, while codominant markers, such as SSRs or SNPs, offer much higher resolution and are ideal for advanced breeding and selection programs. Furthermore, the current trend is clearly toward using SNPs due to their abundance and precision, especially with the reduced cost of next-generation sequencing (NGS).
Hybridization matrices and high-throughput technologies
Hybridization arrays, especially those based on SNPs and platforms like DArT, have significantly increased the capacity to analyze many individuals and loci simultaneously. These arrays allow for the characterization of genetic variation in large germplasm collections, identifying genes of interest for disease resistance, yield, or quality, all without the need to cultivate or cross the plants first. Furthermore, DArT arrays do not require prior sequence information, which reduces development costs and makes them ideal for understudied species.
Massive sequencing: the NGS revolution
Next-generation sequencing (NGS) has democratized access to the complete genomic information of any plant. With these technologies, thousands of genes or entire regions of the genome can be analyzed simultaneously and rapidly. This not only helps identify important genetic variations but also makes it possible to map genes associated with key traits (QTLs), study population structure, and design much more efficient breeding programs.
Assisted selection and genetic improvement: markers, maps and strategies
Current plant breeding programs combine targeted crosses with marker-assisted selection. This strategy accelerates breeding cycles, as it allows for the identification, from seed, of whether an individual possesses the desired genes or variants, without waiting for it to grow or bear fruit.
Genetic maps are used to locate the QTLs responsible for traits of interest, such as disease resistance, drought tolerance, fruit or flower quality, and many other characteristics. This allows for much more precise and rapid selection. This methodology is already successfully applied in crops such as grapes, fruit trees, and vegetables, and increasingly in ornamental and forage species.
To learn more about how these genomic tools can be applied to the improvement of ornamental species, see the article on primitive plants and their applications in gardening.
Apomixis: natural cloning and its advantages for improvement
A key phenomenon in many species of agricultural and ornamental interest is apomixis, the ability to produce viable seeds without sexual fertilization. In this process, plants generate genetic clones of the parent plant, allowing for the maintenance of hybrids with superior characteristics or the fixation of desired traits without the problem of genetic segregation.
Apomixis can be gametophytic or sporophytic and is widespread in families such as the Poaceae. For breeders, the rapid identification of apomictic plants is extremely useful, and molecular markers are used to distinguish them even at early stages, greatly streamlining the selection of potentially commercial lines.
Furthermore, understanding the genetic regulation of apomixis through linkage mapping and QTL analysis opens the door to attempting to transfer this mechanism to other crops using classical methods or genetic engineering, although significant challenges remain in this area.
Genome editing: The role of CRISPR in gardening and botany
Perhaps the most disruptive tool of recent years is genome editing with CRISPR/Cas9. This technique, derived from the bacterial adaptive immune system, allows for the precise cutting and modification of any region of the plant genome. The best part is that it can be done without introducing foreign DNA, which facilitates the social and regulatory acceptance of many of these new plants.
The practical applications of CRISPR in horticulture, fruit growing, and ornamental gardening are immense: eliminating genes that generate allergens, creating seedless (parthenocarpic) fruits, obtaining varieties that are more resistant to disease or environmental stress, modifying the color or shape of flowers and fruits... All of this is no longer science fiction, but an experimental and, in some cases, commercial reality.
In complex species such as forages or high-value ornamental plants, where self-incompatibility and polyploidy make conventional breeding difficult, CRISPR offers a way to introduce rapid and controlled changes. Furthermore, increasingly faster methods are being developed that do not require stable genetic transformation, such as the use of protoplasts, making editing possible even in species that are difficult to manipulate.
Artificial intelligence and high-throughput phenotyping
Artificial intelligence (AI) and deep learning have begun to revolutionize plant phenotyping. Models like GenoDrawing allow for the prediction, based on genetic information (for example, SNP profiles), of complex traits such as fruit shape, color, or even plant size, generating realistic images before the plant has grown or fruited. This greatly speeds up breeding programs and takes assisted selection to a new level of precision and speed.
These methodologies also help reduce costs and avoid errors inherent in traditional evaluation, which often depends on manual observation and is limited by plant development times.
Innovation and challenges in modern plant breeding
The introduction of genomic techniques not only accelerates the development of new varieties but also allows us to face challenges that until recently were insurmountable. For example:
- Obtain plants free of allergenic compounds, such as low-gluten wheat lines, specifically designed for people with celiac disease.
- Introduce simultaneous resistance to multiple abiotic and biotic stresses in key species for global food and gardening, such as corn, rice, tomato, grapevine, and roses.
- Develop ornamental and gardening materials with new visual or physiological characteristics: pollen-free plants, flowers with unique colors, or controlled growth to facilitate their use in parks and urban spaces.
