Researchers believe that breeding more drought-resistant crops may be possible with genetic discoveries made in recent years. As in plants, nutrient transportation takes place via the development of pipeline-like structures that carry nutrients to the leaves, and all of them are controlled by genes.
Plants can survive dry spells if they have specific genes found in their roots, say scientists at the University of California, Riverside.
- To do this, they instruct the plants to do the following:
- Providing water and nutrients with pipes-like vessels.
- Suberin supports liquid retention by acting as a barrier.
Root meristems determine the specific properties of the physical root, so they should be stimulated to grow.
The genes were discovered while scientists finished an atlas of crop roots, which are the first regions to detect drought in a seedling.
Professor of genetics and director of the Center for Plant Cell Biology Julia Bailey-Serres says that a molecular atlas offers a map of what is happening in cells. Furthermore, we find out which location they are in and find out what they are doing (such as transporting minerals, converting sugars, etc.).
Plants are dependent on their roots to endure, as they are the first to respond to threats that may arise from water availability and both good and bad microbes. The above-ground parts of the plants are connected to the underground parts of the plant by several types of cells.
Using rice as a model, her lab has studied flooding. She studied the role of distinct cells in the roots of wild tomato species under stressful conditions along with colleagues Siobhan Brady and Neelima Sinha. Sinha is an expert on plant growth and drought mechanisms, and Brady is a professor of plant biology at the University of California, Davis.
In this study, genetic information from indoor and outdoor tomato plants was combined to produce a better understanding of root functions.
Among the things the new gene code constructs for is the development of hollow, pipe-like vessels called xylem, which are responsible for transporting water and nutrients from roots to shoots. Besides protecting plants against drought and salt, these containers also protect against other environmental stresses. The process of photosynthesis cannot occur if xylem transport is not present.
“We found some xylem-specific genes that we expected (to find), but we have also found some that were unexpected,” Bailey-Serres said.
An outer root layer produced lignin and suberin in response to genes discovered in the second group of genes. Plant cells surround suberin, which is a layer of a biopolymer found on the outside of the cell wall that holds water in during a drought.
In a news release, suberin was stated to be present in the roots of tomatoes and rice. A layer of suberin surrounds the cells of an apple fruit as well. Whenever it is found, it can prevent plants from losing water. Moreover, cells are supported by lignin, which serves as a waterproofing agent and mechanical component.
“It was discovered that genes are encoding for both suberin and lignin in this very specific layer of cells, so it is possible to enhance their drought resistance”, said Bailey-Serres.
The genes responsible for this moisture barrier layer have been studied so in-depth that I am excited about what we have learned. Drought tolerance must be improved in crops to increase yields.”
Meristems are the growing tips of roots, where cells from which the root is made are housed. Studies have revealed that Arabidopsis, a plant commonly used for lab testing, and rice all appear to have the same genes that encode for the meristem.
“This is where the root grows and where stem cells develop,” she said. As a result, it determines the properties and the size of the roots. Three plant species that are evolutionarily distant from one another have very similar meristematic structures. This is unexpected in the plant kingdom.”
In response to stress, the researchers want plants to grow more, but grow “smarter.” Therefore, meristems may be used for this, or different meristems may be used for this purpose. A particular interest of scientists is how plants coordinate their activities above and below ground. Therefore, for breeders who wish to cultivate plants successfully, breeders must pay attention to the half of the plant buried below ground.
A root’s meristem can be modified to give plants more desirable properties. In addition to finding genes that make a crop more resistant to stress, crop modification involves searching for genes that do the same. If elsewhere is found, we can then begin breeding those varieties.
Later, genetic engineering can be applied. However, it is not considered genetic engineering in the United States when CRISPR-based gene editing is used.
Moreover, biotechnology companies are interested in investigating how roots deal with droughts and how they interact with good and bad microbes.
In addition to exploring how plants manage drought stress, the next step is to examine how they share data beneath the soil surface to modify growth above ground.
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