Polyploid plants, which have multiple sets of chromosomes, have been found to be salt-tolerant, drought-resistant, and capable of producing higher yields. However, these plants are often sterile or have reduced fertility, making them unsuitable for breeding resistant lines due to incorrect pollen tube growth. The control of pollen tube growth is crucial in determining fertility, and researchers have identified two genes associated with this process that could be useful in crop breeding efforts.
In contrast to mammals and humans, where having multiple genomes is usually fatal, plants can benefit from polyploidy. They are better adapted to the environment, salt-tolerant, drought-resistant, and often produce larger seeds or fruits, resulting in increased yields. Despite these advantages, newly formed polyploid plants are typically infertile, making it difficult to propagate them. The exact reasons behind the reduced fertility in polyploids are still not fully understood, but recent research has shed light on a new mechanism for this phenomenon.
A study conducted by ETH researchers revealed that the pollen tube in newly formed polyploid plants does not grow properly, preventing fertilization from taking place. The discovery was made in sand rock-cress, where tetraploid plants have evolved to overcome the challenges of genome duplication and establish themselves in independent populations. By investigating genes associated with fertility in tetraploid populations, the researchers identified two genes that control pollen tube growth and influence the plant’s ability to reproduce successfully.
The ETH researchers found that the two genes responsible for pollen tube growth have evolved slightly in tetraploid individuals compared to diploid plants. Evolution has enabled tetraploid plants to vary these genes in a way that maintains fertility, providing insights into the mechanisms behind their adaptation to polyploidy. The discovery of these genes opens up new possibilities for plant breeding, as they are highly conserved and can potentially be transferred to other species.
Further research is needed to fully understand the infertility of newly formed polyploid plants and identify other gene candidates involved in pollen tube growth. The potential application of the newly discovered genes in plant breeding remains to be investigated, but the researchers are hopeful that transferring them to other species could lead to the development of new crops with desirable traits. By unlocking the secrets behind polyploidy and fertility in plants, scientists aim to leverage this knowledge to improve agricultural practices and crop yields in the future.
