A scientific team from the Faculty of Horticulture is analyzing seeds from various crops. Using laboratory methods, they are able to determine not only whether bacteria are present in the seeds, but also in what quantities. The research also includes the development of plant protection products, mostly based on nanomaterials or phenolic substances, which, thanks to their specific properties, are effective and have a lower environmental impact compared to conventional products. The research team is collaborating with MoravoSeed and the Institute of Chemistry and Biochemistry of the Faculty of Agronomy.
Most often, scientists test seeds for the presence of the bacterium Xantomonas campestris pv. campestris (Xcc), which causes bacterial black streak disease in cruciferous plants. Typical symptoms of this disease include V-shaped necrosis on the leaves and blackening of the vascular bundles. The seeds are immersed in a buffered solution for several hours, where they swell, then crushed, and the resulting homogenate is tested using both cultivation techniques and PCR-based methods. “The advantage of PCR is that only a very small amount of seed is needed to detect the presence of the bacterium – in practice, just a few seeds. In addition, it is possible to determine how many bacteria are present in the sample and thus determine the degree of infestation of the tested batch,” explained Jakub Pečenka from Mendelea – the Institute of Genetics at MENDELU.
The life cycle of Xcc begins on the surface of leaves, where the bacteria are found epiphytically. Natural entry into the plant occurs under conditions of high air humidity and temperature, when water droplets form on the edges of the leaf blades in the form of so-called guttation. “These droplets are formed by the excretion of excess water through the vascular system, but the plant is able to draw them back into the tissues. If bacteria are also present in the guttation drop, they enter the plant directly and begin to colonize its internal tissues. This initiates colonization of the vascular system, from where the pathogen spreads throughout the plant, including the tissues from which the seeds are formed. This is how infected seeds are created,” explained Pečenka. Secondarily, bacteria also spread in the field by other means – through injuries, pests, or rain splashes.
In addition to seed testing, the scientific team is also involved in the development of plant protection products based on advanced nanomaterials and monitoring their effects. The aim is to verify the effectiveness of the products against various pathogens and at the same time assess their environmental impact and harmfulness to the plants themselves. “To do this, we use plant gene expression analysis, which allows us to assess their response to both the presence of the pathogen and the tested product,” said the scientist.
The scientific team is collaborating with the Institute of Chemistry and Biochemistry of the Faculty of Agronomy on the development of protective products. These are mainly products based on nanomaterials, among which compounds of copper, graphene, silver, zinc, and silicon are used in particular. “Nanomaterials can penetrate the cell structure, so even a small amount is sufficient to achieve effective protection. This also means less impact on the environment,” explained Pečenka. Phenolic compounds, which occur naturally in medicinal and aromatic plants, are also used in experimental testing.
For more information, please contact: Ing. Jakub Pečenka, Ph.D., +420 608 111 498, jakub.pecenka@mendelu.cz, Mendeleum – Institute of Genetics, Faculty of Horticulture and Landscape Engineering, Mendel University