One of the basic for the successful production of hybrid seeds is ensuring the genetic homogenity of the parental lines and their hybrids. This can be assessed using laboratory methods, such as protein markers, isozymes, and molecular markers, as well as field tests. MALDI-TOF MS (matrix-assisted laser desorption/ionization time-of-flight mass spectrometry) is particularly suitable for examining the genetic homogenity of seeds, as it allows obtaining a unique “protein fingerprint” for each sample based on the detected m/z values and peak intensities. Proteins appear as characteristic peaks in the mass spectrum, and their presence or absence can be used to infer the uniformity of the samples. The advantage of MALDI-TOF lies in its ability to rapidly and reliably detect proteins, even in complex samples, while measurement parameters – relative intensity, absolute intensity, signal-to-noise ratio, resolution, and peak area – allow an objective evaluation of spectrum quality. In homogeneous seed samples, spectra display nearly identical peaks and intensities, whereas heterogeneous samples exhibit differing peak patterns. Thus, this technique is fast, sensitive, and reproducible, enabling the monitoring of marker proteins, comparison of spectra, and precise determination of genetic homogenity.