B chromosomes are supernumerary dispensable chromosomes. They have a non-Mendelian way of inheritance and individuals from a same population may or may not carry B chromosomes. Their number is varying due to the non-disjunction during the meiosis. It is commonly accepted that B chromosomes have evolved from the normal set of chromosomes (so called A chromosomes). Nevertheless, a few is known about their structure and the elements behind the non-disjunction and the drive mechanism. Tribe Andropogoneae comprises several species containing B chromosomes. The question arises, whether the B chromosomes have appeared in their common ancestor or emerged in several independent events. To shed light on their evolution, we will sequence and analyse B chromosomes from two Andropogoneae species and compare them with the maize B chromosome in order to investigate the emergence of the B chromosomes in this tribe.