B chromosome transmission in Plantago 375 B chromosome in Plantago lagopus Linnaeus, 1753 shows preferential transmission and accumulation through unusual processes Manoj K. Dhar 1 , Gurmeet Kour 1 , Sanjana Kaul 1 1 School of Biotechnology, University of Jammu, Jammu-180006, INDIA Corresponding author: Manoj K. Dhar (manojkdhar@redifmail.com) Academic editor: Ilya Kirov  |  Received 12 January 2017  |  Accepted 13 March 2017  |  Published 22 May 2017 http://zoobank.org/1605026B-DDE2-4D98-BC62-DBA79D1330F9 Citation: Dhar MK, Kour G, Kaul S (2017) B chromosome in Plantago lagopus Linnaeus, 1753 shows preferential transmission and accumulation through unusual processes. Comparative Cytogenetics 11(2): 375–392. https://doi. org/10.3897/CompCytogen.v11i2.11779 Abstract Plantago lagopus is a diploid (2n = 2x =12) weed belonging to family Plantaginaceae. We reported a novel B chromosome in this species composed of 5S and 45S ribosomal DNA and other repetitive elements. In the present work, presence of B chromosome(s) was confrmed through FISH on root tip and pollen mother cells. Several experiments were done to determine the transmission of B chromosome through male and female sex tracks. Progenies derived from the reciprocal crosses between plants with (1B) and without (0B) B chromosomes were studied. Te frequency of B chromosome bearing plants was signif- cantly higher than expected, in the progeny of 1B female × 0B male. Tus, the B chromosome seems to have preferential transmission through the female sex track, which may be due to meiotic drive. One of the most intriguing aspects of the present study was the recovery of plants having more chromosomes than the standard complement of 12 chromosomes. Such plants were isolated from the progenies of B chromo- some carrying plants. Te origin of these plants can be explained on the basis of a two step process; for- mation of unreduced gametes in 1B plants and fusion of unreduced gametes with the normal gametes or other unreduced gametes. Several molecular techniques were used which unequivocally confrmed similar genetic constitution of 1B (parent) and plants with higher number of chromosomes. Keywords Accumulation, drive, FISH, Molecular markers, Unreduced gametes CompCytogen 11(2): 375–392 (2017) doi: 10.3897/CompCytogen.v11i2.11779 http://compcytogen.pensoft.net Copyright Manoj K. Dhar et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. RESEARCH ARTICLE COMPARATIVE Cytogenetics International Journal of Plant & Animal Cytogenetics, Karyosystematics, and Molecular Systematics A peer-reviewed open-access journal