B chromosome Maize 8 Maize native races 8 Poaceae 8 Zea mays 8 Zea mays ssp. mays 8 B transmission rate control 4 DNA content 4 Genome size 4 Holokinetic chromosomes 4 Abnormal Karyotype 2 Animals 2 Autosomal fusion 2 Chiasma frequency 2 Chromosome Banding 2 Chromosomes, Insect 2 Hemiptera 2 Heteroptera 2 Male 2 Mitosis 2 Reduviidae 2 Ring bivalents 2 Spermatogonia 2 Triatoma 2 Triatoma infestans 2 Univalents 2 X chromosome 2 Y chromosome 2 anaphase 2 article 2