TY - JOUR AU - Andrada, Aldo Ruben AU - Páez, Valeria de los Ángeles AU - Caro, M.S. AU - Kumar, P. PY - 2019/12/23 Y2 - 2024/03/29 TI - Meiotic irregularities associated to cytomixis in Buddleja iresinoides (Griseb.) Hosseus. (Buddlejaceae) and Castilleja arvensis Schltdl. & Cham. (Orobanchaceae) JF - Caryologia JA - Caryologia VL - 72 IS - 4 SE - Articles DO - 10.13128/caryologia-298 UR - https://riviste.fupress.net/index.php/caryologia/article/view/298 SP - 41-50 AB - <p>The current paper analyzes the male meiotic behavior in wild populations of <em>Buddleja iresinoides </em>and <em>Castilleja arvensis </em>from Piedmont areas of the Northwest Region of Argentina. <em>Castilleja</em> <em>arvensis </em>showed tetraploid number of chromosome of 2<em>n </em>= 24. Our results are not in agreement with the previously reported base number <em>x </em>= 19 for <em>Buddleja </em>and the chromosome number <em>n </em>= 28 found for <em>B</em>. <em>iresinoides </em>is atypical in the genus. Around 7 % pollen mother cells were aneuploid as they showed meiotic chromosome count of n = 20-21 bivalents. Possible origin for such atypical chromosome number has been discussed in this paper. During the cytological studies we also came across pollen mother cells showing meiotic abnormalities such as cytomixis, chromatin stickiness and anaphase bridges with lagging chromatin. Consequently microsporogenesis was also irregular showing dyads and triads. However, the percentage of these irregularities during meiosis and microsporogenesis was not higher, and pollen fertility was not affected to a great extent. Cytomixis and other meiotic abnormalities in these species are reported here for the first time.</p> ER -