Nuclear Polymorphism Induced Genomic Instability in Cluster Bean [<i>Cyamopsis tetragonoloba</i> (L.) Taub.] (Fabaceae)

Abstract

Several environmental and mutagenic factors lead to induce nuclear polymorphism like micronuclei (MN) and nuclear buds. MN are the disintegrated partitioned nuclear or chromosomal fragment. Their occurrence is indicator of genomic instability or chromosomal turmoil. Combined mutagenic treatment of gamma rays and ethyl methane sulphonate (EMS) was experienced to induce formation of MN and nuclear buds in cluster bean [Cyamopsis tetragonoloba (L.) Taub]. A considerable proportion of microcells was also encountered that display future fate of micronuclei in the cell. A peculiar correlation with this nuclear polymorphism was experienced on the presence of bridges and laggards at anaphase I and II stages. Frequency of bridges and laggards were collinear to the combined mutagenic action. Pollen viability was also examined through pollen fertility percentage to inculcate effects of the nuclear incineration on the viability of pollen and the results depicted a dose dependent decline in pollen fertility.

First record of nucleus migration in premeiotic antherial cells of Saccharum spontaneum L. (Poaceae)

“…The uniformity in the size of uninucleate, binucleate and multinucleate cells in the presently studied grass suggests that only nuclei pass through cytoplasmic channels. Unlike this, cytomixis involves the transfer of both chromatin/ chromosome(s) along with cytoplasm as well as other cell organelles through cytomictic channels (Risueno et al 1969, Romanov and Orlova 1971, Mursalimov and Deineko 2011, Kumar and Choudhary 2016, Kumar and Singh 2020. This becomes apparent from the increase in the size of cytomictic products/ recipient cells, as has also been recorded by Sarbhoy (1980) and Singh et al (1989Singh et al ( , 1990.…”

“…Cytomixis involves chromatin transfer between proximate cells (Kamra 1960, Omara 1976, Belluci et al 2003, Singhal et al 2009, Himshikha et al 2010, Rana et al 2013, Bhat et al 2017, Mandal and Nandi 2017. Owing to this unique feature, it is also called as the phenomenon of intercellular chromatin transmigration (Kumar and Naseem 2013, Kumar and Choudhary 2016, Dwivedi and Kumar 2018, Khan et al 2018, Kumar and Singh 2020. Akin to cytomixis, nucleus migration requires the passage of a whole nucleus from donor cell to recipient cell (Gottschalk 1970, Patra et al 1987.…”

History and New Developments on the 90th Anniversary of Cytologia: On the Occasion of the Publication of “Dawn of Modern Wheat Genetics”

“…Edible grains from other plant families, such as buckwheat (Polygonaceae) (Gupta et al 2018), quinoa (Amaranthaceae), chia (Lamiaceae), and sesame (Pedaliaceae) (Das et al 2018) are referred to as pseudocereals. In addition to these plants, a large number of papers on legumes have been published in Cytologia, indicating the diversity of food available in India (Ghosh et al 2017, Chaudhary and Kumar 2017, Gosavi et al 2017, Kumar and Singh 2018, Egypt (Siddiqui et al 2018), and Mexico (Tapia-Pastrana et al 2018). The 90-year history of Cytologia shows that karyotype analysis is an excellent tool for diversity research.…”