Cytomixis—a unique phenomenon in animal and plant

Abstract

Cytomixis is reported to be a uniform phenomenon in the context of fertilization during spermatogenesis of animals and in some lower groups of plants where oogamous reproduction prevails. However, the phenomenon is versatile in flowering taxa as it lacks uniformity in occurrences, causes, formation of intercellular bridges, involvement of number of cells in a cluster, evolutionary significance among others. A review on cytomixis is conducted with an objective that it may offer a scope to unravel some of the ambiguities associated with it and provide further information on cell, reproductive, structural and evolutionary biology.

Morphological and Ecological Adaptations, and Cytological Studies in <i>Astragalus rhizanthus</i> Royle ex Benth. (Papilionaceae), an Endemic to Himalayas

“…Similar results regarding the high pollen fertility in plants depicting cytomixis were reported in Dactylis (Falistocco et al 1995). As individuals with and without cytomixis are found to grow in the same environmental conditions, cytomixis in A. rhizanthus seems to be a natural process of intercellular interaction under direct genetic control (Omara 1976, De and Sharma 1983, Singhal and Gill 1985, Lattoo et al 2006Singhal and Kumar 2008a, Kumar 2010, Kravets 2012, Mandal et al 2013. …”

Identification of new cytotypes of Valeriana jatamansi Jones, 1970 (Valerianaceae) from North-Western Himalayan region of India

“…Some others considered it to be of great importance as the most probable consequence of cytomixis is the formation of hypo-, hyperploid and enucleated PMCs, aberrant microspore tetrads and pollen sterility (Sheidai and Fadaei 2005, Jeelani et al 2011). Cytomixis results in the production of unreduced gametes in several angiosperms and leads to the production of aneuploid or polyploids plants (Fadaei et al 2010, Mandal et al 2013). The formation of unreduced gametes is of evolutionary significance in a way that it can lead to the production of plants with higher ploidy level through polyploidization (Villeux 1985).…”

Cytomorphology, Geographical Distribution and Ethnobotany of Genus <i>Oxalis</i> Linn. from Western Himalaya (India)

“…The populations of tetrapliod cytotype (2n=24) of the same species lack meiotic abnormalities and exhibited high pollen fertility (85-93%). Previously, cytomixis has been reported to be more common in diploid populations than polyploids (Mandal et al 2013). However, in many other angiosperms, normal meiosis in diploid cytotypes and abnormal in polyploid cytotypes has also been reported by Sheidai and Attaei (2005) and Rani et al (2014).…”