Spindle irregularities, chromatin transfer, and chromatin stickiness during male meiosis in Anemone tetrasepala (Ranunculaceae)

Detailed cytological investigations performed in Anemone tetrasepala Royle from the Pangi Valley revealed the presence of various irregularities (spindle irregularities, chromatin transfer, chromatin stickiness, and nonsynchronous condensation of chromatin material) for the first time in the species that existed at diploid level (2n = 14). | Turkish Journal of Botany Research Article Turk J Bot (2013) 37: 167-176 © TÜBİTAK doi: Spindle irregularities, chromatin transfer, and chromatin stickiness during male meiosis in Anemone tetrasepala (Ranunculaceae) Pawan Kumar RANA, Puneet KUMAR and Vijay Kumar SINGHAL* Department of Botany, Punjabi University, Patiala, 147002, Punjab, India Received: Accepted: Published Online: Printed: Abstract: Detailed cytological investigations performed in Anemone tetrasepala Royle from the Pangi Valley revealed the presence of various irregularities (spindle irregularities, chromatin transfer, chromatin stickiness, and nonsynchronous condensation of chromatin material) for the first time in the species that existed at diploid level (2n = 14). Spindle irregularities resulted in dyads, triads, polyads, and micronuclei in sporads during microsporogenesis and variable sized pollen grains and reduced fertility in pollen grains (). Direct fusion among proximate meiocytes resulted in the formation of syncyte pollen mother cells. Such syncytes yielded jumbo-sized pollen grains that were surely of unreduced nature in their genetic constitution. Due to severe chromosome stickiness, chromosome separation during anaphases was also affected. Another interesting observation was the nonsynchronous condensation of 1–2 chromosomes during anaphase-I. This paper discusses the consequences of chromosomal and spindle irregularities on the course of meiosis and microsporogenesis and ultimately on the end products. Key words: Anemone tetrasepala, nonsynchronous condensation, intra-microsporal, jumbo pollen grains, meiotic course, Pangi Valley, syncytes 1. Introduction All living organisms, irrespective of their complex organisation, meiotically reduce their chromosome number to generate haploid gametes at the start of sexual reproduction, which compensate for fertilisation and .

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