Meiotic Studies, Pollen Fertility and Seed Set of <i>Actaea kashmiriana</i>, an Endemic Medicinal Plant Species of Kashmir Himalaya

Abstract

The present study reports the chromosome number and meiotic behavior including microsporogenesis of Actaea kashmiriana J. Compton and its relation with pollen fertility and seed set. The species showed a chromosome count of 2n=4x=32 and meiotic chromosomal irregularities such as chromatin stickiness, cytomixis, laggard formation, chromosomal bridges, micronuclei and polysporads. B-chromosomes were also observed in this species. Due to these meiotic irregularities, reduced pollen fertility was observed in the range of 85-87%, and the seed set was also significantly reduced to 67.16 to 70.45%.

Meiotic behavior and its implications on the reproductive success of Arnebia euchroma (Royle ex Benth.) I.M.Johnst. (Boraginaceae), an important medicinal plant of Trans-Himalaya

“…As a result of the chromatin material being transferred between PMCs, the irregularities associated with this transfer including chromosomes stickiness, sterility of pollen grains (Páez et al 2021) was observed. This phenomenon functions as an additional potential genetic recombination mechanism (Mursalimov and Deineko 2017;Rashid et al 2022b) and is a natural meiotic aberration that may have evolutionary importance (Singhal et al 2018). The cytoplasmic channels and chromatin migration has also been reported in meiocytes of Arnebia hispidissima (Baquar and Husain., 1969).…”

“…The sticky chromatin in various flowering plants have been attributed to gene mutation that disrupts proteins which in normal circumstances helps the chromosomes stay apart and prevents adherence (Tantary et al 2021). However, the low temperature and high UV exposure in the alpine habitats (Rashid et al 2022b) may be responsible for the observed chromosomal stickiness in the Arnebia euchroma. Chromosomal stickiness and the ensuing lack of chromosomal segregation at anaphase I can be suspected as the cause of meiotic abnormalities in the current investigation as seen in case of other studies (Masoud et al 2010; Sin- gh et al 2022).…”