Cell division study in ‘pollen mother cells’ and ‘pollen grains’ of in vivo and ex vitro plants in Drimiopsis botryoides

Abstract

The various normal and abnormal stages of meiosis and pollen mitosis of Drimiopsis botryoides are described, and a comparison between naturally propagated in vivo and tissue culture derived ex vitro plants in respect to their cytological behaviour presented. We also describe the floral morphology and investigate the relationship between the floral developmental stages and the progression of microgametogenesis. In total, 33 bivalents are observed in diakinesis, which indicate the diploid number 2n = 66 and this number is cross-checked by a haploid set of n = 33 chromosomes in pollen mitosis. Only 6.8% and 4.9% meiotic abnormalities were recorded on in vivo and ex vitro plants, respectively, which led to the formation of non-viable pollen. Finally, the microspores have to develop into tri-cellular male gametophyte. Only 0.2% pollen grains are found with a micro-nucleus. Though the higher pollen viability was recorded on both in vivo (89.3 ± 4.1%) and ex vitro (92.1 ± 4.6%) plants, but surprisingly the pollen germination rate is extremely low with 13.6 ± 1.74% and 21.3 ± 1.55%, respectively. The present study obviously enriches the cytological database of D. botryoides and may help future research on androgenesis and genetic improvement.

Keywords:

• floral morphology
• meiotic abnormalities
• microgametogenesis
• microsporogenesis
• pollen mitosis
• tissue culture derived plants

Acknowledgements

SMH acknowledges the ‘Ministry of Minority Affairs’ and the ‘University Grant Commission’ (UGC) of India for providing a ‘Maulana Azad National Fellowship’. Both the authors are thankful to Swami Kamalasthananda, Principal, RKMCV College, Rahara, Kolkata (India), for the facilities provided for the present study.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the University Grant Commission (UGC) of India under grant number F1-17.1/2010/MANF-MUS-WES-5180’.