Impact of cytomixis on meiosis, pollen viability and pollen size in wild populations of Himalayan poppy (Meconopsis aculeata Royle). J Biosci

Department of Botany, Punjabi University, Patiala, India.
Journal of Biosciences (Impact Factor: 2.06). 10/2008; 33(3):371-80. DOI: 10.1007/s12038-008-0057-0
Source: PubMed


We report the occurrence of cytomixis in wild populations of Himalayan poppy (Meconopsis aculeata Royle),which is considered to be an important and threatened medicinal plant growing in the high hills of the Himalayas. The impact of cytomixis on meiotic behaviour, reduced pollen viability and heterogeneous-sized pollen grains was also studied. Cytological studies in the seven wild populations from the high hills of Himachal Pradesh revealed that all the Himalayan populations exist uniformly at the tetraploid level (2n=56) on x=14. The phenomenon of chromatin transfer among the proximate pollen mother cells (PMCs) in six populations caused various meiotic abnormalities. Chromatin transfer also resulted in the formation of coenocytes, aneuploid, polyploid and anucleated PMCs. Among individuals that showed chromatin transfer, chromosome stickiness and interbivalent connections were frequently observed in some PMCs. The phenomenon of cytomixis in the species seems to be directly under genetic control; it affects the meiotic course considerably and results in reduced pollen viability.

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Available from: Puneet Kumar, Ph.D.,
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    • "The migration of chromatin from one cell to another directly interferes with its function and development. The increase or reduction of DNA content in PMCs may cause problems in microsporogenesis and consequently failure in the formation of balanced gametes (Bellucci et al. 2003; Singhal and Kumar 2008; Ferreira et al. 2009; Kumar et al. 2010). The most common abnormalities observed were condensed micronucleus, desynapsis, chromosome stickiness, incorrect pairing, unequal segregation, laggard chromosomes, precocious migration, and chromosome bridge (Lattoo et al. 2006) as was observed in a tetraploid accession of L. alba investigated here (Table 1; Fig. 1g). "

    Plant Systematics and Evolution 09/2015; DOI:10.1007/s00606-015-1249-3 · 1.42 Impact Factor
    • "Cytomixis was observed at certain meiotic phases, or in all stages (de Souza and Paytomixis was observed at certain meiotic phases, or in all stages (de Souza and Pawas observed at certain meiotic phases, or in all stages (de Souza and Pas observed at certain meiotic phases, or in all stages (de Souza and Paobserved at certain meiotic phases, or in all stages (de Souza and Pacertain meiotic phases, or in all stages (de Souza and Paor in all stages (de Souza and Pan all stages (de Souza and Pastages (de Souza and Pastages (de Souza and Paand Pa- Pagliarini , 1997; Pierozzi and Benatti, 1998; Malallah and Attia, 2003), more frequently in the first division (Bellucci et al., 2003; Lattoo et al., 2006). The transfer of chromatin material during microsporogenesis was considered to cause various meiosis abnormalities, reduced pollen viability and heterogeneous-sized pollen grains (Singhal and Kumar, 2008a). Here, the occurrence of cytomixis in Pinellia only during first division with low frequency might also contribute to some of the meiotic abnormalities observed, such as univalents, chromosome laggards and bridges, micronuclei, low pollen stainability, and poor seed-set, because the transfer of different amounts of chromatin resulted in the unbalanced complements of the PMCs involved. "

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    • "Knight et al. 2010), cytology (e.g. Singhal & Kumar 2008) or ploidy level (e.g. Jacob & Pierret 2000; Pradeep & Jambhale 2000). "
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