Cytomixis and Associated Abnormalities during Male Meiosis in Lindelofia longiflora var. falconeri (Boraginaceae)

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Detailed male meiotic studies were made in Lindelofia longiflora (Royle ex Benth.) Baill. var. falconeri (Cl.) Brand (Family: Boraginaceae) from the cold deserts of Pangi Valley, Chamba District (Himachal Pradesh) in India. The meiotic course in some of the individuals was observed to be highly abnormal which include cytomixis involving chromatin transfer among meiocytes, spindle irregularities, chromatin stickiness and mutlipolar PMCs, resulting in abnormal sporads as dyads, triads, polyads and tetrads with micronuclei. The products of such sporads result in high pollen sterility (77%) and variable-sized pollen grains. As a consequence of cytomixis, hyperploid (73.04%), hypoploid (18.59%) and enucleated PMCs (8.37%) are resulted. The enucleated PMCs may degenerate during the later stages of meiosis while hypo- and hyperploid PMCs yielded pollen grains of variable sizes and sterile pollen grains. The phenomenon of cytomixis and associated meiotic irregularities seem to have been caused due to low temperature stress conditions prevailing in the area.