Cytological Studies in Endangered Phlomoides superba (Royle ex Benth.) Kamelin & Makhm.

Karyotype data, male meiosis and pollen fertility of endangered Phlomoides superba (Royle ex Benth.) Kamelin & Makhm., a plant of much medicinal, veterinary and ornamental value was studied. This study is the first report of karyotype and detailed male meiosis in the species. The species exist at the diploid level with 2n= 22 chromosomes. The cells were stained with acetocarmine and a standard squash technique was followed to study karyotype and male meiosis in the species. The chromosomes size shows a gradual decrease from 5.25 to 3.42 mu m with karyotype formula 2n=16m+6sm. P. superba shows an abnormal meiotic course with anomalies such as early and late disjunction, chromatin stickiness, formation of laggards, chromatin bridges, etc. affecting approximately 17.78% of the total PMCs undergoing the process of reduction division. However, high pollen fertility was seen despite such abnormalities.

Automated summary

This study is the first to report the karyotype and detailed male meiosis of the endangered plant species Phlomoides superba. The species is diploid with 22 chromosomes. Staining and squash techniques were used to study the karyotype and male meiosis. The chromosomes gradually decrease in size from 5.25 to 3.42 μm, with a karyotype formula of 2n=16m+6sm. The species exhibits abnormal meiotic processes, including disjunction issues, chromatin stickiness, formation of laggards and chromatin bridges, affecting approximately 17.78% of the total PMCs undergoing reduction division. Despite these abnormalities, the species showed high pollen fertility.