Meiotic studies and chromosome data are imperative in order to have an overall germplasm evaluation of a taxon. In the present effort, the meiotic study is carried out in 48 populations belonging to 26 species of Lamiaceae collected from their natural habitats in Kashmir Himalaya, which forms an important part of Northwest Himalaya. Chromosome counts in the five species viz. Dracocephalum nutans (2n = 10), Lycopus europaeus (2n = 22), Marrubium vulgare (2n = 54), Nepeta nervosa (2n = 18) and Salvia sclarea (2n = 22) are first time reported from India. Besides, 17 species are cytologically evaluated for the first time from the study area-Kashmir Himalaya. In Marrubium vulgare, hexaploid cytotype (2n = 6 × =54) is reported for the first time. Also, diploid and tetraploid cytomorphovariants are observed in Calamintha vulgaris (2n = 20, 40), Elsholtzia ciliata (2n = 16, 32) and Mentha longifolia (2n = 20, 40). Various meiotic abnormalities like chromatin stickiness, cytomixis, nonsynchronous disjunction, laggards, chromatin bridges, etc. leading to pollen abnormalities have been documented for the first time in some species. The worldwide status of chromosome number data in each genus is presented.

Summary Failure of chromosome pairing was observed in all the presently investigated natural populations of Erigeron karvinskianus (2nϭ36). All 4 populations were observed with a different range of univalents besides bivalents at diakinesis and metaphase I. The presence of univalents bound with various other meiotic irregularities, such as laggards and chromatin bridges, which further lead to abnormal microsporogenesis. Pollen sterility was found to be high.

No abstract

SummaryThe present investigations have been made on 37 wild species including 76 accessions in 29 genera covering 3 families-Acanthaceae, Lamiaceae and Scrophulariaceae of the Bicarpellatae series of subclass gamopetalae. Chromosome numbers and detailed meiotic course, along with pollen fertility, have been studied for each species on its accession basis. New reports are recorded as B-chromosomes: Ajuga bracteosa (n=32+0-2B), Calamintha clinopodium (n=18+ 0-1B) and Hemigraphis latebrosa (n=12+0-2B) and Veronica anagallis-aquatica (n=18+2B); varied chromosome counts: Calamintha clinopodium (n=18), Hemigraphis latebrosa (n=12), Justicia diffusa (n=16) and Lindenbergia indica (n=25); euploid cytotypes: Lepidagathis hyalina (n=30) and Veronica persica (n=7). Two species, Veronica persica (n=7, 14) and Veronica anagallis-aquatica (n=18+2B), have been counted for the first time in India. A comparison of morphological characters in the above listed interesting taxa has been made.

No abstract