Four populations of Physalis angulata L. were meiotically worked out from different regions of Rajasthan, India. Two cytotypes were reported here, i.e., n=12 and n=24. The diploid cytotype (n=12) was reported here for the first time from India. Two populations depicted (n=12) diploid level of ploidy and the other two populations reveled tetraploid level (n=24) of ploidy. Tetraploid cytotype (n=24) has already been reported by many workers from India and even outside of India but the diploid cytotype (n=12) was reported here for the first time in India. Course of meiosis was normal in diploid cytotype but the tetraploid cytoypes showed the presences of 0-3 quadrivalents at diakinesis and metaphase I.

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The present paper deals with the cytological sampling in 13 populations of four species such as Dracocephalum heterophyllum Benth., Micromeria biflora (L.) Hunds., Origanum vulgare L. and Scutellaria discolor Colebr. from the flora of Lahaul-Spiti and its adjoining areas of North West Indian Himalaya. The meiotic chromosome number of 2n=24 of D. heterophyllum was tetraploid (4x) report from the India for the first time, while chromosome number of 2n=48 of S. discolor (2n=48) was the first report of the tetraploid (4x) record to the world cytological database. Two species, namely, M. biflora (2n=30) and O. vulgare (2n=30) with diploid (2x) chromosome counts were cytologically reconfirmed to the Indian flora. Morphovariants were also reported in these two (i.e. M. biflora and O. vulgare) taxa. In studied genera nearly 33.33% of species in Dracocephalum L., 66.67% species in Micromeria Benth., nearly all the species in Origanum L. and 31.89% of species in Scutellaria L. are available with their cytological counts to the Indian flora.

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Chromosome variation of wild and cultivated Iris ensata Thunb. was investigated by the standard chromosome analysis and modern molecular cytogenetic analysis by using fluorescence in situ hybridization detecting 18S and 5S rDNA sites. In the standard chromosome analysis, the chromosome numbers of ten individuals studied were 2n=24, and 12 chromosomes were morphologically similar among the individuals. On the other hands, the sizes of 18S rDNA sites were varied among the individuals, though 18S and 5S rDNA sites were uniformly existed on six and two chromosome, respectively. The larger and smaller 18S rDNA sites were observed on a single chromosome, and these chromosomes were morphologically similar among individuals. These aspects suggested that the partial chromosome changes such as addition and deletion occurred on the fixed chromosome in I. ensata.

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Morpho-criteria, karyotype analysis, chromosome number and ploidy levels were studied for three mulberry varieties. Mysore local and RFS-₁₇₅ is diploid with 2n=28 and BC_2-59 is triploid with 2n=42 somatic chromosomes numbers respectively. Somatic chromosome length ranges from 1.29 m to 3.29 m where as arm ratio ranges from 0.59 to 1.00 m. Karyotypes of these taxa are symmetric. Only metacentric and submetacentric chromosomes are found in the somatic complement. Stomatal frequency is lesser in triploid variety when compared to diploid varieties.

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