Five species of Ranunculus such as R. brotherusii, R. sieboldii, R. chinensis and R. silerifolius were karyologically studied especially with respect to speciation. Ranunculus brotherusii had the karyotype of 32 small-sized chromosomes (x=8). Ranunculus sieboldii had two different cytotypes such as 2n=48 and 2n=64. The 2n=48 karyotypes of the species from Mainland China were similar to each other and were identical to the 2n=48 karyotype from the Japanese Archipelago. The 2n=48 karyotype consisted of two different chromosomal groups: One chromosomal group comprising 32 and the other chromosomal group comprising 16 chromosomes. The 2n=64 karyotype might be produced by the fertilization of a normal gamete and an unreduced gamete. The karyotypes of R. sieboldii evidenced that the hybridization might play an important role of speciation. Ranunculus chinensis had a single and stable karyotype with 2n=16 under a wide geographical distribution across Mainland China and the Japanese Archipelago. In R. silerifolius specimens from the Mainland China, two different karyotypes such as Mugi and Otaru-C were identified. The Mugi cytotype was widely distributed across Mainland China and the Japanese Archipelago. The new karyotype, Otaru-C, was proposed in specimens from Mainland China. Polymorphism of the cytotype in R. silerifolius in the Japanese Archipelago was pointed out as an example of sympatric speciation.

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Karyomorophology at the resting nuclei, mitotic prophase and metaphase chromosomes in three species of Dracocepharum were studied. They had commonly the resting nuclei of the complex chromocenter type, the mitotic prophase chromosomes of the proximal type, and the mitotic metaphase chromosomes had 2n=12 for D. peregrinum, 2n=10 for D. nutans and 2n=24 for D. origanoides. These chromosome numbers were verified with the previous reports. The karyotype formula of three species had 2n=12=8m+4sm for D. peregrinum, 2n=10=8m+2sm for D. nutans and 2n=24=14m+10sm for D. origanoides, and chromosome sizes for D. peregrinum is a little smaller one compare with D. nutans and D. origanoides.

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A carnivorous plant lineage including the Droseraceae and its closely related family Drosophyllaceae shows wide range of chromosome size or genome size, whereas all other carnivorous families possess rather small in the genomes sizes. This study gives an overview of the genome size diversity in carnivorous plant families, and evolutional trend of chromosome differentiation especially in the Doroseraceae.

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To increase crop yield and soil fertility, crop producers use agricultural chemicals and artificial fertilizers. As a result plants become prone to fertilizer and soil infertility increases. A substitute to inorganic fertilizer could be biofertilizer. Biofertilizer is very beneficial for plants as it promotes growth and yield of plants without causing any ecological imbalance. The present investigation has been carried out to access the cytological effects of fertilizer urea and biofertilizer agrozyme on root tips of Trigonella foenum graecum L. It has been found that fertilizer turns out to be more chromotoxic and mito-inhibitory at higher doses in comparision to biofertilizer. High concentrations caused gradual decrease in mitotic index in case of fertilizer while in case of biofertilizer mitotic index is increased parallel to the increasing doses. Various chromosomal abnormalities were also observed at high concentration. In case of biofertilizer the abnormalities were lesser in comparison to fertilizer. The treated system showed various cytological irregularities viz. stickiness, precocious movement, unorientation, bridges, and forward movement. Although both share common range of aberrations but stickiness is predominant among them.

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The present investigation involves the meiotic studies on three populations of Cyathula capitata Moq. (family Amaranthaceae) from west Himalaya. All the three populations uniformly revealed chromosome count of 2n=34 which is the first ever report for the species. Male meiosis was abnormal in all the populations characterized by occurrence of chromatin stickiness, laggards and bridges leading to abnormal microsporogenesis. The two populations showed the phenomenon of cytomixis resulting into heterogenous sized pollen grains.

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