Comparative cytological studies were carried out on Gilo and Shum cultivar groups of Solanum aethiopicum (scarlet eggplant) and their ancestor-Solanum anguivi, in order to elucidate the evolutionary relationships between them. Results indicated preferential pairing of chromosomes in S. anguivi and non-preferential pairing of chromosomes in Gilo and Shum cultivar groups of S. aethiopicum during early stages of meiosis. The low degree of pairing in Gilo and Shum cultivar groups of S. aethiopicum and higher percentage of chromosomal abnormalities (12.50 and 10.58% respectively showed cases of translocation heterozygotes and suggest that the two taxa have hybrid origin. Conversely, the high degree of pairing and very low percentage of chromosomal abnormalities (2.50%) tend to suggest that S. anguivi is more ancient than either the Gilo and Shum cultivar groups of S. aethiopicum. It had already been proved that the Gilo and Shum cultivar groups of S. aethiopicum together with the Kumba and Aculeatum groups originated from S. anguivi (Lester & Niakan, 1986). Also studies on external morphology and cytological studies have shown the Gilo cultivar group to be more complex morphologically and having higher percentage of chromosomal aberrations (12.50% as against 10.58% observed in Shum cultivar group). It is suggested that the Gilo cultivar group might have evolved from the Shum cultivar group through hybridization and selection, while the S. anguivi was already stabilized as their ancestor.

Comparative cytological study of Solanum aethiopicum Gilo group, Solanum aethiopicum Shum group and Solanum anguivi

Present paper deals with the cytological studies of monoecious and dioecious forms belonging to three Charophyte genera viz. Chara, Nitella and Tolypella. The taxonomic validity of sexual dimorphism has been discussed refuting the generalization of Wood and Imahori (1965).

Polyploidy in relation to sexual dimorphism in Charophyta.

Article de synthese sur la phylogenese et l'evolution des genres Chareae, Nitellae et Tolypella, validite du statut d'espece independante de Tolypella

A Karyological Approach to Phylogeny and Interrelationships of Charophyta

Mutagenicity of 1-Triacontanol was tested on Tolypella prolifera. On the basis of induced chromosomal and nuclear aberrations, mitotic index and the percentage of aberrated cells, mutagenic activities of Triacontanol were assessed. Application of Triacontanol in charophyte taxa has been recommended for chromosome analysis in place of polyploid inducing colchicine.

https://www.jstage.jst.go.jp/article/cytologia1929/54/1/54_1_183/_pdf

Mutagenicity of Triacontanol in Tolypella prolifera (Div. Charophyta)

Nitella has been observed to grow in different aquatic habitats during algal survey from various areas of Silchar and was taxonomically identified as Nitella mirabilis (O. Nordstedt ex J. Groves) R. D. Wood, 1965 (dioecious). The physico-chemical parameters of water were also analyzed. Using isolated and purified genomic DNA, RAPD band patterns were recorded by PCR amplification for molecular characterization of maacrophytic algae. The electrophoretic patterns were analyzed to provide diagnostic fingerprints for each sample based on RAPD markers. The DNA fingerprint produced consisted of identical RAPD patterns in all the tested samples collected from different localities.

Nitella mirabilis from Assam: Morphology and Molecular Characterization using RAPD markers

Cytotaxonomic studies in the genus Tolypella (T. nidjca var. glomerata (Desv. in Lois.) Leonh. em. R. D. W.) have been conducted for the first time from Indian subcontinent and a chromosome count of n=11 has been established in this taxon. The hybridized origin of 11chromosome number and the concept of three basic chromosome numbers for this genus as suggested by Sawa (1974) have been upheld. The phylogenetic status of Tolypella has also been discussed in detail.

https://www.jstage.jst.go.jp/article/cytologia1929/51/2/51_2_413/_pdf

S. K. Bhatnagar

Papers

The Genus Tolypella (Div. Charophyta) from Indian subcontinent―A cytotaxonomic approach

Mutagenic efficacies of triacontanol in Chara braunii Gm. (Charophyta) with reference to its application in chromosome analysis

Polyploidy in relation to sexual dimorphism in Charophyta.

A Karyological Approach to Phylogeny and Interrelationships of Charophyta

Mutagenicity of Triacontanol in Tolypella prolifera (Div. Charophyta)