Cyto-Molecular Characterization of Three <i>Tacca</i> Species from Bangladesh

Abstract

Summary Three species of Tacca J. R. & G. Forst., namely T. plantaginea, T. chantrieri and T. integrifolia, were investigated cytogenetically and at the molecular level to solve their taxonomic rank. The diploid chromosome number 2n=28 was found in T. plantaginea and T. integrifolia whereas 2n=22 was found in T. chantrieri. This is probably the first report on the diploid chromosome number of T. plantaginea and T. chantrieri around the world. The three species differed in respect of centromeric formulae such as 22m+6sm in T. plantaginea, 18m+4sm in T. chantrieri and 28m in T. integrifolia. In addition to regular 2n=22 chromosomes, four to eight small chromosomes were found in some cells of T. chantrieri suggesting the probable occurrence of B-chromosome. In T. integrifolia, a pair of satellites was found on the short arm, one in each member of pair VI, after orcein and CMA staining but not in DAPI, revealing the GC-rich nature. A wide range of CMA-and DAPI-positive bands was found in the metaphase chromosomes of the three species. DAPIfluoresced chromosomes were frequent in these three species. Six primer combinations were applied for RAPD analysis in the three species of Tacca to find out their genomic relationship. The three species showed some unique bands useful as markers for each species. Conventional and fluorescent karyotype together with RAPD fingerprinting indicated that T. integrifolia is distantly related to T. plantaginea and T. chantrieri. Therefore, the compilation of the above cytological and molecular information will be very useful for authentic identification of the three Tacca species. This genetic information will help in the proper conservation of and to make patent for the three threatened Tacca species found in Bangladesh.

Karyotype and RAPD Diversity in Four Varieties of <i>Gossypium hirsutum</i> L.

“…This banding nature makes these chromosomes different from the other. The probable reason for entirely fluoresced chromosomes was i) either these chromosomes were completely AT-rich by nature or ii) due to successive duplication of AT-rich repeats (Hossain et al 2016, Hossen et al 2016. Entirely DAPIbanded chromosomes were also reported earlier by Sultana and Alam (2016a).…”

Karyotype and Chromosome Behavior Analyses in Three Regions of the Indomalayan Realm

“…In one recent study (Hossen et al 2016), plants that commonly grow in urban areas of Dhaka, such as Colocasia esculenta (L.) Schott (Nahar and Alam 2016a) and Ipomoea aquatic (Nahar and Alam 2016b), were used to observe the effects of effluents from the textile, pesticide, tannery, ceramic, and pharmaceutical industries on chromosomal and DNA levels. These plants also included Tacca spp., which are used as folk medicines by different tribal peoples and are now under severe threat in Bangladesh due to rapid industrialization, urbanization, deforestation, and misuse of land.…”

Callus induction of Tacca integrifolia Ker Gawl using stem nodal segment

“…T. integrifolia has several local names as 'Belimbing Tanah', 'Keladi Murai' and 'Janggut Adam' and this species very closely resembles Tacca chantrieri but differs only in petiolar-like sheath in the bract (Misrol et al, 2015;Baruah et al, 2015). The potential traditional medicine for this species was being practised by the Thai and Myanmar folk people to fight against the pest, control blood pressure, improve sexual function in humans, treatment for skin diseases and various kinds of cancers (Misrol et al, 2015;Hossen et al, 2016;Shwe et al, 2010).…”