Karyomorphological studies in Mucuna of India

Abstract

Mucuna Adans. is a large genus with more than 150 species of annual and perennial legumes of pantropical distribution. Despite considerable economic importance of some of its species, almost no work has been done on their cytogenetic characterization in any part of World. In this paper, we have presented a fi rst report on karyomorphological analysis in four Indian species viz., Mucuna atropurpurea, Mucuna monosperma, Mucuna nigricans and Mucuna pruriens bringing out diploid number for M. atropurpurea and karyotypic formula for all the four species. Root tips were treated with 0.002 M 8-hydroxyquinoline and temporary preparations were made after squash in aceto-carmine. Karyomorphological description for each of the species has been detailed taking into account the following features: chromosome number, total length and relative length, arm ratio of each chromosome, haploid set length and degree of asymmetry. Mitotic metaphases in all the species showed 2n=22 chromosomes. Mucuna nigricans showed two pairs of sat-chromosomes. None of the species, however, revealed identical karyotypic formula indicating occurrence of rearrangements. The haploid set length of annual M. pruriens was found to be reduced in size when compared to perennial species pointing its evolution from the latter.

Karyotype studies in <i>Mucuna macrocarpa</i> Wall and <i>Mucuna sanjappae</i> Aitawade et Yadav (Fabaceae) from India

“…Mucuna has very low % of polyploidy. Earlier workers reported diploid chromosome number of 2n = 22 in M. pruriens, (Bairiganjan andPatnaik 1989), M. monosperma (Thuvan 1975), in M. atropurpurea (Jaheer and Sathyanarayana 2010) and M. nigricans (Kumari and Bir 1990) and in our present cytological investigation for diploid chromosome number of M. sanjappae and M. macrocarpa 2n = 22 was observed. For the determination of the THCL of papilionaceous legume the chromosome size is more important and is the real determinant rather than chromosome number Bir 1985, 1989).…”

Role of genetic resources and molecular markers inMucuna pruriens(L.) DC improvement

“…Chromosomal studies even in genus Mucuna suggests x = 11 as the base number even though x = 14 is reported in Mucuna gigantea and Mucuna benettii (Sastrapradja et al, 1974; Jaheer and Sathyanarayana, 2010). So far, karyotype descriptions are available only for Mucuna atropurpurea, Mucuna monosperma, Mucuna nigricans and M. pruriens (Agostini et al , 2009; Jaheer and Sathyanarayana, 2010). Recently our group completed karyotyping of two other Indian species viz., Mucuna sempervirens, Mucuna bracteata .…”

“…Conservation of basic chromosome number x = 11 is one of the prevailing features in Phaseoloid legumes. Chromosomal studies even in genus Mucuna suggests x = 11 as the base number even though x = 14 is reported in Mucuna gigantea and Mucuna benettii (Sastrapradja et al, 1974;Jaheer and Sathyanarayana, 2010). So far, karyotype descriptions are available only for Mucuna atropurpurea, Mucuna monosperma, Mucuna nigricans and M. pruriens (Agostini et al, 2009;Jaheer and Sathyanarayana, 2010).…”

Genetic characterization of a red colour morph of Euphorbia esula subsp. esula (Euphorbiaceae) in the floodplains of the Saône (Eastern France)

“…temperature. Root tips (about five mm in length) of three-to four-day old seedlings were 10 a.m. Root tips were treated and stained with aceto-carmine and ferri-acetate, following the procedure ofJaheer et al (2010). Mitotic metaphase figures were examined by light microscopy at 15 x 100 magnification (Leitz Dialux 20, Munich, Germany).…”