Cytogenetical studies in the genus Cymbopogon spreng II. Meiotic studies in six species and their varieties

Vijeshwar Verma, S. N. Sobti
The genus Cymbopogon includes some economically very important aromatic grasses. The members of this genus are quite common in tropical and sub-tropical part of the eastern hemisphere. About 20 species are reported in India which are distributed in the regions having abundant rainfall (Bor 1953 , 1960 , Jagdish Chandra 1975 , Verma 1981 . Most of the species belonging to this genus show morphological diversity indicating the possibility due to gene exchange between the species. In order to
more » ... stand the basis of diversity and variability a detailed study of morphology, breeding system, karyotype and pairing behaviour of the chromosomes in the meiosis of six Indian species and their varieties was undertaken. Detailed karyological studies of the above species/varieties were reported earlier (Verma and Sobti 1982) . The present study deals with the aspects of morphology and male meiosis in the above species and varieties of genus Cymbopogon Material and methods The species and varieties investigated alongwith their chromosome numbers and places of collection are given in Table 1 . The above plants were collected from different places in India and are maintained in the experimental garden of RRL, Jammu. Observations on morphological characteristics of the plants were made in the field based on 5-10 plants in each species. To provide a visual impression of comparison of species, polygraphs were prepared with the help of twelve im portant characters (Fig. I) . For meiotic preparation squash method using aceto-carmine was followed. The slides were analysed invariably before making them permanent and photo graphs were taken also at the same time. Later the slides were made permanent by the usual method using DPX as the mountant (Darlington and La Cour 1958) . Results The six species of Cymbopogon alongwith their varieties included in the present investigation are well known, but detailed description with measurements of im portant diagnostic organs was lacking. Fig. 1 shows the comparative morphology of the species and varieties in the form of polygraphs. Out of the nine varieties of six Cymbopogon species examined 5 were diploids
doi:10.1508/cytologia.50.351 fatcat:roprgnlqebgwfcl5hcqh6on5v4