IDENTIFICATION OF SOME HIBISCUS GERMPLASM THROUGH NUMERICAL ANALYSIS

Numerical analyses of 68 morphological characters of 12 varieties/forms belonging to four species of Hibiscus were carried out by calculating Sørensens and Sneath and Sokal similarity coefficients followed by cluster analysis and construction of dendrograms for visual appreciation of taxonomic relationship within this family. The Sørensens similarity coefficient varied between 0.211 and 0.919 and Sneath and Sokal similarity coefficient ranged between 0.142 and 0.890, indicating much variation between the species. Introduction The genus Hibiscus Medik. of family Malvaceae exhibits considerable taxonomic complexity. In Bangladesh, Hibiscus cannabinus L. (Deccan hemp or Kenaf) and H. sabdariffa L. (Rosella or Mesta), are cultivated and H. acetosella L. and H. radiatus L. are wild. In recent years H. cannabinus and H. sabdariffa are getting much attention and grown commercially for paper-pulp production in many countries (Andrew and Piters 1980, Nieschlag et al. 1960). In Bangladesh, paper and pulp mills have recently introduced Kenaf (H. cannabinus) along with jute whole stem as raw materials for paper and pulp making (Anonymous 1993). This new use has led to investigate about the component characters contributing to biomass production of the above four species. The fibre of jute (Corchorus capsularis and C. olitorius), Kenaf (H. cannabinus) and Mesta (H. sabdariffa) are considered as economic yield for textile purpose, while air dry whole stem is considered as biomass in paper-pulp industries (Kalder 1991). Despite the high socio-economic significance no major breakthrough has been achieved in research relating to these above species. Numerical approaches have not been utilized for taxonomic purposes among other taxa of the Malvaceae even though there seems to be ample scope for an examination of the applicability of these techniques to an assessment of the taxonomic relatedness of the taxa belonging to this family. The present investigation was, therefore, undertaken to determine the taxonomic relationship by using numerical analyses of 12 taxa at intraspecific and infraspecific levels. Department of Botany, Jahangirnagar University, Savar, Dhaka-1342, Bangladesh. Bangladesh Jute Research Institute, Shere-e-Bangla Nagar, Dhaka, Bangladesh.


Introduction
The genus Hibiscus Medik. of family Malvaceae exhibits considerable taxonomic complexity. In Bangladesh, Hibiscus cannabinus L. (Deccan hemp or Kenaf) and H. sabdariffa L. (Rosella or Mesta), are cultivated and H. acetosella L. and H. radiatus L. are wild. In recent years H. cannabinus and H. sabdariffa are getting much attention and grown commercially for paper-pulp production in many countries (Andrew andPiters 1980, Nieschlag et al. 1960). In Bangladesh, paper and pulp mills have recently introduced Kenaf (H. cannabinus) along with jute whole stem as raw materials for paper and pulp making (Anonymous 1993). This new use has led to investigate about the component characters contributing to biomass production of the above four species. The fibre of jute (Corchorus capsularis and C. olitorius), Kenaf (H. cannabinus) and Mesta (H. sabdariffa) are considered as economic yield for textile purpose, while air dry whole stem is considered as biomass in paper-pulp industries (Kalder 1991).
Despite the high socio-economic significance no major breakthrough has been achieved in research relating to these above species. Numerical approaches have not been utilized for taxonomic purposes among other taxa of the Malvaceae even though there seems to be ample scope for an examination of the applicability of these techniques to an assessment of the taxonomic relatedness of the taxa belonging to this family. The present investigation was, therefore, undertaken to determine the taxonomic relationship by using numerical analyses of 12 taxa at intraspecific and infraspecific levels.

Materials and Methods
Three cultivars of Hibiscus cannabinus viz., HC-95, HC-2 and CP1 72126/1; four of H. sabdariffa viz., var. HS 24, breeding line 300M, cultivar 2065 and cultivar Samu 93; three forms of H. acetosella viz., Green Foliage Yellow Flower (GFYF), Green Foliage Magenta Flower (GFMF) and acc. Red Foliage Crimson red flower (RFCRF) and two forms of H. radiatus viz., Tall with magenta flower and Dwarf with yellow flower were taken. The experiment was conducted at central station of BJRI, Dhaka. The experiment was laid out in a randomized complete block design (RBD) with three replications in each case. Recommended doses of fertilizers, irrigation, weeding, mulching and other cultural practices were performed as and when required.
Hierarchical cluster analysis for qualitative characters was performed following Binary Euclidian distance and Dendrogram was drawn using average linkage (between groups). Among the various morphological features qualitative characters of plant were used in cluster analysis and constructing dendrograms. Sixty-eight morphological characters were selected without any prejudices for each variety ( Table 1). The similarity coefficients of different OTU's were measured according to Sørensens (1948) and Sneath and Sokal (1973). The coefficients were clustered by UPGMA method as outlined by Sneath and Sokal (1973). All the analyses were computed using the software SPSS 10.0.1 standard version (Statistical Package for Social Sciences) released in 1999. The program was run through Windows 98 operating system, in a Pentium III model computer.

Results and Discussion
Based on 68 qualitative characters (Table 1), the similarity coefficients for each pair OTU's (operational taxonomic units) were calculated separately according to both Sørensens (1948) and Sneath and Sokal (1973) similarity measure and the data matrices were prepared. Based on these matrices dendrograms were constructed.
In both similarity matrices prepared from the values of the taxa examined showed that a few of the taxa have similarity coefficient greater than 0.50 with respect to the other taxa. The Sørensens's similarity coefficients varied between 0.211 and 0.919 while the Sneath and Sokal similarity coefficients ranged between 0.142 and 0.890 ( While the minimum coefficient value was observed between form RFCRF of H. acetosella and breeding line 300M of H. sabdariffa. However, some of the intervarietal similarity coefficients were found between 0.501 and 0.582, but maximum of them ranged between 0.135 and 0.481. At the intervarietal level, similarity coefficients value greater than 0.50 recorded in comparisons involving cult.  In all the three approaches of clustering (namely Sørensen's and Sneath and Sokal ), var. HS 24 of H. sabdariffa grouped with the cluster formed by the rest at distance greater than 20 and later joined with the cluster formed by cult. 2065 of H. sabdariffa and form RFCRF of H. acetosella at distance 25 ( Fig. 1 and 2). Pasha and Sen (1986, 1995, 1997 also worked on several taxa of Cucurbitaceae. In numerical analysis they have constructed dendrograms on the basis of Jaccards (1908) and Sørensen's (1948) similarity coefficient of 143 characters. The similarity coefficient of the 22 taxa varied between 0.36 and 0.91 indicated different levels of diversity among those species.