Abstract:
Curcuma L., a perennial rhizomatous herb, is gaining global importance as a source
of starch besides its medicinal property and use as a spice. Characterization of
germplasm is very essential in crop plants and it is the basis for selection of
accessions for use in crop improvement programmes. This research work was an
attempt to characterize the fifteen selected accessions in eight species of Curcuma
collected from different parts of India and maintained in the field gene bank of
ICAR-CTCRI using morphological and molecular markers. Two accessions in each
of C. amada, C. angustifolia, C. aromatica, C. decipiens, C. malabarica, C.
raktakanta, C. zedoaria and one of C. longa were selected. These 15 accessions
were morphologically characterized using 13 qualitative and 15 quantitative traits
and a wide variability was observed. Dendrogram based on the morphological
characters grouped the genotypes into four clusters. PCC analysis revealed that the
accessions of the same species have shown more than 83% similarity except C.
angustifolia. C. raktakanta accessions have shown a highest intra-specific
similarity of 94%. C. decipiens accessions were found to be the highly variable
from the most commonly exploited species C. longa while C. aromatica has shown
highest similarity. PCA showed that the characters such as leaf midrib colour,
rhizome flesh colour, leaf texture and aroma of rhizome have contributed mostly to
the variability. Molecular characterization was done using 10 ISSR and 7 SSR
markers. The total percentage polymorphism obtained by ISSR characterization
was 94.31 while it was 91.11 percentage in the SSRs. C. angustifolia-1 was found
to be highly variable from C. angustifolia-2 suggested the occurrence of intraspecific
variability. The intra-specific similarity among C. raktakanta accessions
were found to be highest than all other accession pairs. Clustering based on ISSR
markers grouped the genotypes into five clusters while SSRs into six clusters.
Mantel’s test showed a positive correlation between the morphological and
molecular data. The results of the present study indicated that the morphological as
well as the molecular tools were found to be very effective in the characterization
of germplasm of Curcuma species for the developement of core collections and for
further use in the crop improvement programmes.
