Cyto-morphological and Biochemical Studies of Pointed Gourd (Trichosanthes dioica Roxb.

Abstract

This investigation was conducted to study the morphological, cytological and biochemical behaviours among eighteen varieties/lines of Trichosanthes dioica (Roxb.). Morphological variations in eighteen varieties/lines of Trichosanthes dioica were determined by Metroglyph method which might have reflected their genetic relationship. Interphase nuclear phenotype of Trichosanthes dioica were studied in present investigation. Interphase nuclear volume (ICV) was measured. Percentage heterochromatin values were also calculated statistically by determining the area of nucleus and of chromocentres by planimetry. Then the heterochromatin values were expressed as percent nuclear area. Lengths and ratios of representative complement of shoot tip chromosomes of Trichosanthes dioica were determined at the desirable stage of cells and were plotted in scatter diagrams. The average values of total length and arm ratio were calculated constituting the haploid complement of those cells. Then the chromosome of haploid complements were numbered in decreasing order of total chromatin length and increasing order of arm ratio within the same length. Total frequency was estimated and the values were expressed in percentage. Finally, the standard karyotype was derived based on centromeric formula and range of chromatin lengths per chromosome. From extensive karyotypic analysis in the present study sex chromosomes were identified based on probabilistic inferences. The sex chromosomes were assumed completely based on inferential way and they were termed as sex regulatory. They varied from variety to variety/line and thus, it was also assumed that the sex in pointed gourd is governed by the particular gene. Preliminary phytochemical analysis of metabolic extracts from leaves of pointed gourd (Trichosanthes dioica Roxb.) revealed the presence of alkaloids, flavonoids, glycosides, tannins and steroids in different density. Quantitatively two phytochemical compound i.e., soluble sugar and chlorophyll content were estimated from the extracts of leaves. Estimation of protein, phenol, proline and antioxidant capacity (%) were made from the extracts of fresh fruit of pointed gourd. The antioxidant capacities of methanolic fruit extracts of Trichosanthes dioica was determined by in vitro assay models such as DPPH free radical assay. Polyacrylamide gel electrophoresis was used for determining protein banding pattern in ten varieties/lines of T. dioica. Variations were observed in number and intensity of bands. A total of 47 bands were found and highest similarity was found to be 80% between BARI 1 and BARI 2. Lowest index was found to be 14.28% between BARI 1 and PG006 of pointed gourd.