Induction and evaluation of colchitetraploids of two species of Tinospora Miers, 1851

Abstract

Autotetraploidy, both natural and/or induced, has potential for genetic improvement of various crop species including that of medicinal importance. Tinospora cordifolia (Willdenow, 1806) Miers, 1851 ex Hooker et Thomson, 1855 and T. sinensis (Loureiro, 1790) Merrill, 1934 are two diploid species, which are dioecious, deciduous and climbing shrubs with high medicinal importance. Among the three methods used for induction of polyploidy by colchicine treatment, it was cotton swab method which successfully induced the polyploidy in both species. The morphological and cytogenetical features of the synthetic tetraploids were compared with their diploid counterparts. The tetraploids were morphologically distinct from diploid plants. They exhibited larger organs, such as stem, leaves, inflorescence, fruits, flowers and seeds. The tetraploids were characterized by the presence of low quadrivalent frequency and high bivalent average. Unequal distribution of chromosomes at anaphase I was found in 60% cells. The present study provides important information on the superiority of autotetraploids as compared to diploid counterparts in both species.

Genetic variability, heritability, correlation and path analysis in seenthil kodi (Tinospora cordifolia)

“…The average petiole length of T. cordifolia genotype collected from the northwest Himalayan region of India has been reported to be 7.61 cm with a range of 5.15 cm to 10.37 cm (Rana,2012) . Thakur et al (2020) observed that the Tinospora species had a leaf length of 4.81 cm, leaf width of 5.67 cm, and petiole length of 4.28 cm. Similarly, Abhijeet and Mokat (2018) reported in vegetatively propagated Tinospora species using stem cuttings, the petiole length was 3.71 cm, leaf length was 4.49 cm, and leaf width was 3.97 cm.…”