Indian Journal of Science and Technology

Abstract

A desynaptic mutant of Corchorus fascicularis Lamk. (Family: Tiliaceae) showing distinctive morphological variations than normal was identified from the natural population (1 out of 27 plants scored) of jute species following male meiotic analysis. Self segregation of the desynaptic plant suggested that desynapsis (mutant trait) was monogenic recessive to normal. Compared to normal plants, the spontaneous desynaptic mutant (medium strong type) demonstrated enhanced univalent frequency per cell (4.05, normal-0.31), reduced number of chiasma (6.67, normal- 7.28) and bivalent (5.12, normal- 6.99) per nucleus, few meiocytes (13.64%, normal-5.36%) with unequal separation at AI, cytologically near normal AII (94.83%, normal- 100.00%) cells and high male fertility (81.77%, normal- 92.06%). Cytomixis (prophase I/ metaphase I) was evident in both normal and mutant plants forming aneuploid (mutant: 2n< 14-1.40%, 2n> 14-2.80%; normal: 2n<14 - 14.20%, 2n>14 - 10.22%) PMCs predominantly at MI (mutant: 4.20%, normal: 24.42%) and rarely in AI (mutant: 1.52%, normal: 1.79%) cells.

Keywords: Corchorus fascicularis, desynapsis, medium strong type, monogenic recessive, morphological variations, cytomixis, aneuploidy, high male fertility