Vol. 11, Issue 12 (2022)

Author(s):
Eram Arzoo, Reeta Bhatia, Kavita Dubey, Kanwar Pal Singh and Sapna Panwar

Abstract:
African marigold (Tagetes erecta L.) belongs to the Asteraceae family and is originated at South and Central America, specifically from Mexico. Gynogenesis leads to rapid development of homozygous parental lines in the shortest possible time, which will further help in development of high-yielding F1 hybrids, but their hardening is still the hardest parts of their production. The high percentage of plant loss is obtained when multiplying and transferring to an ex vitro environment, however, frequently limits its wider use. Therefore, the objective has been made to develop efficient protocol for in vitro hardening of gynogenically induced regenerates in African marigold. Well-developed healthy gynogenically induced plantlets after in vitro multiplication and rooting of genotypes ‘DAMH-24’ and ‘DAMH-55’ used as explants. These plants were transferred to the different pots containing hardening media i.e. mixture soilrite, cocopeat and perlite in the ratio of 1:1:1 (v/v) with ¼ strength MS medium. Out of the different in vitro hardening techniques, plastic pots covered with polythene cover gave the best results; highest percent survival (70.0%), maximum number of leaves (9.17), highest shoot length (8.24 cm) as well as best visual growth scores (4.5). Among both genotypes ‘DAMH-24’ performs best towards in vitro hardening of gynogenically induced plantlets. This protocol is highly useful for development of plants after hardening of in vitro gynogenically developed plantlets.