Abstract
Micropropagated plantlets of four citrus species, viz., Citrus reticulata Blanco, C. volkameriana, C. reshni, and C. nobilis x C. deliciosa were simultaneously rooted and acclimatized in culture jars filled with soilrite or soilrite topped over farmyard manure (FYM). The protocol involved direct planting of 6- to 8-week-old in-vitro-proliferated microshoots (2-2.5 cm long) in sterile soilrite or soilrite topped over FYM. Root initiation in the various species ranged from 9 to 19 days in the different carriers. Shoots rooted in soilrite topped over FYM resulted in improved growth and better establishment after transfer to the soil. This single-step rooting and acclimatization of in-vitro-proliferated citrus microshoots is an improvement over rooting in agar medium. Better rooting (80-91%) and very high ex vitro survival (90-97%) was achieved using this protocol, hence, overcoming the problem of transplant shock, a major problem in the establishment of micropropagated plants of citrus.
