Brassinosteroids and their analogs: Feedback in plants under in vitro condition

Brassinosteroids (BRs) are the sixth important plant hormones that induce their effect at micro-level concentration. The importance of its analogous under in vitro condition for many studies includes the study of response in plants aimed at improving various developmental, physiological, morphological, biochemical processes without the involvement of climatic factors, nutrients and diseases. BR improves and increases regeneration and multiplication rate by induction of callus growth, somatic embryos, tracheary elements, shoot elongation, formation of 2embryogenic tissue, stimulation of branch elongation, etc. These provide rapid disease-free clonal propagation of improved varieties within less time and space. BRs improve photosynthetic processes, antioxidant enzymes activities, synthetic seed production and elicitation of secondary metabolites production. Most importantly, it provides resistance from abiotic stresses, for example, oxidative and salinity stress. This review summarizes role of brassinosteroid and its various analogs in improving different morphological, physiological and biochemical attributes in various crop plants grown in vitro, both under normal as well as abiotic stress conditions.