Modernization in plant tissue cultu

Modernization in plant tissue culture techniques led to the augmentation of various cultures, which has provided a new platform for in vitro studies in the plant cell. On the basis of their morphology these cultures are subdivided into organized and unorganized cultures. Organized cultures contribute toward the creation or maintenance of defined structures whereas unorganized cultures usually aim toward growth of undifferentiated mass of cells called callus. Growth and development of such cultures are primarily dependent on the type and composition of supplemented nutritional medium. Depending upon the nature of explants and objective of in vitro studies there are different types of media that are available in the market. Compositional analysis of growth medium assists in the optimization and selection of the suitable medium for the desirable explants. Media and their preparation require a lot of precautionary measures (pH control, precipitation of salts, autoclaving of sucrose and synthetic hormones, etc.) to avoid contamination and other problems. Supplementation of single or multiple hormones plays an important role in directing the growth of callus. Induction, subculturing, and maintenance of callus require suitable protocols for their significant growth and development. Furthermore, the growth efficiency of callus can be assessed by studying various parameters during in vitro studies. This chapter gives an exhaustive knowledge of the type of cultures, media, and studies that are involved in the growth and development of callus.