Redifferentiation and Dedifferentiation.

Intellectual property right (IPR) is a category of property that includes intangible creation of the human intellect, and primarily consists of copyrights, patents, and trademarks.

Cryoprotectants are the protective agents that are used to protect the cells or tissues from the stress of freezing temperature. E.g: Sucrose.

The morphological changes occur in the callus leading to the formation of shoot and roots is called organogenesis.

Based on the explants some other plant tissue culture types are:
1. Organ culture
2. Meristem culture
3. Protoplast culture
4. Cell culture

(a) Callus is a mass of unorganized growth of plant cells or tissues in in vitro culture medium.
(b) The callus cells undergoes differentiation and produces somatic embryos, known as Embryoids.

Glycine 2.0 mg/l, Nicotinic acid 0.5 mg/l, Pyridoxin HCI 0.5 mg/l and Thiamine HCI 0.1 mg/l.

1. Culture media are sterilized by Autoclaving.
2. Explants are surface sterilized by chemicals.

Sterilization is the technique employed to get rid of microbes such as bacteria and fungi in the culture medium, vessels and explants.

Basic concepts of plant tissue culture are totipotency, differentiation, dedifferentiation and redifferentiation.

Growing plant protoplasts, cells, tissues or organs away from their natural or normal environment, under artificial condition, is known as Tissue Culture.

Name of the process-Plant tissue culture Types:
(a) Organ culture
(b) Meristem culture
(c) Protoplast culture
(d) Cell culture

Somatic embryogenesis is the formation of embryos from the callus tissue directly and these embryos are called Embryoids or from the in vitro cells directly form pre-embryonic cells which differentiate into embryoids
Applications:
i. Somatic embryogenesis provides potential plantlets which after hardening period can establish into plants.
ii. Somatic embryoids can be used for the production of synthetic seeds.
iii. Somatic embryogenesis is now reported in many plants such as Allium sativum, Hordeum vulgare, Oryza sativa, Zea mays and this is possible in any plant.

1. The growing of cells including the culture of single cells or small aggregates of cells in vitro in liquid medium is known as cell suspension culture.
2. The cell suspension is prepared by transferring a portion of callus to the liquid medium and agitated using rotary shaker instrument.
3. The cells are separated from the callus tissue and used for cell suspension culture.

Sterilization of Nutrient Media:
1. Culture media are dispensed in glass containers, plugged with non-absorbent cotton or sealed with plastic closures and then sterilized using autoclave at 15 psi (121^o(C)  for 15 to 30 minutes.
2. The plant extracts, vitamins, amino acids and hormones are sterilized by passing through Millipore filter with 0.2 mm pore diameter.
3. Then added to sterilized culture medium inside Laminar Airflow Chamber under sterile condition.
Other techniques used to remove the microbes
(a) Maintenance of aseptic environment
(b) Sterilization of culture room
(c) Sterilization of explants