• Agar: natural product extracted from algae

• Gelrite: a gellan gum (hetero-polysaccharide) produced by the bacterium Pseudomonas elodea

Different agar brands

Agar and gel characteristics

label and type

• impurities

• moisture content

• culture growth

concentration

• water potential

• hardness

• culture growth

• physiological problems: hyperhydricity

• cytokinins