robust plants, leading to accelerated growth compared to similar plants produced by conventional methods - like seeds or cuttings. Some plants with very small seeds, including most orchids, are most reliably grown from seed in sterile culture. A greater number of plants can be produced per square meter and the propagules can be stored longer and in a smaller area. Disadvantages Micropropagation is not always the perfect means of multiplying plants. Conditions that limits its use include: Labour may make up 50–69% of operating costs. A monoculture is produced after micropropagation, leading to a lack of overall disease resilience, as all progeny plants may be vulnerable to the same infections. An infected plant sample can produce infected progeny. This is uncommon as the stock plants are carefully screened and vetted to prevent culturing plants infected with virus or fungus. Not all plants can be successfully tissue cultured, often because the proper medium for growth is not known or the plants produce secondary metabolic chemicals that stunt or kill the explant. Sometimes plants or cultivars do not come true to type after being tissue cultured. This is often dependent on the type of explant material utilized during the initiation phase or the result of the age of the cell or propagule line. Some plants are very difficult to disinfect of fungal organisms. The major limitation in the use of micropropagation for many plants is the cost of production; for many plants the use of seeds, which are normally disease free and produced in good numbers, readily produce plants (see orthodox seed) in good numbers at a lower cost. For this reason, many plant breeders do not utilize micropropagation because the cost is prohibitive. Other breeders use it to produce stock plants that are then used for seed multiplication. Mechanisation of the process could reduce labour costs, but has proven difficult to achieve, despite active attempts to develop technological solutions. References Agronomy Horticulture Plant reproduction