Chitosan for Improving Orchid Production and Quality

Abstract

Chitosan is a deacetylated derivative of chitin that is derived from the cell walls of fungi, crustacean exoskeletons, cuticles of insects and some algae. It is considered environmental friendly for agricultural uses as it is easily degradable and non toxic to humans. Chitosan and its derivatives have been reported to elicit natural defence responses in plants and it has been used as a natural compound to control pre-and postharvest pathogenic diseases. Chitosan application has also been shown to increase yields of some agricultural crops. Chitosan has recently been reported to act as a plant growth promotor in some species including orchids. The degree of deacetylation and concentra-tions of chitosan have varying effects on the growth and development of orchid cultured in vitro. Spraying with chitosan has been shown to significantly reduce the severity of leaf spot disease in orchids. Also, it has been shown that application of chitosan to Dendrobium