Submitted to: HortTechnology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 21, 1998
Publication Date: N/A
Interpretive Summary: Contamination with bacteria and fungi is a serious problem in the commercial production of plants by tissue culture. Antibiotics and fungicides are sometimes added but are not always effective, and have some drawbacks such as altering plant growth, the expense, and resistant microbial strains can result from continued use. We have tested Plant Preservative Mixture (PPM) in various types of citrus tissue cultures. PPM contains chemicals that are widely utilized as industrial preservatives (e.g. in paint, water cooling systems, swimming pools and spas, food and feed, metalworking fluids, paperpulp processes, cosmetics, soaps, detergents, fabric, and petroleum products). Our results indicate that PPM can be routinely added to tissue culture medium to inhibit the growth of bacterial and fungal contaminants without harming the plant tissue.
Technical Abstract: Controlling bacterial and fungal contamination in plant tissue cultures is a serious problem. Antibiotics are currently used but are not always effective, can alter plant growth, are costly, and resistant strains can result with extensive use. Plant Preservative Mixture (PPM) contains a mixture of isothiazolones which are a class of broad-spectrum, widely utilized, industrial biocides. The isothiazolones used in PPM are reported by the manufacturer to be nonphytotoxic and suitable for the prophylactic control of microbial contaminants in plant tissue cultures. Our results indicate that PPM can be routinely added to tissue culture medium for the effective control of bacterial and fungal contaminants present at low inoculum densities.