Opportunities to reduce the potential for disease infection and spread with strawberry plug plants

Strawberry plug, or tray, plants offer growers a means to minimize disease problems in transplants. This advantage has been widely recognized since development of the technology into a commercially feasible practice. There are, however, occasions during establishment of plug plants that may predispose them to some diseases that otherwise may not be of consequence in the field. In addition, some diseases caused by systemic pathogens, for example certain phytoplasmas (such as those associated with strawberry multiplier, green petal, and phyllody diseases) and bacteria (such as Xanthomonas fragariae) may be carried in symptomless runner-tip plantlets. Other diseases (such as anthracnose, caused by Colletotrichum species) may be carried with runner-tip plantlets in infections of stolons. These aspects of potential pathogens and occurrence of diseases in plug plants, as well as the roles of meristem culture of mother plants, soil-less culture media, vector control, and methods of strawberry plug-plant production that contribute to disease initiation and prevention will be discussed.